• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Ji-Ji-Ji-Jitter

ejr

Member
Joined
Jan 6, 2023
Messages
94
Likes
26
I've mentioned, in more than one thread, that I can hear something which I think is what others have called a digital "glare" (especially as it relates to DACs that use an ESS chip).
What I hear, specifically, is a little too much high frequency that appears to be added to, or over-emphasized in, the highs of any given track. I also notice that individual instruments seem to be more isolated than what you would hear if the same piece were recorded in a studio or hall where the sound of one instrument bleeds a bit into that of the others (especially those closest). I don't consider that latter "glare", but I do feel that allowing some of that bleed-through makes a recording feel less realistic to my ears.

I was also sometimes hearing a distortion in the loudest instruments (or those that have been bumped up to stand out in the mix, like dialog over the music in a movie soundtrack). The best way to describe it is that the sounds suddenly seem very low-fi (like an old transistor radio with a single speaker back in the 1960s cranked up too high, pushing out on top of everything else). That's what bugged me the most. Then, one day, I saw a DAC review where the reviewer advised that all DACs be set to the lowest DPLL value to "improve fidelity". I did so and the distortion becaome worse. So, I tried the opposite (setting it to the highest DPLL value on both my DACs) and that removed most of the disortion I was hearing.

Apparently the thing that most bothered me about my DACs (both of which are Loxjie products that use ESS chips) is the jitter. Removing as much of that as possible has had more effect than changing the filters or sound colors (and there seems to me much less difference between them now).
 
Apparently the thing that most bothered me about my DACs (both of which are Loxjie products that use ESS chips) is the jitter.

For your benefit ....


Jim
 
My imagination isn't that good. Raising the DPLL settings eliminated a nasty sound that has been occurring for a couple of years. Call it jitter or somerthing else. It worked. And it if doesn't apply to DACs, I don't know why a DPLL setting was included on my DACs
 
I've mentioned, in more than one thread, that I can hear something which I think is what others have called a digital "glare"...
Relax. You probably can't.
 
IME "jitter" is the answer a sufferer of audiophile digital neurosis almost invariably lands upon, at some point. Just the name itself seems to explain everything; it doesn't help that the audiophile press made a tremendous fuss about jitter some decades ago, which continues to reverberate through the hobby.

The OP would do best to provide measurement and blind test results. That would go furthest to find the true cause.
 
Or a better, more detailed explanation about what the DPLL setting is supposed to do. Since increasing it fixed whatever I have been hearing and complaining about for approximately two years, whatever it fixes must have been the cause.
 
Well, it's a big enough difference for me to notice and appreciate it.

1. Objectional sound in a piece of music, always in the same place.
2. Lower the DPLL setting to 0 and it gets worse.
3. Raise it to the max value and it goes away.

Works on both systems with the signal source coming through an ethernet cable on one (to the D40) and wi-fi on the other (to the D30).

I will test with the output from my CD player on the D30, using a disc where I have been hearing the same type of distorion. I will also test with the CD player's built-in DAC for comparison and post the results here.
 
Sure, but measurements would show what it does, if it does anything. And a blind test would show if it matters.
Well, it's a big enough difference for me to notice and appreciate it.

1. Objectional sound in a piece of music, always in the same place.
2. Lower the DPLL setting to 0 and it gets worse.
3. Raise it to the max value and it goes away.

Works on both systems with the signal source coming through an ethernet cable on one (to the D40) and wi-fi on the other (to the D30).

I will test with the output from my CD player on the D30, using a disc where I have been hearing the same type of distorion. I will also test with the CD player's built-in DAC for comparison and post the results here.
Do you notice the different approach @ejr ?
 
Or a better, more detailed explanation about what the DPLL setting is supposed to do. Since increasing it fixed whatever I have been hearing and complaining about for approximately two years, whatever it fixes must have been the cause.
Solution: Record the output of the DAC with different DPLL settings. (on an ADC / interface, not with a mic) Use the same music clip and/or test tones. If it's as easily audible as you say, then it will show up immediately when you compare the recordings using Deltawave. Then we can start hunting down the actual cause.

Garden variety jitter would not sound the way you're describing, I don't think - but that doesn't mean nothing could have possibly gone wrong with your DAC. Whatever the problem, it should be visible in comparisons and we can start hunting it down that way.
 
Last edited:
When the DAC uses WiFi or Ethernet input then the jitter on the data packages should have no impact since the DAC does not use the data instantly but stores it temporarily and then read out with the clock signal of the internal clock oscillator. Reason for this because both Wifi and Ethernet send non-synchrnoized data and can have different timespan between sent packages. If DPLL has an effect then I estimate it is DAC internal and may be a unresolved problem with the circuit design.
 
Well, it's a big enough difference for me to notice and appreciate it.

1. Objectional sound in a piece of music, always in the same place.
2. Lower the DPLL setting to 0 and it gets worse.
3. Raise it to the max value and it goes away.

Works on both systems with the signal source coming through an ethernet cable on one (to the D40) and wi-fi on the other (to the D30).

I will test with the output from my CD player on the D30, using a disc where I have been hearing the same type of distorion. I will also test with the CD player's built-in DAC for comparison and post the results here.
Lower DPLL would be better if it's jitter or skipping, 5 is default. Going to max value fixes it? There are problems with optical in, if that's what you’re using, dealing with some televisions and ESS dacs. Not sure if it has anything to do with what you’re experiencing. Here's a link about it.

Post in thread 'Topping E70 Stereo DAC Review' https://audiosciencereview.com/foru...ping-e70-stereo-dac-review.39188/post-1425202

EDIT: Sorry you have Loxjie not Topping. NEVER MIND.
 
Okay, here's what I did:

1. First of all, I noticed what JustJones said above when I went to change the DPLL setting to zero. It actually says on the Loxjie D30 menu that lowering the value lowers jitter. So, I guess, what I have been doing is raising the jitter (or the setting that is supposed to address it) rather than lowering it (unless Loxjie implemented this feature backwards!)

2. Next, I listened to about 5 minutes each of the first and second movements of Beethoven's 9th symphony on my Denon 600NE CD player: first with the DPLL setting on the D30 at zero (minimum or no jitter), then with the DPLL setting on Maximum. There was less distortion on both than with the Wi-fi signal streaming from Amazon music -- but, that said, the Maximum setting was better. Setting it to zero made it sound a bit muddy -- not to the point of distortion (which is what the streaming signal sounded like to me) -- but enough to make me prefer to listen to it at Maximum. It sounded a bit smoother, too (if I can use that word without setting off an argument).

3. Then, I listened to the same selections, using the built-in DAC on the CD player. It was very hard to distinguish between the output of the D30 with the DPLL value at Maximum from the Denon DAC when I flipped between them. I couldn't say whether I liked one better than the other. IMHO the Denon DAC does well with recordings like this (symphonic, where all the instruments are in one big studio or hall and tend to blend together) and less well with contemporary music or jazz combos with fewer instruments, recorded track by track, with potentially a lot of separation between them.

Which brings me back to a post that I made earlier, to the effect that a wider variety of music should be used to evaluate DACs and other audiophile equipment. Specifically, I feel that classical and contemporary music scored for symphonic instruments is under-represented (perhaps because they are harder to record or render?) I mean, really, distortion and noise are often used intentionally in a lot of genres and it seems to me that some tracks would sound just as good regardless of the hardware and settings used to reproduce them.
 
Last edited:
And it if doesn't apply to DACs, I don't know why a DPLL setting was included on my DACs
AFAIK it applies to SPDIF input.
There are problems with optical in, if that's what you’re using,
The post you replied to says ethernet and wifi :) : "the signal source coming through an ethernet cable on one (to the D40) and wi-fi on the other (to the D30)."
 
The mapping of DPLL bandwidth to DAC settings seems to vary. I have definitely seen DAC manuals indicating higher setting = higher bandwidth, which would mean you would have to increase it to cope with problematic SPDIF outputs. So if in doubt, RTFM.

One would think that there should be some easy way to identify period dropouts. Perhaps a low-frequency (<100 Hz) sine?
 
Back
Top Bottom