Review and Measurements of Schiit Fulla (V1) Dac and Headphone Amplifier

[tjf]

I was thinking the same thing. miniDSP is begging to be measured, IMHO.

I, FWIW, 2nd the motion-to-review a MiniDSP item...especially the "2x4HD" as it seems to be the high value proposition, with XMOS200 USB going to an AKM 6 channel DAC, seems to be a big seller for them currently... tho' I'm not sure how many DIY speaker bi-amp folks read your site...you might be more curious about their DSP headphone DAC/AMP...love to see you dissect that as well!!!!
Also curious to see what you've got to say about their 96K upsampling due to their software platform that works at 96/24...

 

[amirm]

I, FWIW, 2nd the motion-to-review a MiniDSP item...especially the "2x4HD" as it seems to be the high value proposition, with XMOS200 USB going to an AKM 6 channel DAC, seems to be a big seller for them currently... tho' I'm not sure how many DIY speaker bi-amp folks read your site...you might be more curious about their DSP headphone DAC/AMP...love to see you dissect that as well!!!!
Also curious to see what you've got to say about their 96K upsampling due to their software platform that works at 96/24...

Ok, Ok, Ok. I get the message.

I just got the minidsp working and am performing some preliminary tests. Are people interested more in analog in, analog out performance or USB to analog out?

 

[garbulky]

It is 1.6 milliwatt since it is at 150 ohms.

Jeez that's just garbage at 150 ohms. 1.6(!)

 

[stunta]

Ok, Ok, Ok. I get the message.

Are people interested more in analog in, analog out performance or USB to analog out?

It would be interesting to see both. Depending on USB to analog output performance, one may decide to ditch their existing USB DAC. If this is bad and we find the analog to analog performance good, then it means its still usable with an existing DAC and that the USB implementation of the miniDsp is bad.

 

[mindbomb]

Jeez that's just garbage at 150 ohms. 1.6(!)

To be clear, I asked amir to test the channel balance with the volume control, and the point of the volume control dial is to lower the power.

When I bought my fiio a3, I found that the channel balance on the volume control was only good for about 30 decibels or so, and this wasn't low enough for the headphones I was using at the time. So I wish this type of information on amps, particularly the less expensive ones, was more widely available.

 

[restorer-john]

Another test for you: with these amps, make a quick check of the DC output level - should be zero of course. In fact, with all DACs and amps, an extremely important characteristic (as far as I am concerned) is the behaviour at power-off and power-on. Large 'thumps' could damage headphones or blow up speakers. A well-designed device will avoid these problems under any circumstances - it isn't necessarily a trivial problem to solve. Otherwise, you might get something like this:

This is unfortunately, a common occurrence. I have had several inexpensive D/As which exhibit enough DC offset to cause significant speaker cone offset on pure DC pre-amplification and amplification.

I've had DC protectors trip as volume is increased due to poor offset control on some D/A converters. The switch on/off transients and their characteristics can be captured on a decent memory depth DSO for examination.

 

[tjf]

Ok, Ok, Ok. I get the message.

I just got the minidsp working and am performing some preliminary tests. Are people interested more in analog in, analog out performance or USB to analog out?

My vote is for USB or SPDIF IN to DAC/analog output. Not too interested in feeding an analog source to the AKM device, which includes 2 channels of ADC, in addition to 6 channels (only 4 utilized) DAC output...
AKM in question is "AK2646AVQ"--- sorry, this is assuming you're working with the "2x4HD" device...if you are working with the "2x4HD" unit, I suspect you'll get mediocre results, after checking AKM's spec page for the 2646AVQ...

 

[RayDunzl]

miniDSP2x4HD

(with the appropriate driver installed)

The input choices are USB, Analog, Toslink. There are two channels of input.

Output is 4 channels of analog, and those signals also appear on 4 channels of USB Output, in case you want to route the result through the PC to some other DAC or further digital processing.

Either input channel can be routed to any combination of the four output channels.

It is also possible to send both input channels (summing) to any combination of output channels.

High pass, lowpass, bandpass, ten PEQ and attenuation can be assigned arbitrarily to each output channel (analog and USB out).

Ten PEQ and attenuation can be applied to either input.

FIR filters can be applied to each output, but there aren't many taps (4096 shared total) that can be assigned. I haven't tried that function yet.

It seems to permit a choice of rates, though I haven't really verified that yet.

So, there's lots of places available to cause or find problems.

 

[March Audio]

My vote is for USB or SPDIF IN to DAC/analog output. Not too interested in feeding an analog source to the AKM device, which includes 2 channels of ADC, in addition to 6 channels (only 4 utilized) DAC output...
AKM in question is "AK2646AVQ"--- sorry, this is assuming you're working with the "2x4HD" device...if you are working with the "2x4HD" unit, I suspect you'll get mediocre results, after checking AKM's spec page for the 2646AVQ...

My measurements here

https://audiosciencereview.com/forum/index.php?threads/measurements-of-minidsp-2x4hd.2459/

 

[randing]

Yay, I think this is my unit. I was poking around on ASR around this time, sent in my Fulla, then forgot about it. Glad it made it up on the site.

 

[Joe Smith]

I'm using my old v1 today while I wait for my new JDS Atom+ to arrive - delayed because of the big southern storm. The Fulla 1 is still quite pleasant to use with my low impedance AKG K361s. Yes, definitely has a higher noise floor. When I want an easy-out just to headphones, I still rotate this one in, along with my old Fiio e7 unit. Somehow music seems to have a bit more slam with the Fulla, even when I use the Bass +1 adjustment in the e7. I just usually give the volume pot a few back and forth turns before plugging it in, that seems to eliminate most of the scratchiness when using it. The size of the Fulla always makes me chuckle. Schiit did a pretty decent job with it.

 

[Joe Smith]

Using again today down at work (5 months until retirement, whoopee!) with my new Moondrop Chu earbuds with very pleasant results. The original Fulla is still a nice little DAC that's as easy to transport/use as a dongle type unit. For a value-based product, it's held up very well over time.