What's the value of desktop DACs?

[maximum3535]

So as far as I understand it, desktop class amps are useful because the extra headroom allows for better bass response, since bass levels in recordings needs to be elevated to match audible levels compared to other frequencies.

However, I'm trying to figure out the value of desktop DACs. If the tanchjim space measures 115 SINAD, and let's assume that cleaner, better measuring sound is what we're after, and that we're satisfied with 115 SINAD and how all the other DAC-related measurements stack up for the tanchjim space, is there additional value to desktop DACs at all in terms of sound quality?

I'm also wondering what volume level to set my dongle DAC when connecting it to an amp. I read somewhere (https://www.head-fi.org/threads/using-dongle-as-dac-for-external-amp.938411/) that it's optimal to set it at max volume or close to max. However, I was wondering, if at max volume for the dongle DAC there's less headroom, wouldn't bass response fed into the amp be reduced? I've tried to wrap my head around resistances, voltages, power, etc. but I can't make sense of it.

 

[staticV3]

I read somewhere (https://www.head-fi.org/threads/using-dongle-as-dac-for-external-amp.938411/) that it's optimal to set it at max volume or close to max. However, I was wondering, if at max volume for the dongle DAC there's less headroom, wouldn't bass response fed into the amp be reduced?

Definitely not.
With an external Amplifier as load, dongles will be able to produce all frequencies faithfully, even with the volume set to 100%.

 

[DWPress]

One consideration is that quite a few DACs meant for portable use do not put out a full 2 volts for line level connections. Many amps will perform best, and utilize their full volume potential, if they are presented with 2V for single ended and 4V for balanced connections. Quite a few of the dongles I've seen reviewed here are around 1V which is perfectly adequate for headphone use.

Your dongle of choice spec sheet should give the information.

Edit: I just looked it up and the tanchjim space has a few options for output voltage (a lower outputV can give better test results esp in SINAD) but it will do both 1V low 2V high for RCA or 2V low 4V high for XLR. Everything you need it to do and you won't be missing anything that's happening on the recording or potential SPL.

 

[OldTimer]

The only reason is the desktop looks big and feel nice on the table than the small portable and not seen from far. So, it’s only looks and feels.

 

[ZolaIII]

Their own clean power source as one of the advantages. More input types including fiber optical Toslink securing no interface or ground loops leeks in from noisy sources such as PC (sometimes even without power input from USB audio connection). Seriously we lack on front of multichannel stand alone DAC's and DAC's with embedded DSP's a lot as it is on the market. There are such interfaces but most folks don't need high grade DAC's and mic preamplifiers which come with such and have to pay for it and even that is limited to balance one's only.

 

[Palladium]

I tried the Apple 3.5mm dongle once from my Win10 PC to LSR305s and they sounded anemic. So you really want a DAC at least 2V line-out to high impedance inputs like speaker amps or active monitors.

 

[staticV3]

I tried the Apple 3.5mm dongle once from my Win10 PC to LSR305s and they sounded anemic. So you really want a DAC at least 2V line-out to high impedance inputs like speaker amps or active monitors.

The LSR305 puts out 92dB SPL at 1m, with 0.25Vrms input:


If it sounds anemic using the Apple dongle, then that's a setup issue.

 

[Vamp898]

So as far as I understand it, desktop class amps are useful because the extra headroom allows for better bass response, since bass levels in recordings needs to be elevated to match audible levels compared to other frequencies.

That is when you do recordings, not when you playback! That is important to know.

Everything you say is correct when you're talking about a Sound Studio, recording Audio.

After the Recording/Mixing/Mastering is done, you don't need Headroom for the Bass response.

However, I'm trying to figure out the value of desktop DACs. If the tanchjim space measures 115 SINAD, and let's assume that cleaner, better measuring sound is what we're after, and that we're satisfied with 115 SINAD and how all the other DAC-related measurements stack up for the tanchjim space, is there additional value to desktop DACs at all in terms of sound quality?

I'm also wondering what volume level to set my dongle DAC when connecting it to an amp. I read somewhere (https://www.head-fi.org/threads/using-dongle-as-dac-for-external-amp.938411/) that it's optimal to set it at max volume or close to max. However, I was wondering, if at max volume for the dongle DAC there's less headroom, wouldn't bass response fed into the amp be reduced? I've tried to wrap my head around resistances, voltages, power, etc. but I can't make sense of it.

The reason to have a Desktop DAC is that you can connect it to an Desktop Amp.

The reason to have an Desktop Amp is when your Dongle doesn't get your Headphones loud enough.

The Tanchjim Space (as the Moondrop Dawn Pro) have 2*CS43131, that is only a DAC.

As this DAC has 2Vrms (with Balanced that means 4Vrms), Cirrus made 2 Versions of this DAC. An simple DAC that always outputs 2Vrms and expects you to connect it to an amp (CS43198) and an DAC that has an Volume Control and Impedance detection and stuff like that, so you can drive Headphones with it (CS43131) and it expects you to plug an Headhpone into it.

The Disadvantage of the CS43131 is, that it expects you to plug in a Headphone. You could just put it behind another amp but that is not an ideal scenario and not just a waste of energy (CS43131 consumes 40.2mW to produce 2Vrms while the CS43198 consumes 26mW) which automatically means it will produce much more heat but the output power of the CS43131 varies with the impedance you put behind it. Chances are there will be no issue, but its not ideal.

So use your Tanchjim Space or Moondrop DAWN PRO (its cheaper for the same sound quality, so rather buy that one) and use it, unless it doesn't get your headphones loud enough.

I tested the Moondrop DAWN PRO with 5kΩ (yes, that is 5.000 Ω) and the frequency response at 100% Volume High Gain was still perfectly flat (Even beyond 40kHz)

This here is the result when playing 30s of Hi-Res White Noise




So don't worry about the Bass, it sounds perfectly flat, even with very high loads (if you ever plan to buy an 5kΩ Headphone) at 100% Volume High Gain. You do _not_ need Headroom.