• 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!

Dragonfly Black not playing well with amp?

vert

Active Member
Forum Donor
Joined
May 30, 2018
Messages
284
Likes
256
Location
Switzerland
Hello,
A
friend recently gifted me some Stax Sigma headphones. It had been a long while since I hadn't used my stereo system, my habitual mode of music listening these days being off a Dragonfly Black hooked to an android phone running USB Audio Player.
So at first I installed the Stax adapter behind the amplifier, plugged in the phones and put on a CD. Both the amp, 35 W power, and the CD player are from Teac; a modest, but reasonable quality combo, the H300 model. The Stax held their promise, sounding just marvelous. Then I decided to try with the Dragonfly off my phone, plugged on the Aux input behind the amp. All the Stax magic evaporated - no more sparkle and dimensionality, only a flat, veiled and dull sound. What might have happened there? The Dragonfly is supposed to be able to work with some powered speakers or an amp. But here the difference with the Teac CD player as a source is almost like night and day. Moreover, the power off the DF was very weak; I could max out the amp and the volume would still be bearable. With the CD player as a source, halfway on the dial was plenty enough.

Could it be that the Dragonfly doesn't work that well in that configuration due to a case of "double amping" (the DF being a DAC/amp) and the Stax being what they are, mercilessly reveal every parasite noise? Occasionally I will hook it to my AV receiver (which is a lot more powerful than the Teac amp) and truth be told, the DF it will sound acceptable but nothing exceptional; I suspect an effect due to weak output on the DF's part here as well. Would running the DF off my computer give better results?

If it turns out the DF has that limitation I'll be "on the market" for a fixed DAC. I'm looking to spend as little as possible. Which values should I look at to know if output is going to be enough? I happened on this site through the Topping D30 article. Interesting but have they been changing some components? Would the D30 give me CD quality results? As I said, the sound off my CD player is really, really good and crystal-clear. Otherwise, have you guys heard about the company Audiophonics? They're a French distributor of Chinese electronics who also make some very affordable DACs under that name, Audiophonics. They have a good reputation but few online reviews. They're easily available from my country, Switzerland. That was a long first post with many questions and I thank you for your patience if you made it so far.

Best,
vert
 

Vincent Kars

Addicted to Fun and Learning
Technical Expert
Joined
Mar 1, 2016
Messages
781
Likes
1,555
Have you tried setting the volume control of the phone to max?
 

Blumlein 88

Grand Contributor
Forum Donor
Joined
Feb 23, 2016
Messages
20,523
Likes
37,056
The Dragonfly black according to stereophile testing only puts out just over 1 volt max. The Teac CD player probably puts out 2 volts or possibly more. What you are describing sounds like more than 1 volt vs 2 volts (a 6 db difference). I wonder if the gain thru the Aux input is the same as whatever input you have the CD player using?

BTW, louder, even just a little louder, always sounds like a jump in sound quality. Sounds like something much more than just a loudness difference.
 
OP
V

vert

Active Member
Forum Donor
Joined
May 30, 2018
Messages
284
Likes
256
Location
Switzerland
@Vincent Kars & Blumlein 88 - Thanks a lot. I tried Vincent's suggestion and was suprised to see that indeed, pushing the Android volume slider all the way up did make a difference in volume. Surprised because I had always assumed the Dragonfly entirely took over all sound duties from the phone once active. I didn't expect the Android's volume control could have any effect but it did. And it was a positive effect, pushing the volume up a few notches, with a perceived better sound quality (the latter might be just an impression related to the increase in volume though, as Blumlein 88 points out).
At max bearable volume, which was now at about 90 % of the amp's volume knob, there a little distortion from the DF/phone setup. Overall the Teac CD player was still better by a margin wide enough as to make listening to the Sigmas through the Dragonfly seem not worthwhile. Guess I'll be heading to the "DAC recommendations" section soon :) B88, thanks for the very useful information about voltages and dbs; I try to learn about this stuff but I'm basically technologically illiterate.
I've been thinking about something else, I rip my CDs in FLAC with DbPowerAmp with a (recommended in the software) compression ratio of 5, on a scale of 10, to facilitate storage on my smartphone. I wonder now if that might have an effect on sound quality? Mmh.

PS: in addition to the Aux input I did try the Tape1 input, with the same results. I'll try Tape2 and Phono out of curiosity.
 
Last edited:

RayDunzl

Grand Contributor
Central Scrutinizer
Joined
Mar 9, 2016
Messages
13,202
Likes
16,982
Location
Riverview FL
I've been thinking about something else, I rip my CDs in FLAC with DbPowerAmp with a (recommended in the software) compression ratio of 5, on a scale of 10, to facilitate storage on my smartphone. I wonder now if that might have an effect on sound quality? Mmh.

Compression level shouldn't make any difference at playback.

FLAC Faq:

Why do the encoder settings have a big effect on the encoding time but not the decoding time?

It's hard to explain without going into the codec design, but to oversimplify, the encoder is looking for functions that approximate the signal. Higher settings make the encoder search more to find better approximations. The functions are themselves encoded in the FLAC file. Decoding only requires computing the one chosen function, and the complexity of the function is very stable. This is by design, to make decoding easier, and is one of the things that makes FLAC easy to implement in hardware.
 
OP
V

vert

Active Member
Forum Donor
Joined
May 30, 2018
Messages
284
Likes
256
Location
Switzerland
Compression level shouldn't make any difference at playback.

FLAC Faq:

Why do the encoder settings have a big effect on the encoding time but not the decoding time?

It's hard to explain without going into the codec design, but to oversimplify, the encoder is looking for functions that approximate the signal. Higher settings make the encoder search more to find better approximations. The functions are themselves encoded in the FLAC file. Decoding only requires computing the one chosen function, and the complexity of the function is very stable. This is by design, to make decoding easier, and is one of the things that makes FLAC easy to implement in hardware.
Thanks! Great to know I don't have to re-rip everything!
 

Blumlein 88

Grand Contributor
Forum Donor
Joined
Feb 23, 2016
Messages
20,523
Likes
37,056
@Vincent Kars

PS: in addition to the Aux input I did try the Tape1 input, with the same results. I'll try Tape2 and Phono out of curiosity.

No, NO NO do not try the Phono input.

The phono input has 45 or 50 db of gain, and a volt or so from the Dragonfly could burn out that input. Phono is for signals from a turntable cartridge. It is looking for voltage levels of a few thousandths of a volt. So don't try that.
 

DonH56

Master Contributor
Technical Expert
Forum Donor
Joined
Mar 15, 2016
Messages
7,835
Likes
16,497
Location
Monument, CO
^^^ +1.

It would also add the RIAA EQ curve, rarely desirable for a line-level source...
 
OP
V

vert

Active Member
Forum Donor
Joined
May 30, 2018
Messages
284
Likes
256
Location
Switzerland
Again thanks for the great replies. And thanks for mentioning not to use the phono out before I could attempt it. It is clear now that leaving DAC quality aside, the DF Black's main issue was the output. It seems such a standard issue that it's a little disappointing Audioquest would not to mention that the Red's 2 v output of would make it more suitable than the Black for use with a conventional amp. Why not mention a simple thing like that? Why not say that the Black is likely to fall short in that configuration? Knowing this, I would have bought the Red instead, but there's no way that "discovery" is going to make me upgrade to the Red at this point.

I just read the very interesting findings with the UMC204HD Behringer unit. Unfortunately I would likely run into similar output issues with it. I will investigate if such output levels are standard on these types of devices or if other affodable interfaces have higher outputs. As I play guitar as a hobby and was looking into alternatives to digital recorders, that could be an interesting solution for me. In fact I've seen the idea mention a few times on music gear forums. I have to mention something though, once I contacted Audient about using one of their interfaces as a DAC, and they replied in very clear terms that they did not recommend it - because, I suppose, they don't want to go out on a limb as their devices are not developed and tested specifically for use as DACs?

I'm giving myself a few more weeks to make a decision. Other than that I've registered on Massdrop in case an interesting sale pops up. Or I might go with this DAC:
https://www.audiophonics.fr/fr/dac-...-384khz-asynchrone-usb-xmos-noir-p-11961.html
Assembled in France. The assembly looks very clean. 15-day return policy. Very courteous and competent replies from their customer service. Few reviews but all excellent.
 

Blumlein 88

Grand Contributor
Forum Donor
Joined
Feb 23, 2016
Messages
20,523
Likes
37,056
Most though not all interfaces put out around +12dbu or more which is about 3.1 volts. Any that put out +10 dbu (2.45 v) should be okay for your use.
 

Ron Texas

Master Contributor
Joined
Jun 10, 2018
Messages
6,078
Likes
8,914
I briefly owned a Dragonfly 1.2. It sounded great with headphones, but when plugged into my now defunct B&K EX4420 suddenly everything sounded hard, brittle and awful. It stood out like a sore thumb from everything else I ever used with that amp. I can't explain why and I returned the DF.
 
OP
V

vert

Active Member
Forum Donor
Joined
May 30, 2018
Messages
284
Likes
256
Location
Switzerland
So, quick update, I ended up getting this :
https://www.audiophonics.fr/fr/dac-...-384khz-asynchrone-usb-xmos-noir-p-11961.html
I want to thank Amirm and you guys for the great information on this site, I may well have bought a Schitt device otherwise.
As to the DAC I bought, I think it is excellent. I thought the power supply was a real plus over some cheaper devices. I'm not done installing the Stax energizer yet so I haven't done much music listening yet. Some casual listening on ordinary speakers was like listening to a great CD player, as it was supposed to be. Some cheap portable speakers I have were utterly transformed. Not more precise but much much wider. Movies and TV over fiber optics sound great.
 
Top Bottom