Rotel RMB-1095 Specification inaccuracy

Collapse
This topic is closed.
X
X
 
  • Time
  • Show
Clear All
new posts
  • mitch57
    Senior Member
    • Nov 2004
    • 429

    Rotel RMB-1095 Specification inaccuracy

    Hi all,

    I'm a newbie to this forum but thought I would post one of my concerns to see what all of you had to say. I just purchased the RMB-1095 last week. Great sounding amp paired with my Def Techs and Denon 3805.

    However, I have one concern which Rotel doesn't seem to want to address. I am sure many of you are aware that the manual for the 1095 incorrectly states the "Power Consumption" as being 800 Watts instead of 1200 Watts. Initially I wasn't to concerned about this until I actually got the amp home and took it out of the box. Right there on the back of the amp etched in the "Power Consumption" block was the same error "Power Consumption" 800 Watts!

    Rotel acknowledges the error in the manual. They told me they have no plans to issue an addendum to the manual or post any updated information on the web site. I pointed this out to Tech support and told him the same thing. I said I wouldn't even question it if the amp itself had the correct information. But when both the amp and the manual say the same thing I became somewhat suspect. He said he emailed Rotel and is awaiting an answer. That was last Thursday. I haven't heard back yet. I emailed Rotel tech support so I assume he must have emailed the engineers.

    Here's my concern. Down the road when I upgrade my system and try to sell the amp claiming it's rated power is 200 Watts X 5 the potential buyer could question the fact that both the manual and the amp state it's "Power Consumption" is 800 Watts.

    How can an amp consume 800 Watts of power and out put 1000 Watts? Why would they not want to correct this problem? What does that say about their Quality Control practices?

    Has anyone else questioned Rotel on this issue?
    Mitch
    :stupidpc:
  • aarsoe
    Senior Member
    • May 2004
    • 795

    #2
    I am not saying the 800 watt is correct, but if it is, then there would be no way that the 1095 could deliver 5x200w.
    A class ab amplifier have at best a 60% effeciency, the rest is heat and other loss. This would mean that the total max power availeble would be 480 watt, or just about 95 watt pr channel.

    Now having said that - I dont buy it. I happen to own the 1095, and it is clearly more powerfull than that. Also the two torrodials alone can draw more current, and there have been so many tests of this unit without anyone ever measuring it below the specs.

    Now, I just hope that the 800 watts is not in iddle, as my elec. bill would kill me.. ;-)

    Comment

    • Kevin D
      Ultra Senior Member
      • Oct 2002
      • 4601

      #3
      Had to do a little searching, as it was expalined to me before. But here's how amps seem to disobey power laws (and can produce a lot more power that they consume). 800 watts consumption is probably right, and the amp can produce 1000watts of power, or more at lower ohm loads:

      The 1st law of thermodynamics states, "The amount of energy in a system always remains constant". The key word here is ENERGY. Do not confuse energy (Joules) and power (watts). The two are related but not identical. Energy = Power x Time. Thus. A device producing 1 watt of power, over 1 second of time will have produced one joule of energy.

      We can (greatly) simplify the amplifier input/output equation to: Energy In = Energy out, or (Power in x Time in) = (Power out x Time out). Yes I know I’m ignoring efficiency etc, but stick with me, I’m attempting to explain why the apparent output power can exceed input power. Where was I? Yes, It’s all got to do with TIME. If input time is LARGE (long), and output time small (short). Then output power MUST be greater than input power for the equation to balance. Which is exactly what happens with switch mode power supplies.

      The mains input has a relatively long duty cycle compared to the short “bursty” audio signal on the output. Thus the amplifier can obtain the same input energy with less electrical power (watts) than on the output. Confused? Maybe I should try a water pipe analogy? They always worked at Uni.

      Imagine a water storage tank feed by a pipe. The input pipe is thin and thus can only deliver a relatively small flow of water (input power). However given enough time this small flow will eventually fill the large tank. Once full, the large tank has very high potential energy, and thus can deliver a larger flow of water (output power) when the output valve is open. However it can only do this for a very short period of time. Then the output valve must be closed, and the thin input pipe must again slowly fill the tank. Obviously the tank cannot deliver more output water (energy) than was delivered via the input, but it can do it at a faster rate (higher power) for a short period.

      I trust this has helped clear up some of the mysteries surrounding amplifiers that apparently disobey the laws of physics.

      Comment

      • aarsoe
        Senior Member
        • May 2004
        • 795

        #4
        Kevin - that sounds like something companies would state when designing amp's with below par spec. Even though there is no real measuring standard, I still believe that the power when measured has to be given over a certain amoun of time - an amount that would drain the capacitors for all availeble energy.
        Now if only I could find that test of the 1095 with all the measurements then we would know for sure..

        Comment

        • aarsoe
          Senior Member
          • May 2004
          • 795

          #5
          Also - if you look at Rotels own specified specs, it clearly states , Continuous Power Output 5x200 watts /ch / 8 ohms

          PS: If you look at the rotel website (US version) it also states power consumption to be 1200 watts - now the confusion is total...

          Comment

          • Andrew Pratt
            Moderator Emeritus
            • Aug 2000
            • 16507

            #6
            Let me look into it. On both the European and North American websites it says 1200 watts but you're right the manual states otherwise.

            As for differences in consumption vs output I'd imagine that the capacitors play a very large role in any amps output potential more so then the current from the wall outlet.

            Comment

            • Stevebez
              Senior Member
              • Oct 2003
              • 458

              #7
              So off the website

              Max Cont Pwr Output 8 Ohms; Power Cons; Rough Rel Efficiency

              1075; 5x120; 800 Watts; 600/800 = 75%
              1095; 5x200; 1200 Watts; 1000/1200 = 83%
              1080; 2x200; 550 Watts; 400/550 = 73%

              This kinda makes sense to me.

              You cannot have CONTINUOUS power output greater (or even equal to) Gross Power Cons as no amp is 100% efficient.

              Only way to check is to put an amp meter on the power cord feeding the 1095 / 1075 at full tilt and we can settle this - sorry but I dont have a amp meter of the type that uses the field effect of the cable to do the reading.

              Makes you wonder about shielded cables - but I won't go there now ... one issue at a time!

              Using P = I x V

              P =Power (Watts)
              I = Amps
              v = volts (eur vs us)

              and we should be sorted.

              Rgds Steve
              Last edited by Stevebez; 09 November 2004, 10:49 Tuesday. Reason: editing / formatting

              Comment

              • mitch57
                Senior Member
                • Nov 2004
                • 429

                #8
                If you call tech support they will tell you that the manual was misprinted and that the actual Power Consumption is 1200 Watts. Which, by the way, is what the specification sheet reads on the website as pointed out by Andrew.

                What bothers me is that I can't seem to get a straight answer from Rotel on this issue. Maybe you guys can help me get this cleared up.

                Thanks in advance.

                Mitch
                Mitch
                :stupidpc:

                Comment

                • Bing Fung
                  Ultra Senior Member
                  • Aug 2000
                  • 6521

                  #9
                  In "Audio" Magazine (Audio Volume 84 Number 2) Feb-March 2000, the 1095 was reviewed by Edward J. Foster.

                  The lab tested graphs "THD + N (%) Vs Freq (Hz) @ 200 Watts - 8 ohm loads All Channels Driven". Shows All channels driven @ 200Watts 8 ohm, THD is no more than 0.03% 20 Hz-20 KHz. On average THD looks to be 0.005% until about 5 Khz, then it gently curves upward to the maximum of 0.03% at rated power.


                  Additionally another graph "THD + N (%) Vs Output (Watts) @ 20 Hz, 1 KHz, 20 KHz - 8 ohm loads" had this annotation

                  "Figure 4 shows THD +N versus output into 8 - 4 ohm loads at three test frequencies. 20Hz, 1KHz, & 20 KHz. The results are remarkable in several aspects For one thing , the curves reveal that the RMB 1095 can deliver essentially the same maximum output power independant of frequency, which is rare. All the curves in Fig4A head up to 250 watts and cross the 1% line at 285 watts"
                  The Graph looks to be all below 0.01% THD until about 250 watts, then spikes upwards.

                  Sorry I can't show the graphs as my scanner/PC is Borked :M Overall though it shows the 1095 met it's specified power requirements (all channels driven), and actually did it with plenty of head room.
                  Bing

                  Comment

                  • dermie999
                    Member
                    • Jul 2004
                    • 96

                    #10
                    Originally posted by Bing Fung
                    ....
                    Sorry I can't show the graphs as my scanner/PC is Borked :M Overall though it shows the 1095 met it's specified power requirements (all channels driven), and actually did it with plenty of head room.
                    The 1095 is a bloody good amp by the sounds of things (unfortunately I can only dream at this stage new - new front speakers are my current obsession). However Mitch57 is right that the printed documentation is incorrect (or appears to be when compared with their website specifications).

                    Rotel have a process for correcting errors in the printed documentation. When I got my RMB 1080 (sigh, its a wonderful addition to my Rotel family) the documentation came with an erratum sheet which corrected an error in the manual. Has me beat why they won't contemplate doing this for the 1095.

                    Having said that still I say Rotel make a great quality product and I wouldn't be without it.


                    Trevor

                    Comment

                    • chrispy35
                      Senior Member
                      • Feb 2004
                      • 198

                      #11
                      Does any of the electrical safety standards bodies (UL, CSA, CE...) check stated power consumption vs. actual power consumption as part of their certification process? If so, how did this error get through?

                      Comment

                      • DrBoom
                        Senior Member
                        • Dec 2003
                        • 325

                        #12
                        I don't know how they get to these numbers either, but I don't look too critical at power ratings on the back.
                        If it's anywhere near the rated output x channels, then it's OK.
                        It doesn't take a genius to figure out that a Sony (or other large brand) receiver with a 340W power consumption can't deliver 6x100W or whatever.
                        For example, my Parasound HCA2205AT is rated 5x220W at 8 ohms and 5x300W at 4 ohms, has a transformer of 2000VA and is said to consume 1500W (at the rear).
                        Actually you should look at the transformer size, it's a much better indication of what it can and can't supply.
                        They never state at which point the amp consumes the rated 1500W power, but the transformer can deliver 2000VA (which is like Watts but without multiplying it by cos phi).
                        The Rotel RMB1095 has 2x 1.25 KVA transformers, so a total of 2500VA is available, which is plenty to achieve its rated power output.

                        Comment

                        • Bing Fung
                          Ultra Senior Member
                          • Aug 2000
                          • 6521

                          #13
                          Originally posted by dermie999
                          The 1095 is a bloody good amp by the sounds of things
                          Yes, The review basicaly summed it up with...

                          "Effortless" is the word of choice. No matter what music I handed it, no matter what movie soundtrack, the RMB-1095 refused to cry uncle. In stereo in my music listening room, it held it's own against my reference Bryston 4B-ST so well that I could not tell them apart with any degree of surety, on any music, despite the Bryston's slightly higher power rating....

                          Thats high praise for the Rotel, because the Bryston is an excellent amplifier, Technically I attribute this performance to the RMB-1095's remarkable bandwidth, distorsion that is not only low but virtually independant of the power being drawn, the amp's ability to drive high currents into low impedence loads with out batting an eye, and it's low uniform output impedance. It is a most remarkable amplifier...

                          I would be most happy to install the Rotel RMB-1095 as a reference amp in my home theater. It's musical, it's powerful, and it got the most out of my speakers. From the test results, I dare say it will get the most out of your speakers, too, because it really doesn't seem to give a damn about what kind of load it's driving. It's that kind of amplifier - the best kind. I recommend it with enthusiasm.

                          I would tend to agree....
                          Bing

                          Comment

                          • mitch57
                            Senior Member
                            • Nov 2004
                            • 429

                            #14
                            I'm not disputing the fact this is a great amp. I have owned it for a little over a week now and so far I love it.

                            My issue is with labeling and documentation accuracy. It's obvious that the Rotel RMB-1095 out puts more then 800 Watts. But should I have to put it on the bench with all the test equipment in order to prove it just because all the documentation (including the unit itself) contradict the specifications?

                            How about ownership from Rotel? They verbally admit the errors but won't do it in writing! Utterly rediculous! Many big name manufactures make documentation errors but almost all of them issue addendums to correct those errors. A simple statement like the following is what Rotel should do:

                            "The Rotel RMB-1095 manual and the back of the amplifer incorrectly state the power consumption at 800 Watts. The correct power consumption rating should read 1200 Watts."

                            How hard would it be to put an addendum in PDF format on their website stating the correction? People could download it and/or print it and then put it in the their hard copy manual.

                            I have already printed the specification page from their web site which has the correct information but the downloadable PDF version lists all of their amps along with the incorrect specifications for the RMB-1095.

                            It's a gread amp at a great price! Come on Rotel! Take ownership for this great product and fix the mis-prints! Let your customers know that your on top of it instead of your customers letting you know that your not!
                            Mitch
                            :stupidpc:

                            Comment

                            • Bing Fung
                              Ultra Senior Member
                              • Aug 2000
                              • 6521

                              #15
                              I suppose, if it bothers you so much as to affect your enjoyment of the product :blink:
                              Bing

                              Comment

                              • mitch57
                                Senior Member
                                • Nov 2004
                                • 429

                                #16
                                Bing,

                                No it doesn't affect my enjoyment of the product. It's a "Pet Peeve" of mine. I am somewhat of a perfectionist and the little things like "attention to detail" tend to bother me.

                                I am also a computer tech/trainer and the lack of that attention to detail can have serious consequences in my business. Plus if Rotel were my company I wouldn't settle for mistakes to go uncorrected.

                                Don't get me wrong. I love the amp. I just spent 6 hours straight listening to it last Saturday night.
                                Mitch
                                :stupidpc:

                                Comment

                                • Bing Fung
                                  Ultra Senior Member
                                  • Aug 2000
                                  • 6521

                                  #17
                                  It's your life :wink: Enjoy as best as you can, Hopefully Rotel will make it right for you :T

                                  I suppose we all have things that make us clench, mine just tend to be more catistrophic :twisted:
                                  Bing

                                  Comment

                                  • Aussie Geoff
                                    Super Senior Member
                                    • Oct 2003
                                    • 1914

                                    #18
                                    Rotel are VERY slack at updating their web site

                                    Mitch57,

                                    Rotel are legendarily bad at updating their web site and manuals. For example they have been selling the version 3 and up of the RB-1080 which has dual WBT style binding posts supporting bi-wiring, for 12 months yet the manual and the web site PDF and back panel drawings still show the older model with single pairs of WBT binding posts.

                                    Equally the on-line manual for the RSP-1098 is still the original one and makes no mention of newer capabilities like Dolby Pro Logic IIx... (I suspect the printed one is still out of date as well)

                                    Often new products are for sale for months before they even appear on the web site!!!

                                    Marketing madness if you ask me - put in new features etc and don't spend $100 updating the web site to tell people!!!!

                                    Andrew – you may wish to “share” this with your Rotel friends who control the web site!!

                                    Geoff

                                    Comment

                                    • Andrew Pratt
                                      Moderator Emeritus
                                      • Aug 2000
                                      • 16507

                                      #19
                                      I'll pass our concerns along.

                                      Comment

                                      • mitch57
                                        Senior Member
                                        • Nov 2004
                                        • 429

                                        #20
                                        Geoff,

                                        I sure would like to go back to Perth for a visit. My ship visited Perth during my Navy career back in the late 70s. Great place with great people.

                                        Anyway, as far as the RMB-1095 is concerned were not talking about months here were talking about years!!! I think the RMB-1095 came out in 2000. Another 1 1/2 months and it will be 2005! Rotel tech support told me last week that they haven't made the RMB-1095 for quite some time. They are just selling the current stock they have on hand.

                                        Tech support also told me that Rotel doesn't keep them informed about much of anything. Why is that? The first time I questioned them about the RMB-1095 before I bought the amp the tech didn't know why the spec said 800 Watts! He had to ask someone else!

                                        Seems pretty odd to me. Rotel doesn't have that many products to keep track of! Good thing they're not auto mechanics! They would never be able to keep track of all those engines and transmissions!
                                        Mitch
                                        :stupidpc:

                                        Comment

                                        • mitch57
                                          Senior Member
                                          • Nov 2004
                                          • 429

                                          #21
                                          Originally posted by Andrew Pratt
                                          Let me look into it. On both the European and North American websites it says 1200 watts but you're right the manual states otherwise.

                                          As for differences in consumption vs output I'd imagine that the capacitors play a very large role in any amps output potential more so then the current from the wall outlet.
                                          Andrew,

                                          Did you find out anything on this yet?
                                          Mitch
                                          :stupidpc:

                                          Comment

                                          • AndrewM
                                            Senior Member
                                            • Oct 2000
                                            • 446

                                            #22
                                            Difference between a speaker getting 100w and 200w = 3db

                                            Comment

                                            • Andrew Pratt
                                              Moderator Emeritus
                                              • Aug 2000
                                              • 16507

                                              #23
                                              Andrew,

                                              Did you find out anything on this yet?
                                              No my contact is likely traveling again as I haven't heard from him lately.

                                              Comment

                                              • mitch57
                                                Senior Member
                                                • Nov 2004
                                                • 429

                                                #24
                                                Okay! I now have the answer to all my questions concerning the Power Consumption issue. Here is the email trail between Rotel and myself concerning power consumption on the RMB-1095.

                                                Sorry for not doing any editing prior to posting this email trail but I thought it was important to let everyone know the whole story. Remember to read from the bottom of this post first so you can read how it all started.
                                                -----------------------------------------------------------------------------------------------------------------------------------

                                                We have all been involved in this. It is something that has just never came up before so we were scratching our heads a bit too. Once we got answers from Rotel engineers then it all started to make sense.

                                                Best Regards,
                                                Shane Kea
                                                Technical Support
                                                B&W/Rotel
                                                ----- Original Message -----
                                                From: mwayman@att.net
                                                To: Shane Kea
                                                Sent: Friday, November 12, 2004 4:13 PM
                                                Subject: Re: RMB-1095


                                                Shane,



                                                Thanks for your patience in getting this matter cleared up for me. It's been rather confusing as I have gotten some conflicting information regarding this issue. I called one of the techs at the Rotel number listed on the web site and they told me the power consumption should have read 1200 Watts and not 800 Watts.



                                                Perhaps you could inform the rest of Rotel's Techs about this in case another customer calls and asks the same questions I did.



                                                Thanks again for your patience and diligence in this matter.

                                                -------------- Original message from "Shane Kea" <Skea@equityaudio.com>: --------------


                                                The website specifications were posted from the first preliminary specs that we got and then were not changed. I have spoken with the girl in charge of the website and we are working on getting that updated.
                                                The specifications that are in the owners manual and on the back panel are the final specs from Rotel engineers.

                                                Best Regards,
                                                Shane Kea
                                                Technical Support
                                                B&W/Rotel
                                                ----- Original Message -----
                                                From: mwayman@att.net
                                                To: Shane Kea
                                                Sent: Friday, November 12, 2004 10:14 AM
                                                Subject: Re: RMB-1095


                                                Shane,



                                                Thanks for the response. That brings up another question. If the manual and the back of the unit both indicate average power consumption, why does the RMB-1095's specification sheet on Rotel's website list the Power Consumption as 1200 Watts? See the link below for quick reference.



                                                Producing a full kilowatt (1000 watts!) of output power, Rotel's RMB-1095 is a stunning realization of Rotel's capabilities in amplifier design.




                                                I'm not trying to be difficult, I just want to be clear on the specifications.



                                                Thanks in advance for your patience.


                                                -------------- Original message from "Shane Kea" <Skea@equityaudio.com>: --------------


                                                I got the response back today. The power consumption figure that is stated on the back panel and in the owners manual is an "average" power consumption. It is not stated as the max power consumption due to the fact that there should not be a scenario where you are actually driving all 5 channels at full power. The power consumption varies with output power, so the test is carried out at a lower figure using "pink noise" to get an average.

                                                Best Regards,
                                                Shane Kea
                                                Technical Support
                                                B&W/Rotel
                                                ----- Original Message -----
                                                From: Mitch Wayman
                                                To: Shane Kea
                                                Sent: Wednesday, November 10, 2004 10:28 PM
                                                Subject: Re: RMB-1095


                                                Hi Shane,

                                                It's been about a week now. Have you heard anything from Rotel on this yet?
                                                ----- Original Message -----
                                                From: Shane Kea
                                                To: mwayman@att.net
                                                Sent: Thursday, November 04, 2004 5:49 AM
                                                Subject: Re: RMB-1095


                                                I have emailed Rotel and am awaiting an answer. I will let you know what their response is as soon as I get it.

                                                Best Regards,
                                                Shane Kea
                                                Technical Support
                                                B&W/Rotel
                                                ----- Original Message -----
                                                From: mwayman@att.net
                                                To: Shane Kea
                                                Sent: Wednesday, November 03, 2004 5:28 PM
                                                Subject: Re: RMB-1095


                                                I understand the manual being a misprint but what about the back of the unit itself? The physical unit has 800W etched in the Power Consumption block on the back.



                                                Where does common sense come into the picture? The manual and the back of the unit itself say the power consumption is 800W. Without the website information everything indicates 800W not 1200W.



                                                As a technician, I would rely on what's etched on the back of the unit and assume the manual was a misprint. But in the RMB-1095's case both the unit and the manual are incorrect.



                                                Somewhere down the road when I sell this unit the information won't be readily available on your web site and I will have to rely on the printed manual and the physical unit for documentation which are both incorrect. If I were the buyer I would question why I (the seller) was claiming 200W x 5 when the power consumption rating in the manual and on the unit state 800W total.



                                                I know it's power consumption is 1200W but I have no documentation to prove it. And from what your telling me Rotel doesn't either. If the unit had the correct information etched into the back I wouldn't even question it.



                                                Do you see my point?


                                                -------------- Original message from "Shane Kea" <Skea@equityaudio.com>: --------------


                                                The power rating in the back of the manual was a misprint. An addendum was never printed since it was usually common sense that the power consumption was greater than this. I do not know why other manufacturers go down to 5Hz but the specification for this amp was done to 15Hz. I was never given a reason as to why the specifications were done down to only 15Hz though.

                                                Best Regards,
                                                Shane Kea
                                                Technical Support
                                                B&W/Rotel
                                                ----- Original Message -----
                                                From: Mitch Wayman
                                                To: techsupport@rotel.com
                                                Sent: Sunday, October 31, 2004 8:32 PM
                                                Subject: RMB-1095


                                                Hi,

                                                I just purchased the RMB-1095. Why does the back of my unit and the manual list the power consumption as being 800W? It should be a minimum of 1000W. Am I missing something here?

                                                Also, I am curious as to why Rotel amplifiers have a frequency response that only goes down to 15Hz? I see most other amplifier manufactures go down to 5Hz.

                                                Thanks,

                                                Mitch Wayman
                                                Mitch
                                                :stupidpc:

                                                Comment

                                                • Andrew Pratt
                                                  Moderator Emeritus
                                                  • Aug 2000
                                                  • 16507

                                                  #25
                                                  Good to see you got it cleared up. I asked my contact and he promised that they were looking into it so I guess he'd already talked to Shane

                                                  Comment

                                                  • mitch57
                                                    Senior Member
                                                    • Nov 2004
                                                    • 429

                                                    #26
                                                    Andrew,

                                                    Hopefully we will see an update on the web site in the near future.

                                                    On another note... I will be posting pictures of my system on your site within the next week. Possibly even tomorrow. My system pales in comparrison to most of the other posts but it still ROCKS!

                                                    Let us know if you hear anything different from Rotel.
                                                    Mitch
                                                    :stupidpc:

                                                    Comment

                                                    • Wolfenstein 2k2
                                                      Member
                                                      • Jun 2004
                                                      • 86

                                                      #27
                                                      I don´t assume that Rotel will update their manuals, websites or brochures too soon Just have a look at the latest Rotel brochure available here in Germany. Both the 1095 and the 1090 are (still) accounted as "800 watts power consumption" amps. Hmm, concerning the 1090 this could be true as it is "only" a two-channel amp, or what do you think? However, we all know that the 1090 can deliver more than 1000 watts/ch at a 1 ohm load and it is also equipped with two 1,2VA transformers which can be compared to those used in the 1095. Thus, in my view I strongly believe that both amps are without doubt able to deliver at least the wattage they are accounted for (actually more than that). Many review magazines throughout the world confirm this. In the end, I would consider the "max power consumtion" to be of secondary importance - and Rotel certainly did not put two 1,2VA transformers into the amps just for fun :T Another example: A German review magazine recenty tested my 1075 and measured 5x 255 watts @ 4 ohm load. Having in mind that the 1075 has a 1,5VA transformer this sounds plausible to me (although "800 watts power consumption" is labeled on the back of the amp).

                                                      PS: Does anybody know why the 1095 is much heavier than the 1090? Does the 1090 also have a power consumption of 800 watts or 1200 watts?


                                                      Attached Files

                                                      Comment

                                                      • DrBoom
                                                        Senior Member
                                                        • Dec 2003
                                                        • 325

                                                        #28
                                                        The RMB1095 is built around 2x 1.2 KVA transformers, the RB1090 has slightly larger 2x 1.25 KVA transformers according to the Rotel site.
                                                        Power consumption at idle (amp on, no music playing) is 190W for the RMB1095 and 120W for the RB1090 which seems logical since the latter only has 2 channels.
                                                        Maximum power consumption should be around 2400W for both, but that would be really pushing everything it's got into a very very heavy load all channels driven at the same time.
                                                        Which is not a very likely situation
                                                        I think if you manage to draw 500W at any time you're pushing it quite good already
                                                        If you assume the 120W idle for the 1090, and let's say the amp is about 60% efficient which is a very plausible number for a class AB amp, if you were to pull 500W from the mains that would mean you were running 114W into each of its 2 channels.
                                                        500W - 120W idle power (transistor bias current etc.), leaves 380W but it's only 60% efficient so it's putting out 228W at the outputs, divided by 2 gives 114W.
                                                        I'm not saying this is how it is, but that's the theory
                                                        So I wouldn't worry about whether it draws 800 or 1200W, because chances are you'll never even get close to those numbers.

                                                        Comment

                                                        • GosonFletchy
                                                          Senior Member
                                                          • May 2004
                                                          • 183

                                                          #29
                                                          Why does any of this actually matter? I don't see where the power consumption rating is a big deal since it is constantly changing as you play something. Listen to the amp and if you like the way it sounds then use it.

                                                          G.

                                                          :grab:

                                                          Comment

                                                          • Bing Fung
                                                            Ultra Senior Member
                                                            • Aug 2000
                                                            • 6521

                                                            #30
                                                            -------------- Original message from "Shane Kea" <Skea@equityaudio.com>: --------------

                                                            I got the response back today. The power consumption figure that is stated on the back panel and in the owners manual is an "average" power consumption. It is not stated as the max power consumption due to the fact that there should not be a scenario where you are actually driving all 5 channels at full power. The power consumption varies with output power, so the test is carried out at a lower figure using "pink noise" to get an average.

                                                            Best Regards,
                                                            Shane Kea
                                                            Technical Support
                                                            B&W/Rotel
                                                            I though the above might have answered Mitch's question... :huh:
                                                            Bing

                                                            Comment

                                                            • mitch57
                                                              Senior Member
                                                              • Nov 2004
                                                              • 429

                                                              #31
                                                              Bing,

                                                              It did answer my questions. The manuals and the back of the amp list the correct Power Consumption based on average power consumption not maximum power consumption.

                                                              The only discrepancy left to correct is the specification on the web site which reads 1200 Watts vice 800 Watts. Rotel also indicated that they were going to update the specification sheet on the web site.

                                                              I am satisfied with Rotels response and as far as I'm concerned I consider the case closed.
                                                              Mitch
                                                              :stupidpc:

                                                              Comment

                                                              • Bing Fung
                                                                Ultra Senior Member
                                                                • Aug 2000
                                                                • 6521

                                                                #32
                                                                Good to hear Mitch :T

                                                                Squeee-eeze 'em until you get your money's worth


                                                                Hey Wolf, your Amps are listing to the right :lol: Looks like they may be taking in water :rofl:
                                                                Bing

                                                                Comment

                                                                • Wolfenstein 2k2
                                                                  Member
                                                                  • Jun 2004
                                                                  • 86

                                                                  #33
                                                                  @ Bing

                                                                  Hehe, maybe I was just drunk while scanning the pages Do you still possess your B&W Series 600 speakers? I mean, the next logical step would be to upgrade them as they should be some kind of a bottle neck now. What about the Nautilus or the fabulous Matrix 800 series? We already talked about them some months ago in your "Please post pics of your Rotel equipment" thread.

                                                                  PS: In fact, the upper amps slant slightly to the right because this is a special German version - all transformers are mounted on the very right side of the chassis, and thus the amp is much heavier on the right side :W :rofl: :B

                                                                  Comment

                                                                  • Bing Fung
                                                                    Ultra Senior Member
                                                                    • Aug 2000
                                                                    • 6521

                                                                    #34
                                                                    Hey Wolf, Special Wolfsberg edition Amps :T


                                                                    The 600's do a good enough job for me now, given what they are. Sure a system can always sound better, however for now I'm fairly satisfied. I would like to upgrade the mains and centre, however it will be a substantial upgrade, so I'm in strategy planning right now. I would like to get a set of used CDNT 9's, or N803/4's for the mains, and then move my 603's to the LR surround, and the 601's for the Centre surrounds. What ever I get for the Mains will dictate the Center speaker.

                                                                    I'm also contemplating building a set of my own speakers, using the 7" Daytons and a Scan Speak 9800 tweeter in a MTM array, with 2 x 8" Dayton drivers below the MTM array. They would really rock. I just need Jon over in DIY to work out the drivers response and cross overs for me. Then I could start building if he gives them the green light. I would then work at building a full set of mains, centre & surrounds. Or I may build a full set of MTM M8As.. We'll see. I would also like to add a Rotel 1090 amp, or a Bryston 4B SST, however that will be after the speakers.

                                                                    So you see, I'm just enjoying my system now as I plan for the future, however as in life with limited budgets, priorities need to be instilled :evil:

                                                                    I just know I would eventually like speakers in the same ledgendary class as your Dynaudios :T
                                                                    Bing

                                                                    Comment

                                                                    • Wolfenstein 2k2
                                                                      Member
                                                                      • Jun 2004
                                                                      • 86

                                                                      #35
                                                                      I wouldn´t consider my Dynaudio Audience 52SE to be legendary :B However, they rock :T, especially with regard to its size and price! I like their neutral sound which is completely different to your and my former B&W speakers. Maybe you should primarily stick to B&W if you love their sound so much.

                                                                      One of my favourites are still the Dynaudio Special 25, but I cannot afford them at the moment. The next problem would be to find a matching center speaker as the Special 25´s design goes back to the old Dynaudio Contour series which is no longer produced. The current Contour or even Confidence series center doesn´t really fit optically (although I prefer the new modern design of both series). One could use another Special 25 as a center speaker, but I´am afraid that´s not an optimal solution (not magnetically shielded, no d´Appolito arrangement etc.). Maybe I should start listening to the Confidence series and forget the Special 25 But the prices are so damn... 8O Last but not least, I definitely would have to upgrade the power amps if I used either the Special 25 or Confidence series speakers - at home my RMB-1075 didn´t really manage to drive the Special 25´s in a way e.g. the NAD S-200 power amp could. Hence, a 1095, 1080 or even 1090 would be very preferable as Dynaudios always love power, power, power to run properly...

                                                                      Comment

                                                                      Working...
                                                                      Searching...Please wait.
                                                                      An unexpected error was returned: 'Your submission could not be processed because you have logged in since the previous page was loaded.

                                                                      Please push the back button and reload the previous window.'
                                                                      An unexpected error was returned: 'Your submission could not be processed because the token has expired.

                                                                      Please push the back button and reload the previous window.'
                                                                      An internal error has occurred and the module cannot be displayed.
                                                                      There are no results that meet this criteria.
                                                                      Search Result for "|||"