Will a 1075 make a difference?

[hery]

First of all I would like to thank all the members of this forum, especially Andrew for sharing their knowledge with us newbies and making us better informed to spend our hard earned cash wisely in some great gear and not be complacent with brands like Bose and so forth.

Thanks in part to this forum and others I learned about Rotel, B&W, SVS subs and so forth. I am the happy owner of a Rotel RSX-1055 with B&W CM 4 front speakers, CMC center, CM2 rears, SVS PB1-ISD sub with a Yamaha DV-C6480 DVD player and Mitsubishi 65711 TV.

I've been enjoying my gear now for close to a year now and couldn't be happier. And like everything else, you always want more of a good thing. So I ask: Will a 1075 amp make a difference in my 5.1 set-up and how should I hook it up? Thanks again for your invaluable help!!!

[soundhound]

I use the RSX-1055 and RMB-1075. I use the re-direct feature and use the internal amps for the rear center channels only (7.1 set-up). For the investment the RMB-1075 is a sizable improvement to the RSX-1055 internal amps. I run Klipsch RF3 series speakers and just recently picked up the RC-1070 for 2 channel for I personally wasn't satisfied with the RSX-1055's analog abilities. Butt, yes, the combo your'e thinking of will keep me satisfied for some time to come. Bob

[hery]

So soundhound if I understand correctly you only use the internal amps of the RSX-1055 for your 2 extra speakers in your 7.1 set-up. And in my case I'd be better off using only the 1075 for my 5.1 set-up? Thanks.

[Aussie Geoff]

Hery,

Your interpretion of what Soundhound is doing is correct - this is a very common strategy with Rotel buyers - start with a reciever and then add either or both a 5 ooe 2 channel amp to it, using the recievers amp for the rear channels (least critical). Allows the investment to be staged nicely..

Geoff

[soundhound]

sorry hery, in a nutshell the 1075 is much of an improvement. I listen to music and movies at possibly lower than normal levels and the 1075 to me still makes a noticable improvement in the sound, and besides the extra power reserve along with the extra flexibility it adds makes it well worth the price tag, Bob

[Andrew Pratt]

I've been enjoying my gear now for close to a year now and couldn't be happier.

Famous last words

Unfortunatly for your wallet yes adding the 1075 is going to be a significant improvement over the internal amps in the 1055 receiver. That's not to say those internal amps are decent but the reality is that any well built external power amp is going to have many advantages over internal amps on any receiver. Add to that the much larger and dedicated power supply and you will end up with great detail in your music, better bass response and over all more impact at all volume levels. It also opens up some interesting doors for the future like adding more speakers, going with seperates or adding a second zone etc.

[hery]

So the general consensus is that the 1075 will make me even happier than I am now, WOW, I only wish I could go for the gusto with a 1068 right now! That is my goal to eventually move into separates.
My dealer suggested that with the addition of a 1075, I should bi-amp my 5 speakers so I didn't waist the internal amps of the 1055, what do you guys think of that idea?
Again, thanks for sharing your experience with us!!

[aud19]

I wouldn't personally bi-amp with the 1075/1055. There's just too many diffferences in the components and signals. If anything bi-amp your mains with four channels from the 1075 and use the fifth to power the centre. Then power your surrounds with the 1055. This still also leaves you the option of going 7.1 or 2nd zone with your 1055 :T

Jason

[hery]

Thanks a lot for the great suggestions, keep them coming. Looks like I have my hands full with all these options you are giving me. :T Can't wait to pick up that bad boy, hopefully this weekend or next.

[ht_addict]

I wouldn't personally bi-amp with the 1075/1055. There's just too many diffferences in the components and signals. If anything bi-amp your mains with four channels from the 1075 and use the fifth to power the centre. Then power your surrounds with the 1055. This still also leaves you the option of going 7.1 or 2nd zone with your 1055 :T

Jason

This is what I did with my 1095 and now NAD S250/Pioneer 56TXi.. All it costs is the extra wire/2-RCA splitters and 2 extra interconnects. About $100 worth.

ht_addict

[Andrew Pratt]

If I was going to bi amp I'd use four channels from the 1075 to power the front two and the reamining channel on the centre...and use the 1055 to power the sides.

[hery]

Everybody seems to favor the idea of bi-amping the front two speakers, remaining channel for the center and the 1055 powering the 2 surrounds. Would I be sacrificing clarity and all those other great things you guys mentioned with this set-up in comparison to just connecting the 1075 to the 5 speakers? This is all a bit overwhelming or hard for a non-technical guy like me, can you guys explain in english the benefits. Thanks

[Taito]

Hi Hery. If you were to connect the 1075 to all five speakers and leave it at that, there would be an improvement, but you would be 'wasting' the amplification that you paid for in the 1055.

If you use the 1075 for the front channels only, you have five amplifiers for three channels. This gives you the option of biamping your front two channels - the part which confuses you if I am right.

If you bi-amp the front left and right, you will have one amplifier powering the bass and another powering the mid/treble on each of the front left and right. This means that the overall amplification for the front left and right channels isn't working as hard to achieve a desired volume. The amplifer powering the bass doesn't have to 'worry' about powering/controlling the mid/treble. The result is cleaner, better controlled and more authoritative bass. Similarly, the amp powering the mid/treble doesn't have to power the bass driver. This results in a cleaner, more detailed presentation of mids and highs.

The result is a 'better' sound from the front left and right speakers. To bi-amp your front left and right speakers, you will need a signal splitter for each of these channels so that you can send the front left signal to both front left amplifers and the front right signal to both front right amplifiers. (This is either a Y-style interconnect or a splitter block -takes the output from your receiver and turns it into two).

You can use your remaining 1075 amp to power the centre channel.

I'm not too sure about this part, but I think you can setup your receiver to use two of its amplifiers to power each of the two surrounds for the described benefits of biamping. There is a small bonus here also. As the 1055 is only using 4 out of its 5 power amplifers, the power supply will have more 'in reserve' for heavy transients (large dynamic swings in the music or move), resulting in a more effortless presentation.

If you choose this path, once you have set the gain levels on your channels accordingly, you SHOULD end up with a significantly better result than if you were to simply set up the 1075 as a single amplifer for each channel. As the front three speakers are all powered by identical amplifers, you will end up with a homoginous sound across the front three speakers, which will blend well into the less important surrounds.

NOTE: This has all been based on the assumption that your speakers can accept biwiring/biamping (they must have two pairs of terminals conected by two 'bridges' -at least your front L/R must, but your surrounds have to too if you want to bi-amp those with the internal poweramps of the 1055). When biwiring or bi-amping, you need to remove the bridge between the + and + terminal and the one between the - and - terminal of the speaker that you are bi-amping.

I hope this has been helpful, and cleared up rather than added to your confusion. If in doubt, speak to your dealer.

Good luck with whatever choice you make,
Ben

[hery]

Ben
That was an outstanding explanation of the advantage and procedure of bi-amping the front speakers with a 1075 and using the 1055 to amplifly the surrounds. And yes all my speakers can be bi-amped and are currently bi-wired with the bridges removed(B&W CM series). Only thing left now is to buy the 1075, y splitters and connectors. Hopefully within the next week or so. Thanks very much.

[Taito]

I'm glad it was helpful. That was far and away the longest post that I have ever made 8O . Let us know if you have any problems / what you think of your new setup when you get it up and running.

Cheers, Ben

[hery]

Ben
I will definitely let you guys know as soon as I buy my new toy and it's all up and running. The post was long but very well thaught out, didn't mind reading it at all and most likely will read it again to make sure I got it right. Appreciate the help, Salud.

[rotel_klipsch]

power and crossover needs

Below shows a chart of relative power distribution in typical passive crossovers. Since the bass is the most power hungry driver in your speaker, as the crossover point goes up the low end reguires more power and the more effiecient mid to high drivers less. If you were to use equal power amps (ie. 4 channels from 1075) you would want the crossover @350Hz. On my system the the crossover is @800 Hz so I use a rb1066 bridged to 150w to drive the bass and 2 channels from my 1075 (120W) to the upper driver (2-way speaker xover). In your case not knowing the xover point I would think the the 1075 could be used to drive the lower frequecies and the 1055 the upper and you would have less spl adjustments between lower and upper drivers..... OF COURSE, let your ears be your guides !!!!! ( I use an active xover and by-pass the passive xover and achieved unparralled results )

X-over Frequency (Hz) 250 Power to Bass 40(%) Mid+High 60(%)
X-over Frequency (Hz) 350 Power to Bass 50(%) Mid+High 50(%)
X-over Frequency (Hz) 500 Power to Bass 60(%) Mid+High 40 (%)
X-over Frequency (Hz) 1,200 Power to Bass 65(%) Mid+High 35(%)
X-over Frequency (Hz) 3,000 Power to Bass 85(%) Mid+High 15(%)
X-over Frequency (Hz) 5,000 Power to Bass 90 (%) Mid+High 10(%)

[hery]

Rotel Klipsch
You kind of blew me away with all those numbers and x-over points. Let me try this again, I think my dealer and you are suggesting the same thing:

Connecting the low frequencies of the 5 speakers (B&W CM4's, CMC and CM2's) to the 1075 and the high frequencies to the 1055.

Everybody else is suggesting that I bi-amp the front two CM4's with the 1075 and 5th channel for the CMC center and the 2 surrounds with the 1055.

What do you think would work better?

Thanks in advance.

P.S. I also have a sub hooked up: SVS PB1-ISD

[ajpoe]

This has been some very interesting reading. right now i am waisting 5 channels in my onkyo receiver and running my 5.1 system off my 1075. i have been looking at getting a 1080 for my fronts and running the rest of the system off the 1075 (hopefully do a 7.1 system in the future). If you guys had the option of getting a 1080 and not bi-amping anything, or bi-amping the fronts with 4 channels off the 1075, the extra channel for the center, and using the onkyo (over rated I'm sure at 100 watts/channel) to power the surrounds in my existing 5.1 setup... which would you choose? I have Paradigm Studio 60s v3 (always running full range) for my fronts so the 200 watts from a 1080 will be more than enough power. May be bi-amping with the 1075 would be too much? The 60s specs say suitable power is between 12-200 watts, but then also says a max input power of 150... I assume that is continuous. I know you're better with too much power vs. not enough, but when do you get to that point when that's not true anymore? I should note that I hope to get a 1068 some day which will eliminate those receiver channels, but I guess I'm asking for the time being.

ajpoe

[aud19]

You'll always be better off with one more powerful amp than bi-amping with a less powerful amp. Go for the 1080 Also just a note to Hery, you will not be able to bi-amp your L/R surrounds with the 1055. The redirect feature allows you to re-direct the main channels to the back centre surrounds for 7.1. It does not allow you to dedicate four channels to the L/R surrounds. Also for more info on bi-amping check out these threads:

http://www.htguide.com/forum/showthread.php4?t=8646&highlight=bi-amp

http://www.htguide.com/forum/showthread.php4?t=8294&highlight=bi-amp

Basically summing them up... "passive" bi-amping will give you some bennefit if you already have the extra channels but if you can, do a true bi-amp and you will gain much more bennefit from using more than one amp channel.

Jason

[Aussie Geoff]

Ajpoe,

I have been looking at getting a 1080 for my fronts and running the rest of the system off the 1075 (hopefully do a 7.1 system in the future). If you guys had the option of getting a 1080 and not bi-amping anything, or bi-amping the fronts with 4 channels off the 1075, the extra channel for the center, and using the onkyo (over rated I'm sure at 100 watts/channel) to power the surrounds in my existing 5.1 setup...

Personally I like your first option - the 1080 and the 1075 and letting the Onkyo channels "waste" - indeed - sell the Onkyo when you can and get a RSP-1068 (or even a second hand Rotel reciever if you really want to go down the bi-amping route). The reason for this is that I have never liked the sound of Onkyo HT reciever amplification (thin, hash/metailic and weedy spring to mind) and most testers find that the claimed 100W becomes something more like 40W a channel when all channels are driven.

If you want a reciever sell the Onkyo and by a second hand 1056 - then you can us its channels for the rears - they are a good tonal match for the rest of your system.

If all that is too much - get the 1075 on it's own and just use the Onkyo as a pre-pro for it... And again - get rid of it as soon as you can as it's pre-processor is a signficant step down from the Rotels for most people's ears (just ask HTguide member whmacs)!

I have helped several friends change over from Onkyo and they have all been amazed at the difference in musicallity and sound...

(Sorry - for the strong views but I needed to be honest about my views on this)

Geoff

[alkalay]

Hi Hery,

I know I'm a bit late on this one. I saw when you started up this thread but couldn't post.

I understand you kinda set your mind and soul on the 1068/1075.
I have recently accomplished that move and I have the 1075 driving CM4's, LCR60 S3 and a pair of 303.
The 1068/1075 and the CM4's in stereo sounds amazing, just wanted to tell you that. DD and DTS also sound great but as stereo is what I listen to most of the time I wanted to share my experience with the Rotel's, the CM4's and stereo listening.

Itai.

[soundhound]

Rotel - Klipsch had a very noteworthy point, He uses an active crossover, and I do understand there has been alot of controversy over that issue. If you were to truly bi-amp w/ the active crossover one could achive some incredible results using 4 of the 5 RMB-1075's channels, and let any recievers extra channels carry the sides and surrounds.

[aud19]

While you can use "any" reciever to power the remaining speakers I do recommend that you try to stick to Rotel for all of your amplification as you'll end up with more of a cohesive soundfield. Now using a 1075 for the fron three and your current receiver for a pre/pro and surroounds isn't a bad idea if you're on a tight budget and want to upgrade slowly.

Jason

[hery]

Aud19
Thanks for the recommendation, my current game plan is to eventually move into separates slowly, so I decided to add a 1075 with my 1055 receiver at the moment. As a matter of fact I went yesterday to my dealer to get one but they didn't have any in stock so they let me borrow a 1070 to get an idea of how my speakers would sound with 120 watts of power.
And gentlemen I have found out that a 1075 will make a difference, I connected the 1070 to the CM4's low frequency and the 1055 to the high's and listened to some CD's in 2 channel stereo and I was really impressed with what I heard. So monday my order goes in for a silver 1075 and yes, as per all the suggestions, I will definitely do a pseudo bi-amp connection to the fronts and remaining channel of the 1075 to the center, leaving me with 100 watts of power for my surrounds, can't wait!!
Thanks again for your assistance Aud19, soundhound, alkalay, Aussie Geoff, Rotel Klipsch, Taito and Andrew.