Sub - Best balance for music & HT

Collapse
This topic is closed.
X
X
 
  • Time
  • Show
Clear All
new posts
  • skvinson
    Junior Member
    • Dec 2002
    • 29

    Sub - Best balance for music & HT

    OK, I looked at all the threads from the past year. None addressed this issue. If there is one already that I've missed, please point me in that direction.

    I've pretty much decided to build a pair of modified Newform Research speakers from Selah Audio. Having gotten the DIY bug (just from drawing cabinet designs!), I planned on building a sub afterwards. Now a friend is going to buy my old fronts, center & sub. I have a spare pair of speakers to use during the interim, but no extra sub. So, I think I'll build a sub first.

    My question, what is the best balance of enclosure size, enclosure type (sealed, ported, PR), driver size, driver type (e.g., Tempest vs. Tumult) to integrate well with my Newforms for music and shake the house for HT? I'm leaning toward a Sonosub, but am open to a box (especially something like the pyramid shaped one I saw on Adire's website). BTW, I'm going to seal my Newforms, so their F3 will be around 60-65hz.

    Again, if there is somewhere to find previous information, please point me in that direction. Also, I appreciate the input on my last post. It helped me decide on the Newform project.

    Thanks,
    Steve V.
  • ThomasW
    Moderator Emeritus
    • Aug 2000
    • 10933

    #2
    Steve

    The choice of a sub depends on needs and wants. Tube subs can only be sealed or ported. PR's don't like anything other than vertical mounting.

    One should decide on the proper XO frequency. With a main speaker F3 in the 60Hz range (kinda high actually) the sub should have smooth output to an octave above that, so ~120Hz. I don't recommend that high a XO point though.

    The finest quality sub is an IB. A sealed design with a Qtc of 0.5 is considered 'critically damped' and has the tightest bass of any box design, some consider it a little too 'dry'. If the goal is high output in the smallest possible enclosure then PR's are the way to go.

    I've heard very little difference in the actual sound quality between good drivers. The primary difference between something like the Shiva/Tempest and the Tumalt/Braham is output levels of single drivers. Multiple Shiva/Tempests will have the same performance as a single high output driver.




    theAudioWorx
    Klone-Audio

    IB subwoofer FAQ page


    "Complicated equipment and light reflectors and various other items of hardware are enough, to my mind, to prevent the birdie from coming out." ...... Henri Cartier-Bresson

    Comment

    • JonMarsh
      Mad Max Moderator
      • Aug 2000
      • 15311

      #3
      ThomasW raises a good point about the relative performance of the moderate cost versus the "stratospheric" priced drivers. The big buck drivers can offer up to 3-4 dB more output from a single enclosure, but they require some pretty hellacious amplification, and command a premium price. In return you get a smaller woofer system, but no free lunch. We've done projects with the Stryke HE-15 and also with the Blueprint drivers (when they were available).

      Of course, another factor is enclosures- strong, stiff cabinets are a must for conventional subs, and for an IB, a convenient space for venting the rear wave is necessary. Also, the crossover implentation should not be given short shrift; like a passive crossover, it should be tuned for a specific acoustical transfer function, which may have to take driver response into account- especially for the long travel drivers. These tend to have very high voice coil inductance, which makes an additional roll off pole. Sometimes the easiest way to assure the intended response is to use an EQ unit such the Behringer to flatten the near field response of the driver, then implment the crossover with a conventional fixed slope active crossover.

      -Jon




      Earth First!
      _______________________________
      We'll screw up the other planets later....
      the AudioWorx
      Natalie P
      M8ta
      Modula Neo DCC
      Modula MT XE
      Modula Xtreme
      Isiris
      Wavecor Ardent

      SMJ
      Minerva Monitor
      Calliope
      Ardent D

      In Development...
      Isiris Mk II updates- in final test stage!
      Obi-Wan
      Saint-Saëns Symphonique/AKA SMJ-40
      Modula PWB
      Calliope CC Supreme
      Natalie P Ultra
      Natalie P Supreme
      Janus BP1 Sub


      Resistance is not futile, it is Volts divided by Amperes...
      Just ask Mr. Ohm....

      Comment

      • skvinson
        Junior Member
        • Dec 2002
        • 29

        #4
        OK, I think your replies answered more questions than they raised - but it's close!

        I thought about an IB. The good news: I have an attic above my home theater. The bad news: I live in Scottsdale (Phoenix Valley), AZ. In the summer, the attic is 140-150 degrees. Is that too hot for the drivers? I'm going to install roof vents before it gets hot again, but I don't know how much that will reduce the temperature.

        Regarding inroom subs, two drivers in one enclosure, or even two enclosures is possible. I was going to use the crossover on my receiver initially. I can choose from 50hz, 80hz, 120hz, 150hz, 200hz. I have thought of adding a Behringer unit - if not right away, soon after.

        Adire Audio suggested their "Adire Allignment" as the best compromise for music & HT. I've learned though, from other areas of audio with which I am more familiar, opinions vary. I've been talking with someone else who made the (admittedly) broad statement that sealed works best for music and vented is preferred for HT. I raise this issue here to see if there are yet other ideas, AND the reasons behind them.

        Apparently is there is more involved (e.g., crossover point, etc.). That is usually true also in other areas as well! I'm not set on a Sonotube, and I realize it is not an option if PR is the way to go. I'm also open to using some kind of EQ if that is best.

        Just looking to get input, make a decision and start the fun part!

        Steve V.

        Comment

        • Andrew Pratt
          Moderator Emeritus
          • Aug 2000
          • 16507

          #5
          In the summer, the attic is 140-150 degrees. Is that too hot for the drivers?
          Remember these drivers are often used in car trucks so heat in your roof shouldn't be a problem. If you can do an IB I'd recomend trying that option first.

          Also budget for a BFD equalizer right off the hop since you'll need one to get an acceptable in room response from any sub you build




          Comment

          • skvinson
            Junior Member
            • Dec 2002
            • 29

            #6
            Andrew,

            I called Adire and that is just what they said. People in AZ use Tempests in their trunks, so the attic won't be a problem.

            I'll plan on a BFD right away. How much do they run? Where can I find one? Another question, just what does a BFD consist of? My thought is, would it make sense to build my modified Newforms without passive crossovers - i.e., can the BFD or something similar act as a crossover and equalizer for the sub and control the Newforms too? And, would there be an advantage to that over passive crossovers in the Newforms?

            One more ... I am familiar with most brands of audio amps, but not so much with pro amps. I know Crown is supposed to be very good. QSC gets positive comments on other forums. What are some brands I should consider to drive a 2-Tempest IB?

            Steve

            Comment

            • ThomasW
              Moderator Emeritus
              • Aug 2000
              • 10933

              #7
              Steve

              From Canada to Mexico no one has reported any driver failures due to attic mounting. Popping in a few vents certainly can't hurt.

              If you want an extremely nice sub for the money try 4-15's (Tempests are a good choice) mounted in a 20" cube downfiring from the attic. The performance of this will exceed multi thousand $$$ premade subs.

              Just to a google search for Behringer DSP 1124P that will get you the EQ info. I recommend not using it for anything other than a sub EQ. It has a 'digital' signature but that's not audible from a sub

              You will want to use an active XO between the sub and the mains. Most receivers and pre/pros have these built in.

              Crown and QSC amps are fine for any sub. Be aware that almost all inexpensive prosound amps are fan cooled. For some people the fan noise is a problem . If you go with an IB you won't need an amp with cubic horsepower. 200 watts/channel is plenty




              theAudioWorx
              Klone-Audio

              IB subwoofer FAQ page


              "Complicated equipment and light reflectors and various other items of hardware are enough, to my mind, to prevent the birdie from coming out." ...... Henri Cartier-Bresson

              Comment

              • skvinson
                Junior Member
                • Dec 2002
                • 29

                #8
                Thomas,

                You wrote:
                "If you want an extremely nice sub for the money try 4-15's (Tempests are a good choice) mounted in a 20" cube downfiring from the attic."

                I plan on starting with 2-15" drivers in a 20" cube, then adding 2 more 15" drivers later. Are there other 15" drivers to consider - from a price and/or performance standpoint?

                And:


                "If you go with an IB you won't need an amp with cubic horsepower. 200 watts/channel is plenty "

                Is that 200 watts/channel into 8 ohms? Also, what is the best way to drive the 2-15's - each individually, or both in parallel? Also, does the 200 watts/channel apply to individually or parallel?

                Thanks again. I'm anxious to get started. (And my wife is glad I'm finally going to install the vents!)

                Steve V.

                Comment

                • PMazz
                  Senior Member
                  • May 2001
                  • 861

                  #9
                  PE has the Dayton 15" IB drivers on sale for $95 till Thursday!

                  Pete
                  Birth of a Media Center

                  Comment

                  • skvinson
                    Junior Member
                    • Dec 2002
                    • 29

                    #10
                    How does the Dayton 15" compare to a Tempest? In comparing various ratings, what numbers should I focus on - given my plan of an IB?

                    Also, a follow up to my amp question ... how does a plate amp compare? Would PE's ~$128 plate amp be enough to push 2-15" drivers in an IB configuration? (My room is ~16'x26' - with 8' ceilings). And, what about an Adcom GFA-555? I see a lot of people using them.

                    Thanks,
                    Steve

                    Comment

                    • ThomasW
                      Moderator Emeritus
                      • Aug 2000
                      • 10933

                      #11
                      Steve

                      I'm not a big fan of plate style amps. Unless the space and budget are limited

                      200/channel@8ohms

                      Adcom 555 is a fine IB sub amp

                      Making the cube expandable is a good idea. Some people are happy with the output of 2-15's, others feel that 4 offer the best punch. I'd make the cut outs for the additional drivers and cap them off. It's no fun to try and make more cut outs after the box is bolted in the attic.

                      The DVC 15's and the PE IB-15's are good drivers. Very similar performance and construction to the Tempest. Don't get fixated on T/S parameters any of these drivers is fine for an IB sub




                      theAudioWorx
                      Klone-Audio

                      IB subwoofer FAQ page


                      "Complicated equipment and light reflectors and various other items of hardware are enough, to my mind, to prevent the birdie from coming out." ...... Henri Cartier-Bresson

                      Comment

                      • skvinson
                        Junior Member
                        • Dec 2002
                        • 29

                        #12
                        I'm going to order 4 of the IB drivers from PE today. Since I'm getting 4 up front, that raises a question. Should I put all 4 in one box, centered between my mains, or should I put 2 each in boxes above each of my mains?

                        Steve V.

                        Comment

                        • ThomasW
                          Moderator Emeritus
                          • Aug 2000
                          • 10933

                          #13
                          We believe in the K.I.S.S. approach. That means 4 drivers mounted in one box centered between the mains.




                          theAudioWorx
                          Klone-Audio

                          IB subwoofer FAQ page


                          "Complicated equipment and light reflectors and various other items of hardware are enough, to my mind, to prevent the birdie from coming out." ...... Henri Cartier-Bresson

                          Comment

                          • JonMarsh
                            Mad Max Moderator
                            • Aug 2000
                            • 15311

                            #14
                            I'll second the idea of the Dayton 15" IB driver-- especially at the current price of $95! The Fs is in the right range, and it should need minimal or no EQ in the low end with a reasonable design. Quite a value, actaully.

                            I was just talking to ThomasW the other day, about what an amazing selection of drivers is available to the DIY builder compared with 5 or 10 years ago... this is just another example.

                            Happy Holidays!


                            -Jon




                            Earth First!
                            _______________________________
                            We'll screw up the other planets later....
                            the AudioWorx
                            Natalie P
                            M8ta
                            Modula Neo DCC
                            Modula MT XE
                            Modula Xtreme
                            Isiris
                            Wavecor Ardent

                            SMJ
                            Minerva Monitor
                            Calliope
                            Ardent D

                            In Development...
                            Isiris Mk II updates- in final test stage!
                            Obi-Wan
                            Saint-Saëns Symphonique/AKA SMJ-40
                            Modula PWB
                            Calliope CC Supreme
                            Natalie P Ultra
                            Natalie P Supreme
                            Janus BP1 Sub


                            Resistance is not futile, it is Volts divided by Amperes...
                            Just ask Mr. Ohm....

                            Comment

                            • skvinson
                              Junior Member
                              • Dec 2002
                              • 29

                              #15
                              I have just one question about the Dayton IB driver. Will it have any problems with the heat of my attic? (130 degrees+) The Tempest is used in car trunks. I doubt the Dayton IB is. Does it still have a good track record with high heat. (BTW, I also posted this on the IB page, because I need information soon. The PE sale ends today.)

                              On that same subject ... I mentioned I am installing vents to reduce the heat. A thread on the IB page mentioned someone have problems and checking his attic for air leaks. A vent is a planned "air leak." Is that going to cause a problem?

                              ... While I'm here. Jon, you suggest the Dayton's will not need much (or possibly no) EQ. Should I still get a BFD?

                              Thanks,
                              Steve V.

                              Comment

                              • JonMarsh
                                Mad Max Moderator
                                • Aug 2000
                                • 15311

                                #16
                                Adhesives, cone materials (kevlar impregnated paper) and surrounds are pretty similar between these and the Adires. I'd expect their behavior with regards to temperature tolerance would be quite similar.

                                There's two reasons to need EQ in a sub. One is because of inherent issues with the driver characteristics, which cause predictable (and mild) frequency response deficits that are easily corrected with small dollops of EQ. In this category would be

                                1) having a driver with high VC inductance causing roll off above 75 Hz (Stryke HE-15, BPD 1503, 1203, Titanic MkII's);

                                2) having a somewhat over damped driver (Q under 0.4 for IB, etc) or tuning a ported system below the normal box/driver resonance in order to control or extend the bottom end (my X1 SLAMM Klones, the Aerial Stryke sub using the HE-15, my woofer modules for the line array) which requires a small shelving EQ boost to flatten the in room response (assuming the driver is tuned to handle the power and output.

                                3) having a roll off in the upper pass band of a manifold array IB due to differences in driver mounting

                                The other reason is to try to compensate for room acoustics and placement issues, to correct the response at the listening position. Personally, I think that's a questionable practice, because if the speaker's nearfield response has been otherwise engineered to be fairly flat, then EQ'ing the farfield response at one point will mess it up at others. This is where the art of room design, speaker placement, and listener placement becomes important. There may be times when it seems like unavoidable compromises in room positioning are required, which can then only be dealt with by EQ, but this isn't a practice I recommend. As my grandpappy taught me, "Acoustical solutions for Acoustial problems".

                                Bottom line, Steve, is you may not really need any EQ to get the nearfield response of a short manifold IB (all drivers equal distance) to get a very smooth, flat, extended response. You might "want" it to assert some fine tuning for taste, a few dB in the very deep bottom end (20 Hz nad below) or the afore mentioned positioning issues.

                                What I would do in your shoes is get a good "bargain mic" like the Behringer ECM8000, pair it with an M-Audio mic preamp, and using utilities like nchtone and TrueRTA evaluate your setup nearfield and at the listening position. You're going to need those tools anyway if you want to do a tight calibration of the sub in room.

                                Happy Holidays!

                                _Jon




                                Earth First!
                                _______________________________
                                We'll screw up the other planets later....
                                the AudioWorx
                                Natalie P
                                M8ta
                                Modula Neo DCC
                                Modula MT XE
                                Modula Xtreme
                                Isiris
                                Wavecor Ardent

                                SMJ
                                Minerva Monitor
                                Calliope
                                Ardent D

                                In Development...
                                Isiris Mk II updates- in final test stage!
                                Obi-Wan
                                Saint-Saëns Symphonique/AKA SMJ-40
                                Modula PWB
                                Calliope CC Supreme
                                Natalie P Ultra
                                Natalie P Supreme
                                Janus BP1 Sub


                                Resistance is not futile, it is Volts divided by Amperes...
                                Just ask Mr. Ohm....

                                Comment

                                • skvinson
                                  Junior Member
                                  • Dec 2002
                                  • 29

                                  #17
                                  Jon,

                                  Thanks again. I'm off to order my Dayton IB drivers! I'll pick up the other items you mentioned pretty soon. (Can I quote you when my wife asks, "Why do you need these?"?)

                                  One more question. (I can't guarantee it will be my last on this project, but we'll see.) Do I leave the entire bottom of my 20" cube open and vent it through a 20x20 hole in the ceiling?

                                  Thanks,
                                  Steve V.

                                  Comment

                                  • Andrew Pratt
                                    Moderator Emeritus
                                    • Aug 2000
                                    • 16507

                                    #18
                                    Oh oh looks like another guys about to jump of the deep end:LOL:

                                    Yes You'd leave the 20"*20" bottom open. If you like you could cover it with grill cloth etc




                                    Comment

                                    • Dennis H
                                      Ultra Senior Member
                                      • Aug 2002
                                      • 3798

                                      #19
                                      Harman has a number of good whitepapers on acoustics and speaker placement. Short version, they recommend spreading out several subs rather than locating them all at the same point. While they didn't specifically test this configuration, reading between the lines in several of their papers, I believe the smoothest (not the highest output) configuration for 4 ceiling mounted drivers would be to use the Cardas golden mean method in two dimensions. Draw diagonal lines from corner to corner and measure .276 of the line length from each corner. Harman did test 4 speakers at the quarter points and it was the smoothest of any 4 speaker configuration they tested, over the widest listening area. However they concluded it wasn't practical for box subs in most rooms so they concentrated on locations on the walls that were almost as good. Center of the 4 walls was pretty good. In another white paper on stereo placement, they showed how moving the speakers a little past the quarter point was best so Cardas' .276 is consistent.

                                      Comment

                                      • skvinson
                                        Junior Member
                                        • Dec 2002
                                        • 29

                                        #20
                                        Dennis,

                                        I downloaded the HK paper. I'll read through it. I was content with Thomas' K.I.S.S. suggestion. Now you have to rock the boat! One interesting thing, I mentioned to my wife that IB subs could be mounted individually and facing forward. I said most people only did this for wall-mounting. She said she would be fine with it in the ceiling, if it looked nice (e.g., some white speaker grills). So, if the Cardas arrangement does seem best, I could mount two speakers out from the corners. ... I just know the IB forum suggests keeping them on the same plane as the front speakers. Why can't there ever be just one answer???

                                        Thomas (or anyone),

                                        A question about your amplifier suggestion. You recommended 200 watts/channel into 8 ohms. I ended up going with the Dayton 15" IB drivers. Their power rating for IB applications is 100 watts RMS and 140 watts Max. I plan on running them in parallel (4 ohms). Do I need something that does 200 into 8 ohms? That would be 300-400 into 4 ohms. Is your 200 watt/8 ohm suggestion factoring in headroom? Is that how much headroom I should have? Also, do I need an amp that will perform down to 2 ohms? I know full range speakers will dip from their nominal rating. Is that the case with an IB sub?

                                        BTW. I decided to go with 2 drivers initially, so I'm looking at various monoblocks (e.g., Marantz MA-700, or even 500). OTOH, I might find a decent three channel amp and plan on powering my Newforms with the other two channels. That is why I ask about the necessity of being stable into 2 ohms. Not all audio amps will handle that easily.

                                        As always, thanks! When the walls are shaking, I will be forever grateful!!

                                        Steve V.

                                        Comment

                                        • ThomasW
                                          Moderator Emeritus
                                          • Aug 2000
                                          • 10933

                                          #21
                                          Steve

                                          I wouldn't mount the ceiling drivers in a line especially if there is a chance of needing to add more drivers. Use a box and make cutouts for the additional drivers.

                                          Centering the driver box between the mains allows for decreased potentional smearing of the stereo image if higher XO points are used. It also helps time align the sub with the mains and decreases the potentional for cancelations (nulls) compared to having 2 boxes/sources.

                                          Many of the lower buck monoblocks are a little lacking in the quality dept. Check places like audiogon THIS looks like a good buy for a sub amp. THESE and THESE are good sub amps as well.

                                          Unless you use a prosound amp or something with a massively stiff power supply like those in Aragon amps I wouldn't create a 2 ohm load.

                                          As far as 3 channel amps are concerned I wouldn't want my mains sharing a common power supply with a sub.




                                          theAudioWorx
                                          Klone-Audio

                                          IB subwoofer FAQ page


                                          "Complicated equipment and light reflectors and various other items of hardware are enough, to my mind, to prevent the birdie from coming out." ...... Henri Cartier-Bresson

                                          Comment

                                          • skvinson
                                            Junior Member
                                            • Dec 2002
                                            • 29

                                            #22
                                            Thomas,

                                            Thanks for the positioning advice. I like the idea of a box that is vented between the speakers best, so I'm glad it is a good choice.

                                            Thanks also for the specific amp recommendations. I did not realize Yamaha had such amps.

                                            You say not to create a 2 ohm load (unless I use a prosound amp or something like an Aragon). Are you saying that running the two drivers off one channel (i.e., a 4 ohm load) WILL dip to 2 ohms?

                                            What are the advantages/disadvantages to running both speakers together (4 ohms) or separately (8 ohms)?

                                            Thanks,
                                            Steve V.

                                            Comment

                                            • ThomasW
                                              Moderator Emeritus
                                              • Aug 2000
                                              • 10933

                                              #23
                                              Steve

                                              The older Yamaha amps have a tank-like build and a reputation for good reliability.

                                              Most home audio amps aren't happy with 2 ohm loads. I'd wire one PE IB speaker/channel (8ohm load) if using just a pair of speakers, and create a 4 ohm load /channel if using 4 of the PR IB drivers




                                              theAudioWorx
                                              Klone-Audio

                                              IB subwoofer FAQ page


                                              "Complicated equipment and light reflectors and various other items of hardware are enough, to my mind, to prevent the birdie from coming out." ...... Henri Cartier-Bresson

                                              Comment

                                              • skvinson
                                                Junior Member
                                                • Dec 2002
                                                • 29

                                                #24
                                                I'm looking at getting a Samson S700. They are 240 watts/channel (8 ohms) and 350 watts/channel (4 ohms). I'm checking to see if they are stable into 2 ohms. Again, I'm assuming that if I add two more drivers later (two on each channel - 4 ohms), the load will dip down around 2 ohms. Is that right? If not, I don't have to worry about that spec. I just want to be able to keep whatever amp I buy now, if I add two more 15's later.

                                                SVS sells them with their subs, and I hear very good things about the combo. I've found them as low as $340 delivered.

                                                Any thoughts?

                                                Steve V.

                                                Comment

                                                • ThomasW
                                                  Moderator Emeritus
                                                  • Aug 2000
                                                  • 10933

                                                  #25
                                                  The low end prosound amps are all fan cooled. This includes the Samson. Whether or not you can/want to live with the fan noise is something to consider. If the amp can be put in a different room/area then the noise is no big deal. If it has to live in the listening room then the noise maybe a bother.

                                                  Samson are similar to Mackie or the other low end prosound amps. They all sacrifice by providing relatively high power in exchange for lower quality parts and construction. They're unproven in the longterm resale market so I question whether or not they are a good investment. Personally I buy power amps that are a known quantity, because they are one piece of gear I tend to keep for years and years.

                                                  Crown makes a line of lower cost prosound amps that offer their 5yr no fault warranty. They too are fan cooled. Understand that any of these low cost switching amps are not recommended for any HT use other than powering subs due to their noticible sonic signature




                                                  theAudioWorx
                                                  Klone-Audio

                                                  IB subwoofer FAQ page


                                                  "Complicated equipment and light reflectors and various other items of hardware are enough, to my mind, to prevent the birdie from coming out." ...... Henri Cartier-Bresson

                                                  Comment

                                                  • JonMarsh
                                                    Mad Max Moderator
                                                    • Aug 2000
                                                    • 15311

                                                    #26
                                                    Something to think about.... take these commens with a grain of salt, I mean no offense. But....

                                                    One of the things I used to do in the 70's was modify/rebuild/custom build Dyna 400's with some serious upgrades to the power supply and doubling the number of output transistors. The power supply transformer that came with these amplifiers was quite reasonable- not the limiting factor. But the capacitor bypass, like most amps of it's time, and many today, was. For the original Dyna ST400, the bypass was two 10,000 uF caps. I normally punched that out to 100,000 uF total (in a new chasis), and added about 200 uF of polypropylene bypass (or polycarbonate if the customer wanted to save a few bucks).

                                                    This made a huge difference in the dynamics of the amplifier, especially in the bottom end at high power, and in it's overall sense of ease and combined macro and micro dynamics. 8O No, all amps don't sound the same, especially when you start pushing them hard.

                                                    Fast forward, and my friend C. Hansen has updated the Ayre V1 to the V1x by (guess what, among other things) over doubling the total supply capacitance- now it's up to 280,000 uF. Does it make a difference? On the bench, hardle discernable. :? Audibly? Well, according the reviewers, it definitely does. In the bottom end. 8)

                                                    So it's with a certain sense of dislocation or "What the ... ??" :roll: when I see SO many people building some pretty heavy duty subs, and hooking them up to some rather mediocre amplifiers. You don't need high tech circuits or non feedback topologies or slew rate out the wazoo for a sub amp. You DO need a rock solid power supply- something the relatively low end pro amps don't have any more than their predecessors like the Phase Linear 400 or old Crown DC300A's had.

                                                    Now, I understand the economics of the Pro Sound market- I used to design for it in the late 70's. And dollars for the watt is the "Prime Directive". And modern long voice coil woofers certainly do like the watts- witness drivers like the original BPD1203/1503 and the AV12 which really should be fed with 500 - 1,000 watts to realize their full potential. (Optimum for the BPD1203 before excursion limits set in is about 750 watts in the low bass). But, our own experience suggests that for a high end HT/Music setup, they've got to be reasonably good quality watts...

                                                    You can get DJ "pro" CD players, which are built ruggedly, and have some good features for the performing market- but you probably wouldn't want one in your home audio system as your main source.

                                                    So, I'm not just being an audio snob when I suggest that you'll get the most "quality" out of the bottom end of your system if you use "quality" amplification. Sometimes I wonder when folks say that big HT subs aren't good for music setups, if the electronics used (as well as the setup) aren't a factor in this judgement.

                                                    Just my $0.02. I can understand that the inexpensive pro amp might be a necessary stopgap, but maybe buing a used Aragon or Bryston might be another choice to consider.

                                                    Happy Holidays!

                                                    Jon




                                                    Earth First!
                                                    _______________________________
                                                    We'll screw up the other planets later....
                                                    the AudioWorx
                                                    Natalie P
                                                    M8ta
                                                    Modula Neo DCC
                                                    Modula MT XE
                                                    Modula Xtreme
                                                    Isiris
                                                    Wavecor Ardent

                                                    SMJ
                                                    Minerva Monitor
                                                    Calliope
                                                    Ardent D

                                                    In Development...
                                                    Isiris Mk II updates- in final test stage!
                                                    Obi-Wan
                                                    Saint-Saëns Symphonique/AKA SMJ-40
                                                    Modula PWB
                                                    Calliope CC Supreme
                                                    Natalie P Ultra
                                                    Natalie P Supreme
                                                    Janus BP1 Sub


                                                    Resistance is not futile, it is Volts divided by Amperes...
                                                    Just ask Mr. Ohm....

                                                    Comment

                                                    • skvinson
                                                      Junior Member
                                                      • Dec 2002
                                                      • 29

                                                      #27
                                                      Thomas & Jon,

                                                      Thanks again. ... Seems like I've said that a lot. I know I'll say it even more when this project is done and I can HEAR the results!

                                                      Thomas' earlier suggestion & last post already had me leaning back toward the Adcom GFA-555. As far as Bryston & Aragon, I have a high opinion of those lines. Does anyone know offhand how the Adcom compares in terms of capacitance and other relevant specs? I'm trying find info, but Adcom no longer has specs on their site for the 555. Used Bryston (4B) & Aragon (4004) that put out 200 watts/channel run about twice as much as a used 555. I never mind saving money (because there is always something else to spend it on!), but I also want to do this right.

                                                      Steve V.

                                                      Comment

                                                      • skvinson
                                                        Junior Member
                                                        • Dec 2002
                                                        • 29

                                                        #28
                                                        I just got a Bryston 4B on Ebay. Not much more than some Adcom 555's were going for, and it still has 6 years of warranty left.

                                                        Things are coming together...

                                                        Comment

                                                        • ThomasW
                                                          Moderator Emeritus
                                                          • Aug 2000
                                                          • 10933

                                                          #29
                                                          Good shopping.....

                                                          The interesting about Bryston gear is if you ever have it upgraded. You get a new 20yr warranty




                                                          theAudioWorx
                                                          Klone-Audio

                                                          IB subwoofer FAQ page


                                                          "Complicated equipment and light reflectors and various other items of hardware are enough, to my mind, to prevent the birdie from coming out." ...... Henri Cartier-Bresson

                                                          Comment

                                                          • Dennis H
                                                            Ultra Senior Member
                                                            • Aug 2002
                                                            • 3798

                                                            #30
                                                            Thomas and Jon,

                                                            Have you heard the QSC DCA series? Other people have reported that they sound good - no "pro" sonic signature - but I haven't listened myself.

                                                            Comment

                                                            • skvinson
                                                              Junior Member
                                                              • Dec 2002
                                                              • 29

                                                              #31
                                                              Thomas,

                                                              Thanks for the info. I saw one 4B seller mentioned having his amp in for a "tune up." I didn't know what that entailed, and planned on contacting Bryston. I didn't realize it could be upgraded and given a new warranty. I will definitely check on that.

                                                              Dennis,

                                                              I have not heard a QSC DCA series amp, but there is a long thread about QSC on avsforum:

                                                              http://www.avsforum.com/avs-vb/showthread.php?s=&threadid=159031

                                                              One thing people mention is that even the DCA series needs a quieter fan if it is going to be used in the same room. They are coming out with a new series that is more geared to HT. Should be out first of 2003.

                                                              Comment

                                                              • skvinson
                                                                Junior Member
                                                                • Dec 2002
                                                                • 29

                                                                #32
                                                                Just an FYI ... I contacted Bryston. They do not offer any upgrades and there is no way to restart their warranty. They do not recommend sending an amp in for a "tune up." They will check it out, but will charge a $50 bench fee.

                                                                So, they have a great warranty, but there are limits.

                                                                Steve V.

                                                                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 "|||"