I guess the limitation is the two power supply converters that generate +/-12v from a single 9v. even though you have an external linear PS, these converters seems to be based on smps.
best way is to have an additional separate dual rail linear PS for the opamp.
That's fine - the power supply splitting and going linear - but the question is will this alter the problems that I found with the unit? The HF "tzzzing" and the soundstage flattening??
And, has the HF "bump" been measured?
I suspect that it is not measurable, since that would show up in a rudimentary frequency response check, and the mfr would see that and it would not meet the distortion spec!
And, has the HF "bump" been measured?
I suspect that it is not measurable, since that would show up in a rudimentary frequency response check, and the mfr would see that and it would not meet the distortion spec!
Same here, hickup's using either of my two AirPort Expresses (new & old model), where as digital out from my retina works, so does usb.
I got it off Amazon, I'll be sending it back, and look for something else ...
hmmmm... lack of lock, not good.
will it lock without the DEQ interposed??
ran it briefly off 9v batts, with CDs, sounded better to a degree.
will have to listen more and also try off the USB port next.
_-_-
will it lock without the DEQ interposed??
ran it briefly off 9v batts, with CDs, sounded better to a degree.
will have to listen more and also try off the USB port next.
_-_-
Hi bear
I have the same problem with or with or without the DEQ in between. It happens with two version of airport express. no problem with all other sources including a Quad cdp, an usb to spdif box based on cm6631a and a PS Audio Lambda. There may be some compatibility issue with the airport express signal. The airport express output is optical therefore it's not a problem related to impedance matching.
I have the same problem with or with or without the DEQ in between. It happens with two version of airport express. no problem with all other sources including a Quad cdp, an usb to spdif box based on cm6631a and a PS Audio Lambda. There may be some compatibility issue with the airport express signal. The airport express output is optical therefore it's not a problem related to impedance matching.
Hi Quantran,
Ok, if you also have the problem then I am starting to think it's a generel problem which can't be fixed. I'll return it, and start looking for something else.
Thanks.
That means I am using a digital equalizer Behringer DEQ2496 between the airport express and the DAC.
Ahh, got it. Sadly that makes the project a bit too expensive. I'll return the M8, and then possibly get an irDac instead.
Thanks.
The DEQ is for for room correction only. I think you may not need it if your listening room is ok. I need this DEQ for any DAC due to a problem with room resonance.
Have you tried the M8 with other sources?
Have you tried the M8 with other sources?
Hi Quantran,
Got it, yes via USB from my two Macbooks, and spdif from my Macbook Retina (I find the S/PDIF better). It "only" fails with Apple Express using spdif.
I'm returning for this reason, as I use airplay to listen to streaming sources (radio).
Cheers,
Impressions
After a few auditions...
Generally speaking there is something good and something not so good.
The good is that it seems to be strangely clean in terms of sibilence.
The bad is that it seems on all filter settings to be somewhat "zingy".
Cymbals all tend to sound the same.
The sibilence seems driven up in frequency and I'm guessing now resides up above 7-9kHz. Both the cymbals and the sibilence seem to reside in the same general area sonically, and all have the same "zingy" character.
Bass and midbass seem shy.
The filters seem to move the soundfield from pretty compressed and flattened ("slow") to about right ("mini") to rather dynamic but way too "zingy" in (fast).
No doubt that the wallwart supply makes the "zing" worse.
Running off a lowly 9v battery improves the overall sound.
Thinking maybe if one could bypass the internal supply parts, think there may be one or more smps type thingies to make different voltages, and maybe swap out the opamps the thing might fly right.
But, I'm not looking for a project, unless the results are positively dramatic, stunning and change the character of the SMSL M8 rather significantly for the better.
Oh, I did not check with hi-res files, only SPDIF from a transport. The entire presentation might be different with USB input and hi-res files. Probably something to check, for reference. However for now the ability to present CD in a very good way is very important.
For reference, the system is Quad57 ESLs, BEAR Labs DC Coupled SE Mosfet amps, passive discrete stepped "L" attenuators, DAC. Very minimalist.
The effect(s) of the filters are quite interesting...
_-_-
For reference, I am comparing to a very good custom PCM63 DAC... (and other listening experiences)
After a few auditions...
Generally speaking there is something good and something not so good.
The good is that it seems to be strangely clean in terms of sibilence.
The bad is that it seems on all filter settings to be somewhat "zingy".
Cymbals all tend to sound the same.
The sibilence seems driven up in frequency and I'm guessing now resides up above 7-9kHz. Both the cymbals and the sibilence seem to reside in the same general area sonically, and all have the same "zingy" character.
Bass and midbass seem shy.
The filters seem to move the soundfield from pretty compressed and flattened ("slow") to about right ("mini") to rather dynamic but way too "zingy" in (fast).
No doubt that the wallwart supply makes the "zing" worse.
Running off a lowly 9v battery improves the overall sound.
Thinking maybe if one could bypass the internal supply parts, think there may be one or more smps type thingies to make different voltages, and maybe swap out the opamps the thing might fly right.
But, I'm not looking for a project, unless the results are positively dramatic, stunning and change the character of the SMSL M8 rather significantly for the better.
Oh, I did not check with hi-res files, only SPDIF from a transport. The entire presentation might be different with USB input and hi-res files. Probably something to check, for reference. However for now the ability to present CD in a very good way is very important.
For reference, the system is Quad57 ESLs, BEAR Labs DC Coupled SE Mosfet amps, passive discrete stepped "L" attenuators, DAC. Very minimalist.
The effect(s) of the filters are quite interesting...
_-_-
For reference, I am comparing to a very good custom PCM63 DAC... (and other listening experiences)
I don't like the fast and slow filters. Mini filter sounds more natural to me. The opamps seem to be the type recommended by many people, opa1612, if I remember corectly.
I think the sound is ok or even good value for money with good power supply but we can expect it to sound as good as a dac costing a thousand dollars or more.
I think the sound is ok or even good value for money with good power supply but we can expect it to sound as good as a dac costing a thousand dollars or more.
Just reporting my observations.
Yes the mini filter is the best compromise...
...I was thinking that passing the output through the right transformer might have a beneficial result... just an idea.
Given the $250 price I had hoped for more of what I personally wanted.
I'm going to be trying out a range of options WRT the various current DAC chips, and different boards to see what sort of performance and results they give...so...
If anyone is interested, this one can be had at a price under the retail, PM me.
Yes the mini filter is the best compromise...
...I was thinking that passing the output through the right transformer might have a beneficial result... just an idea.
Given the $250 price I had hoped for more of what I personally wanted.
I'm going to be trying out a range of options WRT the various current DAC chips, and different boards to see what sort of performance and results they give...so...
If anyone is interested, this one can be had at a price under the retail, PM me.
Hi bear
Transformer ouput stage is very good for Vout DAC such as AK439x, AK449s, CS4397/8, etc. An AK4396 with transformer output is my reference DAC right now. It easily outperforms the NAD M51 DAC retailed for $2K. Of course some efforts are required to make a proper power supply and some solution for jitter reduction. The total cost for me is very low.
There is very little public information about the ESS DAC but I understand that it is a current output chip which is more difficult to use a transformer output stage.
Transformer ouput stage is very good for Vout DAC such as AK439x, AK449s, CS4397/8, etc. An AK4396 with transformer output is my reference DAC right now. It easily outperforms the NAD M51 DAC retailed for $2K. Of course some efforts are required to make a proper power supply and some solution for jitter reduction. The total cost for me is very low.
There is very little public information about the ESS DAC but I understand that it is a current output chip which is more difficult to use a transformer output stage.
Seems to be a characteristic of the ESS DAC chip itself. The noise modulation in the HF region I also get with my smartphone (Meizu MX4 pro) which has the ES9018K2M. It also renders massed violins poorly, presumably the same noise modulation is occurring there.
Interesting...
...oddly the unit sounded better yesterday with a very good quality variable regulated supply running it, over the battery that I tried second after the stock wall wart. Still not quite right, but at the moment, unless it is a mirage, sounding more reasonable by far.
Maybe it actually changes with "break-in"... we'll run it some more and see what happens next.
...oddly the unit sounded better yesterday with a very good quality variable regulated supply running it, over the battery that I tried second after the stock wall wart. Still not quite right, but at the moment, unless it is a mirage, sounding more reasonable by far.
Maybe it actually changes with "break-in"... we'll run it some more and see what happens next.
Yes, I found the sound to be very clean with my diy power supply but it's strange that the top end is a bit emphasized. The emphasized frequency is very high up so I don't feel fatigue but it's just a bit not natural if I listen to acoustic music.
Don't think it is so high up, maybe 8-10kHz.
It is almost like the "de-emphasis" curve (that is not often used in CD playback) is supposed to be on, but is off!
of course this is not possible, but it is sort of that type of sound...
I need to set the unit up for USB input and then find a way to run a sweep from software or a wav file and see if it actually measures flat...
_-_-
It is almost like the "de-emphasis" curve (that is not often used in CD playback) is supposed to be on, but is off!
of course this is not possible, but it is sort of that type of sound...
I need to set the unit up for USB input and then find a way to run a sweep from software or a wav file and see if it actually measures flat...
_-_-
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