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Review and Measurements of JDS Labs EL DAC

solderdude

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#41
The scope plot makes sense to me... the stairsteps aren't there in reality in the recording. It is just the way they are displayed by the software that replaces sample points with lines by stairsteps as if they were reproduced by an R2R DAC without any post filtering.
There is no way such stairsteps would have been recorded this way with 192kHz (100kHz bandwidth)
Looks like an analysis problem to me where at some points the data did not get filtered properly.
 

March Audio

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#42
I my original post I just disagreed about what BE178 said and claimed that transients do have that high frequency components. I said nothing about whether or not they contribute to the sound.


Yes, that is the reason. Here is a zoom of the section of such a transient: View attachment 16522
Again, everyone could just download the demo version of RX7...

No, definitely not. I could tell about iZotope and their senior DSP developer behind all their algorithms. Or you could just as well watch their videos on YouTube and decide yourself.
Another zoomed view with combined spectrogram and waveform: View attachment 16519
These are no artifacts due to brickwall limiting, the levels are well below -9 dB or so.

As you all know, short transients contain high frequencies (see Fourier transform). And there is and was no general law prohibiting frequencies of transients far beyond 20 kHz.
I admit that I don't know much about analog tape recorders or microphones from 1976. Maybe an expert could help. I am just looking at the spectrogram.
However, as BE718 claims, maybe I just do not understand what I am looking at. Maybe he understands better.
You clearly do not have an understanding of what you are looking at. You are showing a signal that is stretching up to 90 KHz. What you are not doing is showing that it is genuinely a music signal. It is noise, distortion and spuria.

I suggest you do a search on the Internet and check how and where Hotel Califonia was recorded. None of the microphones or tape deck reached up to this bandwidth.

15 or 30 ips tape was typical of the era, so maybe 25, 35 KHz
 
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March Audio

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#43
I my original post I just disagreed about what BE178 said and claimed that transients do have that high frequency components. I said nothing about whether or not they contribute to the sound.


Yes, that is the reason. Here is a zoom of the section of such a transient: View attachment 16522
Again, everyone could just download the demo version of RX7...

No, definitely not. I could tell about iZotope and their senior DSP developer behind all their algorithms. Or you could just as well watch their videos on YouTube and decide yourself.
Let's correct you here, we were specifically talking about a drum hit. I made no such claim.

Your waveform there tells us little. What's the time base.
 
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March Audio

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#44
Here is another example where I do not understand what I am looking at.
Pink Floyd, Wish You Were Here, Immersion Set, 2011, Blu-ray disc, 24 bits, 96 kHz: View attachment 16521

Peak level of this section is -1.6 dB, no limiting or what so ever.
If you look precisely, you see transients go up to Nyquist.
This was recorded in 1975.
Judge for yourself.
I could show many other examples. I suggest (again) that people who question this just download RX7 and check their own high resolution files.
Now this looks more consistent with say 30 ips tape. However note how the signals up at the top end around 35 KHz are maybe 90 dB or more down.....so.even if you could hear that high frequency it would be inaudibly quiet.
 
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solderdude

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#45
No, it is a transient. I wrote this in the post. A transient is in fact a very important part of a sound. You should know this.
Leider nicht, Sie irren sich.
Es ist nur die weise worauf es sichtbar gemacht ist durch das Programm.
Das sind keine 'Transients'.
Im diesen fall sollte die frequenz davon etwas im MHz bereich sein.

Deutsch ist aber nicht mein eigenes Sprache.
 
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March Audio

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#46
No, it is a transient. I wrote this in the post. A transient is in fact a very important part of a sound. You should know this.

If you are so sure about that, why don't you just prove it?
It really isn't. It's obviously distortion and spuria for the reasons explained. The recording had no musical content at these frequencies. It simply couldn't, the mics and the tape just don't respond up to 90kHz. This is an artifact of some problem in the remastering process.
 
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March Audio

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#47
OK, this just takes too much of my time.
You can just ignore all what can be seen in the graphs. And you can ignore the correctness of RX or whatever.
I'm fine with it. And I'm out.
Good. If you are not prepared to take on board the technical knowledge that is held by members here then you are wasting peoples time. The explanations as to why you are incorrect are very simple and frankly obvious. If you choose dogma instead of learning that's up to you.
 
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amirm

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Thread Starter #48
Just to be precise, you are using Windows 10 Pro 64-bit build 1803, and if ASIO4ALL uses usbaudio2.sys it may truncate?
Not in front of my desktop but same problem happened on my laptop which is running build 1803. I don't know which DLL ASIO4ALL uses. I just know that I tested it without installing drivers and it truncated. I installed drivers and then it didn't.
 
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amirm

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Thread Starter #49
I think you misunderstand me. Maybe my English is not good enough, I don't know. I would like to clarify this.
Your English is perfect and I did understand your point. :)

With harmonic distortion, it is an industry standard measurement of good engineering. Manufacturers also spec their own so it is important that we try to confirm.

I don't know of phase distortion being an example of bad engineering. A lot of things create phase delays. Or phase distortion even if they are well engineered.

On audibility, gross amounts of phase distortion seems to be inaudible. Gross amounts of THD most definitely is audible.

Ultimately the point is this: my goal in reviews and measurements is to provide the least amount of data that accurately represents the level of engineering of a product. These graphs have a way of confusing people or causing them to lose interest. I know I hate reading long series of graphs others post.

I know some of you are diehard measurement readers and want more and more. :) But that is not what I like to get done here. There is so much gear to be reviewed that I need to spend my time doing that, than exhaustively measure one thing.

Now, if there is occasional interest in other measurements, as I have shown, I am happy to do it. I just don't want to create a dozen or more graphs for each review when less would do as far as the net message.
 
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#50
Hi Amir,

I'm new to ASR. Was planning on upgrading my Schiit Stack 2 to other Schiit products. Luckily i discovered ASR !!!

Between the EL DAC and the Topping D50, which one is better or sounds better ? I mostly use USB.

Thanks !
 
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amirm

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Thread Starter #51
Hi there. Welcome to the forum. I don't think you will hear the difference between them. I like the front panel display and volume control on Topping D50 so if it were me, I would get that one.
 
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#52
Hi there. Welcome to the forum. I don't think you will hear the difference between them. I like the front panel display and volume control on Topping D50 so if it were me, I would get that one.
Hi Amir ,

Thanks for the reply :) I have some newbie questions ...
- Am I right to say the Topping D50 will sound much better than the Schiit Modi2 ?
- Which one would make the biggest improvement , upgrading the headphone amp first or upgrading the dac first ? Currently I'm using Modi2/ Magni2/ HD6XX. Will upgrade the dac and amp one at a time.

Thanks for your patience.

Rgds,
Ben
 

Memoryerror

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#53
Your English is perfect and I did understand your point. :)

With harmonic distortion, it is an industry standard measurement of good engineering. Manufacturers also spec their own so it is important that we try to confirm.

I don't know of phase distortion being an example of bad engineering. A lot of things create phase delays. Or phase distortion even if they are well engineered.

On audibility, gross amounts of phase distortion seems to be inaudible. Gross amounts of THD most definitely is audible.

Ultimately the point is this: my goal in reviews and measurements is to provide the least amount of data that accurately represents the level of engineering of a product. These graphs have a way of confusing people or causing them to lose interest. I know I hate reading long series of graphs others post.

I know some of you are diehard measurement readers and want more and more. :) But that is not what I like to get done here. There is so much gear to be reviewed that I need to spend my time doing that, than exhaustively measure one thing.

Now, if there is occasional interest in other measurements, as I have shown, I am happy to do it. I just don't want to create a dozen or more graphs for each review when less would do as far as the net message.
Maybe just more on the devices that do really, really well.
 
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amirm

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Thread Starter #54
Hi Amir ,

Thanks for the reply :) I have some newbie questions ...
- Am I right to say the Topping D50 will sound much better than the Schiit Modi2 ?
- Which one would make the biggest improvement , upgrading the headphone amp first or upgrading the dac first ? Currently I'm using Modi2/ Magni2/ HD6XX. Will upgrade the dac and amp one at a time.
Hi Ben. Differences in DACs may be very hard to hear. In the case of Modi 2 though, its output is low so you may hear other DACs sounding better because of that.

Answering your larger question, unless you are hearing buzz, hiss, computer activity through your DAC, I would put the money toward amplifier.
 
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#55
Hi Ben. Differences in DACs may be very hard to hear. In the case of Modi 2 though, its output is low so you may hear other DACs sounding better because of that.

Answering your larger question, unless you are hearing buzz, hiss, computer activity through your DAC, I would put the money toward amplifier.
Hi Amir,
To me the Modi2/Magni2 sound dull w/ HD6xx. I don't why... maybe the Magni2 cant drive the HD6xx properly.
Anyways I will go upgrade the amp first then.

Thank you so much for your input.
Ben
 
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amirm

amirm

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Thread Starter #56
To me the Modi2/Magni2 sound dull w/ HD6xx. I don't why... maybe the Magni2 cant drive the HD6xx properly.
I like to have a very powerful amplifier for HD-650. The impedance is high and most amps have too little power with that kind of load. That may be what you are hearing.
 
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#57
I like to have a very powerful amplifier for HD-650. The impedance is high and most amps have too little power with that kind of load. That may be what you are hearing.
Hi Amir,

In your opinion, when looking for an amp that would drive the HD6xx / 650 properly, what is the ideal output @300 ohms should I look out for in the amp specs.

As always thanks ...
Rgds,
Ben
 
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amirm

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Thread Starter #58
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