MiniDSP SHD vs Pioner VSX-LX505 : noticeable difference in sound quality

[pkane]

@pkane
DeltaWave takes care of level errors and this seems reasonably close. So if he heard a difference, but it didn’t have a difference on DeltaWave, you could say it was just the level. Since DeltaWave is showing a difference what needs to be done is to show that comparing the same setup twice also nulls deeply.

Using a microphone has more noise so it should be harder to show a difference as long as your negative controls are good.

But moving the microphone is bad…

DeltaWave can automatically adjust for level differences between the two captures. There's no point in discussing audible differences if a proper level matching procedure can completely eliminate them.

But, in this case, the level matching was done, but it still shows significant differences in the frequency response. I wouldn't be surprised if some sort of room correction/DSP was active for one or both. Here's the difference in frequency response between the two:

Note the nearly 20dB difference around 3.5kHz, a frequency range where the ear is most sensitive.

 

[peng]

I'm not sure what the point is there. They ARE different AND measure different AND sound different. What's the problem?

Whether they should or should not measure differently is another matter. Going by Amir's measurements I'd expect the difference between them to be small, but it appears that's not the case. My money is on an unknown difference in the settings and processing, but it could simply be load sensitivity.

Maybe we need more measurements, 97 dB SINAD at 2 V, 1kHz test signal is not enough. I would like to see at the minimum, some SINAD vs level vs frequencies, such as what Amir did on other AVRs and AVPs. That's if the goal is to try and determine the causes of the audible differences. Otherwise, as you alluded to, they sounded and measured different, so, imo it should be expected.

 

[welwynnick]

I'm rather mindful that you, me and everyone else here keeps wanting to add more and more tests to Amir's work.
Yes, 1kHz distortion isn't as revealing as distortion vs frequency.
Although Amir does FR vs load and max power vs load (R,C,L) I'd love to see distortion vs load as well.

Edit: It would seem fair to lift some of the burden, and skip the tests like FR that are usually good. Having said that, FR vs load does show up some switching amps.

 

[peng]

Everybody bends over backwards, leaving absolutely no stone unturned, to find evidence that all audio electronics sound the same.

The simple answer could be that the MiniDSP sounds better.

If curiosity demands, you could test again with the Pioneer playing 1 dB louder. Whenever I've done this, it never made any difference.

Nick

Why keep saying "everbody", and "all" audio electronics?

I thought only a few, once in the blue moon post such opinions that "all audio electronics sound the same", in such kind of blanket statements. Most people would qualify their claims with conditions. I would think that most asr members know better not to generalize too much.

 

[Sokel]

I'm rather mindful that you, me and everyone else here keeps wanting to add more and more tests to Amir's work.
Yes, 1kHz distortion isn't as revealing as distortion vs frequency.
Although Amir does FR vs load and max power vs load (R,C,L) I'd love to see distortion vs load as well.

Here the differences are huge,there's surely something going on other than the raw performance of the devices.
Have a look at the aligned spectrum,apart from the highs,the 110-150Hz area has a huge spike.

 

[peng]

I'm rather mindful that you, me and everyone else here keeps wanting to add more and more tests to Amir's work.
Yes, 1kHz distortion isn't as revealing as distortion vs frequency.
Although Amir does FR vs load and max power vs load (R,C,L) I'd love to see distortion vs load as well.

I could be wrong, but I thought Amir did include frequency dependence tests on his own, often enough.

 

[welwynnick]

Why keep saying "everbody", and "all" audio electronics?

I thought only a few, once in the blue moon post such opinions that "all audio electronics sound the same", in such kind of blanket statements. Most people would qualify their claims with conditions. I would think that most asr members know better not to generalize too much.

It was because the immediate attitude to a positive DBT was that the test MUST somehow be flawed, rather than legitimate.

 

[voodooless]

It was because the immediate attitude to a positive DBT was that the test MUST somehow be flawed, rather than legitimate.

Well… wasn’t it?

 

[GXAlan]

DeltaWave can automatically adjust for level differences between the two captures. There's no point in discussing audible differences if a proper level matching procedure can completely eliminate them.

Great. I think the ability to match levels is tough since many preamp/integrated amplifiers have 0.5 dB resolution for the volume *and* you can imagine that if an amplifier has load dependent FR changes, then matching to a 1 kHz test tone or matching to pink noise is still dependent on matching volume that isn’t matched across the whole chain so even correcting the source file digitally may not work. I like the idea of making the worse product louder for a sensitivity test but DeltaWave’s correction is key.

I wouldn't be surprised if some sort of room correction/DSP was active for one or both..

Looking at the original post, it’s going through the TV and then TV optical out. I bet the TV is doing something to the audio!

 

[MaxwellsEq]

It was because the immediate attitude to a positive DBT was that the test MUST somehow be flawed, rather than legitimate.

Lots of experience of measuring kit makes quite a lot of engineers suspect any test where there are significant differences between two level-matched devices performing the same task within their design limits. The deltawave results confirm that more digging is needed.

 

[JustJones]

Reading through the manual on the Pioneer it looks like the only way to bypass ALL DSP is going "Analog in Pure Direct" which is called Analog direct.
Perhaps Pure Direct using digital in still does some processing?

You can select a variety of listening modes according to the audio format of the signal to be input.
• The Stereo mode can be selected with any audio format.
• When analog signals are being input in the Pure Direct mode, the modes switches to the Analog Direct mode which passes signals directly to the amplifier without passing through the DSP (Digital Signal Processor).
• Listening modes available when headphones are connected are Pure Direct and Stereo only.

Of course I can be completely wrong and has nothing to do with it. This might only apply to the internal amps and not the pre outs.

The pre outs are 1v .

Rated RCA Output Level and Impedance
PRE OUT : 1 V/470 Ω
PRE OUT (ZONE 2) : 1 V/2.2 kΩ
LINE OUT (ZONE 2, ZONE B) : 200 mV/2.2 kΩ
LINE OUT (ZONE 3) : 200 mV/470 Ω

 

[Kachda]

The only wildcard is if the microphone is inaccurate. The way you prove this is not the case is to show that playing the same system twice generates much deeper nulls. So if A1 is like A2 and B1 is like B2 but A is very different than B, you are done.

Then you have proven, that two similarly measuring DACs that theoretically are transparent in a 1 kHz SINAD result in an audible difference at the speaker level.

The only reason I even bothered to take out the mic to record is that I could distinctly make out the difference in sound when using the minidsp vs avr. I just wanted to do an ABX test to confirm it's not my sighted bias creeping in. Though it's not a great recording, what you hear on the tracks is similar to what I am hearing in person, the minidsp being clearer and the avr sound comparatively muffled.

 

[Kachda]

The white one is "Recording" and the blue one is "Recording (2) "

Thanks. Recording is the minidsp, Recording (2) is the AVR. The AVR output seems to have significantly higher output in the 100-200hz region, which is what makes it sound muffled.

 

[Kachda]

Reading through the manual on the Pioneer it looks like the only way to bypass ALL DSP is going "Analog in Pure Direct" which is called Analog direct.
Perhaps Pure Direct using digital in still does some processing?


Of course I can be completely wrong and has nothing to do with it. This might only apply to the internal amps and not the pre outs.

The pre outs are 1v .

Thank you, I will try out "Analog in Pure Direct" and see if the results change. However, I am not sure if the subwoofer will get disabled in that mode, a 2ch signal may only produce 2ch output, not 2.1

 

[Kachda]

DeltaWave can automatically adjust for level differences between the two captures. There's no point in discussing audible differences if a proper level matching procedure can completely eliminate them.

But, in this case, the level matching was done, but it still shows significant differences in the frequency response. I wouldn't be surprised if some sort of room correction/DSP was active for one or both. Here's the difference in frequency response between the two:

View attachment 349225

Note the nearly 20dB difference around 3.5kHz, a frequency range where the ear is most sensitive.

Hmm. I have no idea why there would be such a big difference in the 3.5khz area. I am going to some more test of the AVR in Pure Direct vs 'Analog Pure Direct' modes to see if the AVR is doing some processing to mess up the sound.

@pkane - this is a great tool! is there a way to play the delta so I can hear the difference also ? probably may not make a lot of sense but just curious

 

[GXAlan]

The only reason I even bothered to take out the mic to record is that I could distinctly make out the difference in sound when using the minidsp vs avr. I just wanted to do an ABX test to confirm it's not my sighted bias creeping in. Though it's not a great recording, what you hear on the tracks is similar to what I am hearing in person, the minidsp being clearer and the avr sound comparatively muffled.

I am a proponent of using the mic for comparison in contrast to others. Your measurements gain even more validity if you can show that repeating measurements gets you a null or -50 dB or something instead.

Thank you, I will try out "Analog in Pure Direct" and see if the results change. However, I am not sure if the subwoofer will get disabled in that mode, a 2ch signal may only produce 2ch output, not 2.1

That’s right. It may be interesting to see because DeltaWave can tease out if the difference is only in the bass versus not.

 

[Kachda]

I am a proponent of using the mic for comparison in contrast to others. Your measurements gain even more validity if you can show that repeating measurements gets you a null or -50 dB or something instead.

Sure, I will repeat the measurements with the same 30s of music twice. Unfortunately the best mic I have is a UMIK-1. And to remove measurement error, I am going to use the same speaker (instead of next to each other), and setup the mic in a fixed position.

 

[Sokel]

is there a way to play the delta so I can hear the difference also ? probably may not make a lot of sense but just curious

Just press the green play button on the right side of the "match" .

 

[goat76]

Thanks. Recording is the minidsp, Recording (2) is the AVR. The AVR output seems to have significantly higher output in the 100-200hz region, which is what makes it sound muffled.

The level is way lower on "recording 2" (the AVR), to match the level to the recording of the miniDSP you must raise the level of "recording 2" by 1.9dB, which will get them to the same integrated LUFS level for your listening comparisons.

 

[peng]

Thank you, I will try out "Analog in Pure Direct" and see if the results change. However, I am not sure if the subwoofer will get disabled in that mode, a 2ch signal may only produce 2ch output, not 2.1

As GXAlan noted, you used two different signal paths with one goes through the TV and the other do not:

Setup was
Apple TV -> Pioneer -> TV -> TV Optical Out -> Minidsp SHD -> Hypex NC502MP Amp Channel 1 -> Speaker (Wharfedale Linton)
Apple TV -> Pioneer -> Pre Out -> Hypex NC502MP Channel 2 -> Speaker (Wharfedale Linton)

Could you reverse the two just to see if that would make a difference?