SACD Bass Management Woes

Will the Outlaw ICBM work for me?

When I balance my 7+1 speakers & sub for 75dB using the noise generator in my receiver (B&K)-- all is well for THX movies.

Then, when I put on my SACD - the sub is about 13dB lower volume than the remaining channels (almost zero bass).

I can fix the SACD by balancing the speakers using the SACD noise generator - but then the THX bass is 13dB too high !!!

I think what I need to do is attenuate the sub output from the Sony SACD by 13dB

The ICBM does include a subwoofer trim control that could allow you to set the sub higher on the analog (SACD). The manual shows the trim knob control ranging from "MIN" to "+9dB"

------------------
gonk -- Saloon Links | Pre/Pro Comparison Chart | 950 Review

So you could use it to add some gain to your sub, without screwing with any of the crossover stuff... but you'd still be 4 dB shy. Isn't there some kind of preamp you could buy to add 13 dB to the sub channel, or perhaps some attenuators to lower your other channels 13 dB? The ICBM seems to be overkill for your purpose.

Or perhaps, if you're lucky, there is a gain adjustment in your SACD player for the sub channel.

------------------
Matthew J. Hill
matt@idsi.net

There are gain adjustments in my pre-amp and the Sony SACD - but neither gets close to the 13dB.

Also, B&K told me I really don't want to be doing that. Too much gain results in audible noise.

I think it's a mis-match between THX specs and SACD specs.

Dennis: You're on to something. I don't use/have an SACD or DVD-Audio player but I did just buy a new Denon 3803 receiver. One of the setup parameters is strictly for subwoofer level compensation when using the external 7.1 inputs. You can add up to 15 db of volume. So obviously, there is a spec difference...

Low LFE seems to be an issue with many DVD-A and SACD players from different manufacturers. I have a Pioneer 45A that has the exact same problem.

If you hunt around at the Home Theatre Forum there is quite a bit of discussion on the subject.

I have yet to hear a definitive explanation for why this is happenning, although I have an open case with Pioneer on the matter.

FTR, I am thinking of getting an ICBM to work around the problem.


BL

Well!!! It seems I've been researching this forever instead of listening to music.

But, alas - still no answer. It is epidemic, however. Folks everywhere are writing into forums and asking "Why no bass?" -- and a common response is buy an outlaw icbm.

However, I did write into a home theater magazine and got a response which I don't think addresses the problem.

I've concluded the two systems (Dolby/THX and SACD/DVD-A) cannot coexist on the same receiver with a sub. The workaround is to set up the SACD as a 5.0 instead of a 5.1 with large fronts. I suppose you could also wire the sub with high level outputs if you have small fronts.

It definately seems to be a hardware issue. I never got past the basic setup (white noise sound equalization). I can either balance the SACD or the THX but not both at the same time.

They co-exist fine in my system. My Lexicon MC-12 has an analogue bypass for the 5.1 analogue inputs. I run a DVD-A and an SACD player to it through an external switch-box. I have the output levels of the MC-12 (which are seperately configurable for the 5.1 bypass mode, and in fact for all modes) set to calibrated levels from my SACD player, then I use the DVD-A player's level controls to tweak the levels for DVD-A.

------------------
Nigel Pond
SMR Home Theatre
SMR Forums
SMR Group
HighFidelityReview

[This message has been edited by ukexpat (edited January 20, 2003).]

For us mortals that don't have a Lexicon, b/m is an issue. Please see my post on the Denon universal player I just bought. Fully digital b/m, but I haven't licked the problem fully even yet.

I also have the DV-45A, and no bass probs. Of course, that because it had no b/m! I used an AudioControl PCA Series III to cross the mains over. Worked pretty well, but not as well as an ICBM.