Do you think you need a subwoofer?

Hi enginedr1960,

     It sounds like you have a combo system, as I do, used for both music and HT.  I was a bit surprised you use VTL 100 mono-block amps in your system.  I would imagine they're great for music but less than ideal for HT since tube wear is increased.  Or, do you have your system configured to utilize separate solid-state amps for HT duties.  Could you clarify this?

     
     I understand how your Outlaw pre-pro is used for decoding surround sound codecs for HT.  But I'm not certain how you utilize the DSPeaker antimode 2.0 and exactly what it does.  Could you explain in more detail how your DSP controlled stereo bass works?  

     I've been trying to spread the word on distributed bass arrays using 4 subs here on Audiogon ever since I personally discovered how well it has improved bass reproduction in my system.  After a lot of research, I intellectually understand the acoustical physics and the theories on how and why it works.  But I still think there is no substitute for auditioning a good DBA in person for appreciating how impressively it reproduces bass in any room without the use of mics, room analyzing/room correcting software, equalizers or room treatments.  

     Based on the large number of posts I've read from members who seem to think their system bass response needs can be solved if they just get the right brand or model of sub, it's fairly obvious that many are unaware of the DBA concept.
     You're actually one of the first Audiogon members I've encountered thus far that also utilizes  a DBA.  I'm glad we're now aware we both use slightly different DBAs and can share experiences and information with each other.

Thanks,
  Tim 

Hi Tim I use the VTL 100 amps for HT and 2 channel music . as for tube life I am using 2 KT120 tubes in each amp if they wear out so be it . There is plenty more of them available . I use the DSPeaker as a room correction for 500hrz and down for the main speaker and all 4 subs . This device works by using a microphone to measure the room response from the listening area then it runs a series of tones across the L/f range and applies a correction . I have frequency bump @  50hrz and the DSPeaker corrects that . The biggest improvement with adding the 2 extra subs is that the bass response all through out the room is much more even and the tonal quality is better. RC      

Hi Doc,

     I like your commitment to all out sound quality by using your tube VTL 100s for both 2 channel and HT.  I just have a few questions:

1. Have you tried lowering the sub crossover frequency  closer to the 50 hz lower frequency cutoff on your amps?

 DSPeaker room correction for 500 hz  and down seems somewhat high and broad to me.  I consider 500 hz to be in the lower mid-range spectrum rather than the bass spectrum.  

2. Have you tried running your system with all room correction units removed?

I think you'll find your system's bass response will be very good without it.  I would recommend setting each of your sub's crossover setting initially at 60 hz and then experimenting with even lower settings of 50 or even 40 hz.  A setting of 50 hz may not be good in your room due to your room having a frequency bump @  50 hz.  The downsize of this approach is that the level and cutoff freq. would need to be set individually for each sub.  But this should only need to be done once at the precise setup/calibration stage.

Thanks,
  Tim

Hi Tim the problem I have is I am limited on space to play with optimum sub placement . I use my subs in stereo the front subs are set to 60hrz and the rears are set to 45hrz . The DSPeaker makes this arrangement work well . the DSP has a bypass mode so you can hear the difference the correction is doing . I have had the DSP for 3 years running 2 stereo subs with great success adding the rear subs improved the whole system . As for the DSP being transparent I have been tweeking both my digital and analog front ends and I can discern the changes . The DSPeaker and my custom Bent Audio / Dave Slagle AVC volume control pre amp makes low volume listening sublime .Tim if you want to understand the DSPeaker there is much info on it              

Hi Doc,

     I believe you live in a Manhattan postage stamp so lack of space and the need to listen at lower volumes are issues.  I hear the penthouse at Trump Towers may be available soon. Just something to consider if you want more room, fewer neighbors and solid gold toilets.

      I now understand you use your DSPeaker for 600 hz and below system wide.  The upper range of this (specifically 50 -600 hz) is reproduced by your main Ohm Walsh speakers and not your subs; you run your subs in stereo with the front 2 subs handling 60 hz and lower and the rear 2 subs handling 45 hz and lower.  I think you're aware that there is some overlap with both your front 2 subs and your main speakers reproducing frequencies between 50-60 hz.  But your DSPeaker likely adjusts output in this small range to smooth out response.  Your clarification now makes your system a lot more sensible to me.  

     My goal is mainly to learn how your system functions and not to criticize a configuration that obviously works so well for you.  I know it's not easy to construct a system that sounds good at lower volumes.  It's been well known for decades that human perceived loudness of very low and very high frequencies, in comparison to mid-range frequencies, decreases as volume is decreased.  This was the reason some older audio components (1980s to 90s) had 'loudness' buttons and controls that boosted these frequencies to compensate.

     Perhaps the reason your system sounds so good to you at lower volumes is because your DSPeaker incorporates a 'loudness countour' that is boosting the lowest and highest frequencies relative to the mid-range frequencies as you lower the overall volume of your system.  This is only speculation on my part but I think it's a reasonable assumption given your results utilizing this DSP tool.

Tim