Axiom Home Page Forums General Discussion Technical Questions Weak SWFR output on SACD/DVD-A multichannel

I got a new Denon DVD-757 universal player (identical to 1930CI), and SWFR output is about 20db too weak for all SACD and DVD-A multichannel discs. I've heard this is a standardization problem whereby content producers and player mfgs master the SWFR track -10db, -15db, or -20db down (nobody seems to know exactly), but the player and amp mfgs don't provide sufficient gain to compensate. Just wanted anybody's comments.

Equipment: M60, VP150, QS8, Hsu VTF-3R, Yamaha RX-V1400 receiver, Denon DVD-757 universal player.

Interconnect: 6-channel analog

Test config: SACD pink noise calibration disc, ref level 75db, Radio Shack analog SPL meter. Player is configured for multichannel analog out, SWFR "on", all other speakers "small", bass enhancer = "on" (but this has no effect).

When using DVD-757 player built-in pink noise, SWFR output is about correct. When playing multichannel SACD or DVD-A material, SWFR output is about -20db too weak.

The RX-V1400 has a discrete gain control for SWFR analog in, but it's limited to +10db. Player output trims are attenuate only -- 0 to -12db. Only workable solution is setting amp SWFR gain at +10db, setting all player output channels (except SWFR) at -10db or -12 db, turning up amp master volume to compensate for lower player output. This gives a combined effective SWFR gain of 20 to 22db, which reads about correct on the SPL meter when playing SACD-sourced pink noise, and also sounds aesthetically correct for SACD/DVD-A music material.

Also DVD-A discs have a DD 5.1 compatibility layer, so an additional verification is switching between the DD 5.1 and multichannel DVD-A version of the same material. Only with the above compensations (about 20 db on my system) is the DVD-A bass level about equal to the DD 5.1 bass level (relative to the other channels at a given volume level). DD 5.1 bass level calibrated using DVE disc and SPL meter.

DD 5.1 and DTS 5.1 discs on the same player don't have this problem. That's expected, as the interconnect is Toslink, and the Dolby SWFR recording standard is -10db, boosted automatically by +10db by the decoder or amp.

Has anyone else using multichannel SACD/DVD-A discs encountered this problem?

Have you adjusted the levels in the player? I ran into a similar problem with mine.

I haven't, but have read many reports of this issue. I have read that usually enabling bass management on the SACD player will further attenuate the sub signal down, sending all the redirected bass from the other channels may cause the analog signal to be overdriven- thus it is cut by the player to avoid this.

There is a good thread over at AVSforum.com about this issue.

http://www.avsforum.com/avs-vb/showthread.php?t=748147

Player levels on the Denon DVD-757 (and 1930CI) are attenuate only -- no boost. IOW each 5.1 channel is adjustable from 0db to -12db.

Reaching proper SWFR output on my system requires maxing out the amplifier's discrete SWFR multichannel gain at +10db, PLUS maxing out the player output levels at FULL MINUS: -12db, except for player SWFR which stays at 0db. When amp volume is turned up further, the -12db on the player 5 channels in effect gives +12db additional boost to the SWFR output.

The effective total boost of about +22db on the SWFR channel when playing SACD and DVD-A using 6-ch analog interconnects.

I've heard the argument about bass redirection; I don't fully understand or buy it. Typical line out spec for 5.1 analog is 2 volts rms, max -- for both SWFR and 5 main channels.

Accomodating the contribution to SWFR output from possible bass redirection shouldn't require cutting the SWFR output. You'd know the max possible contribution from fully-driven inputs (inc'l from redirection) -- that would set the max Vrms on the SWFR output jack.

On my system, even though player bass redirection is in effect, the player SWFR output (LFE + redirected bass) is still far too weak.

It's not just the LFE (or SWFR, depending on terminology) channel from SACD/DVD-A is weak, but the cumulative player SWFR output (LFE plus redirected bass) is also weak.

Very common problem. I work around it in a similar fashion.

I have a Denon DV-1920A that I use, and have the same problem. Using its analog outputs on SACD material, the sub level is about 10db too cold, and the player only allows for negative adjustment. So you can set all of the other levels -8 or -9 db, but then you have to crank up your prepro/avr to compensate and not forget to turn the volume back down before switching sources.

In my case, my AVR (Pioneer Elite VSX-43TX) is able to compensate. It allows you to adjust the calibration levels for just the analog inputs.

I set the sub level (on the back of the sub) a bit on the high side, so that during the general calibration my AVR is set at like -4 or -5 on the sub channel. Then I calibrate using the SACD player's test tones, and bump the level on the AVR on the analog inputs up to +5 or +6 on the sub channel. That has fixed the problem for me.

One problem I'm having is that I want to replace my AVR with a true pre-processor, but I can't find any that let you do this. It looks like an Outlaw 990/970 might be able to handle it, as they can do bass management on the analog inputs. Though no specific level compensation on the analog inputs, however.

Another item you could look into is the discontinued Outlaw ICBM. It's my understanding that it had a level control for the sub that allowed +db adjustments.

Peter, thanks for the reply. I see I'm not the only one using this technique to work around the problem.

An odd twist is my Denon player's built-in test tones don't exhibit the problem; player SWFR output level is about right in that case. It's only when playing actual SACD or DVD-A material the player SWFR output is attenuated about 20 db. Very strange.

From a philosophical standpoint, turning down my player 5 main channels -12 db (leaving SWFR at 0db) then turning up the amp master volume to compensate is hurting the noise floor by that amount. Yet isn't that a supposed advantage of high resolution formats?

At least it sounds OK, just irks me to peg the discrete amp SWFR gain on full plus and peg the player outputs on full minus to get proper bass.

Like you I could turn the sub volume knob up higher, on the amp turn down the other sources (except analog multichannel), that would buy a few more db.

It's just outlandish to jump through such hoops. No wonder SACD and DVD-A are struggling formats. The sadest part of all is, a well-mixed multichannel SACD or DVD-A album played on a properly-calibrated system is outstanding. Yet most people will never experience this. Industry mismanagement and poor standardization contribute to the sad situation.

One solution to the bass management problems in these players is to upgrade to a player that has digital output for SACD and DVDA. Digital outputs for these formats include: firewire (IEEE 1394 or iLink), Denon Link III, HDMI version 2 for SACD or version 1 for DVDA.
It its too bad that players with these outputs are usually more than $700 US.
I am lucky enough to have the Denon DVD-2930 (Denon link III) with the AVR-4806. This is one smokin' combination for SACD and DVDAs.

Doesn't the Oppo 970 output SACD/DVD-A through HDMI?

Priced at only $150, it seems like a bargain.

Yes you are correct. The Oppo 970 HD is an excellant alternative. I forgot about it. The 970 outputs lpcm over HDMI. BTW I emailed Oppo to ask which player they recommended for SACD and DVDA use. They recommended the 970 rather than the 981!

I opted for the DVD-2930 because it can output DSD. I let my 4806 do the conversion. The 4806 probably does a little better with the conversion but I doubt it makes much difference.

Thanks for pointing out the price. It is indeed a steal.

I was sort of throwing out an idea in case the OP wanted a less expensive alternative. Happy listening!

So if I spring for a Denon DVD/SACD player that has the V3 DenonLink, and an appropriate Denon receiver, then the receiver can do the bass management via the digital connection. Cool. Do these players also suffer from decreased sub levels?

Does anyone know of a SACD/DVD-A player that does has normal sub output on the analog channels? I'd happily buy one if it meant that I didn't have to overadjust my system to compensate for it. I love the look of the Oppos, and they have a stellar reputation, but how is their sub output?

Oh, and the manual for my Denon 1920 talks about a 'Bass Enhancement' feature that's supposed to work on the 5.1 outputs, but it doesn't do anything, as confirmed with an SPL meter.

I knew I should have bought an Outlaw ICBM before they were discontinued. Solve all the Bass Management issues, and have sub channel level control.

Before changing up my system I had the Denon 3910 and the 3805 setup using the Denon link, the bass was excellent, no loss at all. Now I seemed to have lost some bass through my HDMI connection with my Toshiba HDDVD, but have had no problem adjusting it through my 4806.