DV-45A Sub level question (1 Viewer)

[Brian L]

That's because there is no standard as how to record bass or utilize the LFE channel.BTW you find the same thing on CDs too, no 2 cd's have the same exact bass contents right?

While I would certainly agree with that premise, I think some of the differences go beyond differences in what the engineer/artist wanted to do for artistic purposes.

While I am happy as a clam that in my system, I am able to calibrate to get what appear to be accurate results on all media without needing to make drastic adjustments (Weather Report DVD-A accepted), I keep wondering why the sub level was different, and why I did NOT get a difference when using the Chesky disk and comparing the DD and DVD-A version of the test tones.

I will get back to you when I test with the Telarc DVD-A tones (which methinks will further confuse the issue!).

BGL

 

[Lewis Besze]

I will get back to you when I test with the Telarc DVD-A tones (which methinks will further confuse the issue!).

Not necessarily,this will tell us about not only the player but the tones as well,I think there is much to blame on the inconsistency of these tones.

 

[Brian L]

Not necessarily,this will tell us about not only the player but the tones as well,I think there is much to blame on the inconsistency of these tones.

I would certainly agree with that. I don't know if I have two sets of DD tones among all the test discs I own (Avia, VE, Ultimate DVD, Delos Surround Spectacular, Chesky, Telarc, and lets not forget DVD's with the THX Optimizer) that are dead nuts equal.

BGL

 

[Phil_DC]

I have the 47Ai, I found that the easiest way to fix the bass was just to set the speakers to fixed + small and install a Bass management controller. I use the M&K BMC 5.1 Mini seen here: BMC Mini

There is also the Outlaw ICBM which a lot of people are using either will do the trick.

Unfortunately with the current crop of DVD-A/SACD players out there a bass management controller is a virtual necessity. However the new ones coming out have supposedly better bass management built in,only time will tell.

 

[Brian L]

I have the 47Ai, I found that the easiest way to fix the bass was just to set the speakers to fixed + small and install a Bass management controller.

I do not know the MK product, but wouldn't you want your 47Ai set to all large/sub on for compatibility with an external crossover?

Thats what is required in a 45A with an ICBM.

BGL

 

[Phil_DC]

It was recommended to me by someone else to set them to small so I did and it sounds pretty damn good.

I will have to change them to large and see what kind of difference it makes.

Thanks for the tip!

 

[Brian L]

It was recommended to me by someone else to set them to small so I did and it sounds pretty damn good.

I guess it depends on the crossover frequncy in the player vs. the external crossover.

I know that the 45a is 100hz, so if I set to small, I would not really be getting any benefit from the ICBM, which I set to 80.

But as you correctly stated, its the ears that are the final judge.

BGL

 

[Kevin C Brown]

Hee, hee.

In this case, 2 wrongs did make a right.

Remember, this is how I got my levels balanced for DD/DTS/CD digitally from the player to the pre/pro vs SACD/DVD-A analogly to the pre/pro:

I specifically adjusted my sub's volume level such that I needed about a -5 dB setting for the sub's level in my pre/pro (with Avia). So then when I adjusted the DVD-A level with the Chesky disc, I magically got about +5 to +6 sub level in the player. Everything balanced, and the 10 dB was right there for all to see.

But this assumed that the analog inputs on the 950 were *not* affected by the levels in the player. But Lewis mentioned that they are. (They also are in the MC-8.) [This still seems a little fishy to me, in that I always thought that those level differences were in the DSP part of the processor, but anyway...]

So when I went back through today, I took out the -5 and +5 and essentially I get balanced levels in both the DD/DTS/CD and DVD-A/SACD case with a sub level in both cases about +/- 1 dB for the digital values in the pre/pro, and the analog values in the player.

So in effect, I was creating the 10 dB by how I originally set things up. Did work right, mind you, just didn't need to do it that way. (-5 + +5 = ... 0)

Now, the one oddity I did find, and this is tough to explain, is that when I compared the analog output from the player vs passing it digitally to my pre/pro, Avia balanced both ways with DD. That's how it should be.

When I used the Chesksy disc, the analog DD feed matched the analog DVD-A test tones, but the digital feed of the DD test tones gave me a sub level that was about 10 dB too low. That has to do with the DD decoder in the player, but why in one case would it be OK, and the other not? So that's one question, but remember, me personally, I had never really used the DD feed from the Chesky disc anyway.


So OK, but then if the 10 dB difference doesn't have to be compensated for by us, then why do all those people feel that the DVD-A/SACD sub output from the 45a, 47ai, 2900 is too low? The only conclusion I can draw here, is that at least on the 45a and 47ai, we all do know that the sub test tone is too low anyway. On the 2900 too (in a specific mode) maybe?

 

[Lewis Besze]

So OK, but then if the 10 dB difference doesn't have to be compensated for by us, then why do all those people feel that the DVD-A/SACD sub output from the 45a, 47ai, 2900 is too low? The only conclusion I can draw here, is that at least on the 45a and 47ai, we all do know that the sub test tone is too low anyway. On the 2900 too (in a specific mode) maybe?

Yes that's exactly right!
The test tone[for the sub] is screwed on the 2900 as well,Denon Jeff has "confirmed" this indirectly when he said that the BM was modeled after Dolby's BM structure,which requires the built in test tones to have the lowered level in the LFE levels[decoder boost]which is completely wrong for DVD-A and SACD.I'm also not confident of the current crop of tones for HI-Res formats based on my experience with the afore mentioned Telarc disc tones [DVD-A}.

 

[Steve_AS]

Question: is it reasonable to assume that these DV-45a speaker size settings would be the maximum/minimum 'bookends' for a range of subwoofer output levels (Front/Ctr/Surround) from the same recording?

MAX: small/small/small
MIN: large/large/large


I ask because I've been using a RatShack SPL meter to compare sub outupt levels at different speaker size settings (all else same) -- and the results are, to say the least, counterintuitive. I'm totally confused at this point as to what the DV-45a is actually doing to .1 and summed bass material. (and I have a email in to Chesky to figure out what's going with *their* .1 test tone, which seems to be another matter entirely). Here's a sample of some of my measurements, using the third bass note of 'Gaslighting Abby' from teh DVD-A layer of 'Two Against Nature', with the DV-45a set to 5.1 audio output, and the meter centered on 80 dB, pointed at the subwoofer cone from about 2.5 ft away. Analog output from the 45a sub channel is connected directly to the sub. C.U.T. = channel under test. I have sorted the results from loudest to softest. (Also,I'd be interested to know if there are any discs with DVD-A .1 test tones out there, *other* than the Chesky disc.)


Fr CtrSur SubC.U.T.output?dB
SSSONSUByes+1.75LOUDEST
LLLONSUByes+1.25
LSSONSUByes+1
LLSONSUByes-0.25
SSOFFONSUByes-0.75
LOFFLONSUByes-1.25
LLOFFONSUByes-1.5
LOFFSONSUByes-1.5
SOFFOFFONSUByes-1.5
SOFFSONSUByes-1.5
LOFFOFFONSUByes-3
LSLONSUByes-3
LSOFFONSUByes-4SOFTEST

 

[Brian L]

Steve,

Good to see you are still on the case!

As for other DVD-A tones, Telarc has them on some discs (Tribute to Weather report for example). I have not gone back to text those against the Chesky tones.

I have not analyzed your data, but in general, I guess I can believe that the sub output could change depending on the BM settings, because the bass frequencies would be divided between the sub and mains under some circumstances. Of course, that would depend on the crossover (100 Hz in the 45A, slope, and the composition of the test tones).

I am going to be on the road for a bit, and may not have access to the HTF, but I sure do want to see how this all shakes out.

BGL

 

[Steve_AS]

Thanks Brian, I'll pick up the Telarc WR disc and see how *it* behaves.

I've also done a series of measurements of what happens to the Front left channel when at various sub woofer ans speakers size settings. The results are also confusing. It appears at first pass that the DV-45 does *not* reroute .1 info to other channels, when the sub is OFF. I'll be verifying these results and posting everything within the next week or two.

 

[Brian L]

Another option for testing would be to measure the output of the various channels (the sub in particular) with a multimeter. I actually did that on advice from Pioneer when I first noted that the LFE channel was low compared to the others.

It is easy to do (assuming you have a multimeter handy). Just set it for AC Volts, fire up the appropriate test tones, and touch your probes across the output jack (It is easier if you insert an RCA cable, and measure the opposite end; that way you are connecting to the male RCA, not the female.

The beauty of that method is that it takes EVERYTHING out of the signal path other than the 45A.

BTW, when I did those tests, it correlated exactly with what my SPL meter and what my ears were telling me; the LFE/Sub channel was low. I do not recall the exact numbers, but it was substantial when comparing the sub channel with any of the main channels.

BGL

 

[Jeff O.]

Steve,
Just to clarify. When you made the above measurements were your other speakers on or off?
Jeff

 

[Steve_AS]

Steve,
Just to clarify. When you made the above measurements were your other speakers on or off?
Jeff

The other speakers were effectively OFF , because the receiver was bypassed completely. Hookup was direct from the sub output of the DV-45a to the RCA jacks of the (Velodyne) subwoofer.

I'd like to report another quirk of the DV-45a if I might, that I'm not sure I reported before. Namely: when the audio output option of the player is set to '5.1 channel', the speaker installation (speaker size) settings *also* apply to the dedicated 2-channel analog output! This is nonsensical from a design perspective, but true; I verified it by playing a 50 Hz tone from the Stereophile Test CD. With DV-45a audio output set to '5.1', and mains set to LARGE I calibrated the tone to the 0 dB setpoint of an SPL meter touching a front speaker grill at woofer midpoint. The reading was much reduced (at least -10dB) below 0 dB when the speakers were set to SMALL.

If the audio output was set to '2 channel', then the readings for LARGE and SMALL front were both the same; however, both were >+6dB louder than the calibration condition.

Proper design, IMO, would always have full-range signal emitted from the dedicated stereo analog ('CD') outputs. The player would ignore its 'audio output', speaker size, delay, and level settings when using these outputs. But that ain't so, for the DV-45a.



.

 

[Phil_DC]

Steve_AS,

Running those tests was a great idea and has given me a great idea.

I think if I have time this weekend I will run similar tests using my 47Ai with and without my M&K BMC bass controller. That way I can see what effects external bass management actually has on the bass output.

Maybe someone here with a Outlaw ICBM can do the same thing and we can compare output effects of the two bass management controllers as well.

I would be very curious to see how the BMC stacks up against the ICMB and this would help others decide if getting a bass management controller is worth it.

 

[Brian L]

With DV-45a audio output set to '5.1', and mains set to LARGE I calibrated the tone to the 0 dB setpoint of an SPL meter touching a front speaker grill at woofer midpoint. The reading was much reduced (at least -10dB) below 0 dB when the speakers were set to SMALL.

Every day, I kneel towards the Oulaw's hide and chant, Thank for my ICBM, Thank you for my ICBM, Thank you for my ICBM.......

BGL

 

[Brian L]

With DV-45a audio output set to '5.1', and mains set to LARGE I calibrated the tone to the 0 dB setpoint of an SPL meter touching a front speaker grill at woofer midpoint. The reading was much reduced (at least -10dB) below 0 dB when the speakers were set to SMALL.

Every day, I kneel towards the Outlaw's hideout and chant, Thank for my ICBM, That you for my ICBM, That you for my ICBM.......

BGL

 

[Steve_AS]

Every day, I kneel towards the Outlaw's hideout and chant, Thank for my ICBM, That you for my ICBM, That you for my ICBM.......

BGL

I thank whoever included digital outputs and inputs on my DV-45a and HK AVR520. The stereo CD playback issue thereby becomes a non-issue. (And it's probably why it took me so long to check the analog CD output performance -- I';ve been doing nearly all my listening to CDs via the digital out.)

 

[Steve_AS]

(repost of something lost to the 'database problem')

Another option for testing would be to measure the output of the various channels (the sub in particular) with a multimeter. I actually did that on advice from Pioneer when I first noted that the LFE channel was low compared to the others.

It is easy to do (assuming you have a multimeter handy). Just set it for AC Volts, fire up the appropriate test tones, and touch your probes across the output jack (It is easier if you insert an RCA cable, and measure the opposite end; that way you are connecting to the male RCA, not the female.

I'd like to try this to try to get around frequency response differences in the sub (I do have ana analog multimeter) but I want to know *exactly* what you mean by touching the probes 'across the output jack' -- if, for example, I use the RCA cable method you mention, am I only touching the 'pin' , with one probe, or do I use both probes and touch one to the 'pin' and the other to the 'surround'?

I'd hate to short-circuit my player -- or myself