Premium Audio Mini GaN 5 Review (Stereo Amplifier)

[Mulder]

I bought a stereo amp from Premium Audio to run my ridiculously inefficient Stax F81 Electrostatic speakers. I liked it enough to ask Tom to make me mono blocs. They run cool and with zero issues, sonically they best my Rogue Medusa my NuPrime mono’s and Ghent Audio mono’s. More detailed less haze than any class D amp I have used. Bass is exceptional with a smooth extended top. Midrange is a little more forward than other amps but that ok. Value for money is outstanding. I understand measurements are important, but if I measure some of the tube amps I love I think I would be just as shocked. I say let your ears be the judge.

You are in the wrong place if this is what you beleive in.

 

[0hm357aW]

This is a review and detailed measurements of the Premium Audio Mini GaN 5 Stereo Class D power amplifier. It was kindly sent to me by a member and costs US $799 (recent price increase).

The GaN 5 comes in a compact enclosure with plenty of ventilation at the cost of decent looks:

View attachment 157253

Beside the sole power button and blue indicator, there are two red LEDs that turn on when you power the unit on and then go off. Strangely, when the amplifier goes into protection, they do not light up and getting the unit working again requires a power cycle. I like to see protection circuits that self recover when the extreme condition goes away.

The back panel shows binding posts that are too close together for easy fitment of my large banana speaker cables. But I like the inclusion of balanced XLR inputs:

View attachment 157254

As you see, there are also jumpers to change the gain setting although the range is not very large (26, 28 and 32). Most of my testing was with medium gain which is as shipped.

I had trouble getting the amplifier to function initially. It would simply not output anything. I played with grounding as I have seen some very low end amps cause AP to not be able to capture their output due to high level of noise (despite my use of AES-17 filter). This didn't work at first so I switched inputs to RCA. That did not work either. After some fiddling and switching back to balanced input, the amp all of a sudden started to work. Not sure how much of this is interaction with Audio Precision or design issue. Either way, it is an exception to the rule of 95% of amplifiers I have measured.

As the name indicates, this amplifier uses the new Gallium Nitride transistors (GaN) which has some advantages over classic Mosfet transistors. All else being equal, it can produce higher efficiency and better performance at expense of higher cost.

Mini GaN 5 Measurements
As noted, I started my testing in medium gain which produced near nominal 29 dB which is my standard for amplifiers. XLR input was used per introduction:

View attachment 157255

Well, this is disappointing. Distortion is fairly high causing SINAD which is the sum of distortion+noise to be worse than a number of budget desktop amplifiers:

View attachment 157256

Noise performance by itself is not good either:

View attachment 157257

I had trouble getting the amplifier to go to full power for the right graph. It would shut down at just 0.7 volt input. Strangely, later on it accepted higher levels of input. I think the impulse nature of this measurement was causing it trouble. So maybe it can produce higher SNR at higher power but still, none of this is competitive.

On the other hand, crosstalk was very good:

View attachment 157258

Multitone performance was also reasonable:

View attachment 157259

What is not reasonable is high dependence on speaker load when it comes to frequency response:

View attachment 157260

This is just not proper. Clearly the output filter is interacting with the load.

Power measurements were quite puzzling:

View attachment 157264

Notice the pull back due to some protection kicking in, likely the power supply rather than the amplifier. I could not remotely get the power rating they specify using medium gain. I thought maybe low gain does better but then the pull back occurred at even low power (blue and green)! Beside lack of power, distortion is also quite high for this price class and category. We are talking about poor Audio/Video Receiver amplifier performance!

Switching to 8 ohm tamed the output a bit but power shortfall is still significant:

View attachment 157268

This being the second amplifier I have recently tested with such power shortfall, I started to doubt my instrumentation. So I pulled out my Purifi reference design and measured it. It tracked the dashed line in the above graph from a year ago 100%. Someone had posted this from their website:

600 watts per channel??? Into 8 ohm? This is the spec from the manual:
View attachment 157269

How on earth did they measure 600 watts when the spec is 200 watts? Strangely, that graph is nowhere to be found on their site. There is some talk about a larger amplifier of which is a shrunk version? Maybe that is the one that produced higher power but why does it say "mini" in the title of above graph?

FYI, this amplifier has the green board which I understand to be the newer design. Maybe the older red one had more power. Hard to say.

Anyway, I tried to run my max and burst power:
View attachment 157272

In Burst mode, the amplifier would keep going into pull back and so I could not compute anything for that. Likewise the THD+N vs frequency and power could not be run. As the frequencies got lower and lower, the point where the amp would pull back would also shrink to lower and lower wattages. What I could get did not show great transfer function.

Conclusions
While I leave the door ever so slightly ajar to some interaction with Audio Precision, the measurements seem to indicate an amplifier that has both design issues and inability to meet specifications. The fact that the company took away the only measurement graph makes it suspect that maybe they had have modified the design and selling something different than what they originally intended. As it is, it is a waste of GaN technology as it brings nothing to the party but high expense.

I can't recommend the Premium Audio Mini GaN 5 amplifier.

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As always, questions, comments, recommendations, etc. are welcome.

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/

Looks like you got a dud based on problems you reported.

 

[0hm357aW]

Did you mean, " .... got a dud..." or did you mean, ".... is a dud .... "? Jim

Got a dud. The review included problems with getting it to work which makes me think this particular Mini Gan 5 has a problem and shouldn't be used as sample for the review. Has unknown, unidentified fault.

 

[0hm357aW]

Green PCB board? Did it have the wire bound coil inductors or the ceramic chip inductors?

 

[0hm357aW]

Maybe the instrimentation device used to measure isn't applicable to this amp technology.

Any music listening impressions?

 

[JSmith]

Maybe the instrimentation device used to measure isn't applicable to this amp technology.

Yes only 5G capable Martians can measure this device...


JSmith

 

[antcollinet]

Maybe the instrimentation device used to measure isn't applicable to this amp technology.

Any music listening impressions?

 

[BDWoody]

Maybe the instrimentation device used to measure isn't applicable to this amp technology.

Any music listening impressions?

What instrumentation device would be more appropriate? Any suggestions?

Just because you enjoy yours, doesn't mean the way it was tested is faulty.

 

[0hm357aW]

pWhat instrumentation device would be more appropriate? Any suggestions?

Just because you enjoy yours, doesn't mean the way it was tested is faulty.

Yes I greatly enjoy mine. It sounds great to my ears. I think its enclosure is functional as well as the heatsinks that do make contact with hot spots on mine. Also in a dark room its enclosure emits out a beautiful pattern of blue light from the pcb leds that reflects off of the nearby walls. It's an amazing functional industrial design that I like.

Also I'll add Class D audio does back up their products with great customer support. I have read other amp speaker driver reviews here with photos of inside of enclosure. Why no photos of the PCB/power supply of the interior of this enclosure for this PCB? Maybe there was a dead roach on the PCB?

It's obvious this review of this particular PCB has some faults or user operator faults that were not identified. Because my personal experience with Class D and this particular amp has been outstanding and it drives my speakers beautifully to resonate fantastic sounding music I stick with what I know and do question the review results with this particular review.

I absolutely would not hold this single sample review as a means to not recommend it. It's just one review. I don't fully understand the instrumentation testing used or conditions compared to other speakers.

To my ears this amplifier is very dynamic in driving audio sounds/signals to my ears. It controls the mechanics of my speakers and produces amazing music/audio sounds.

Really this quality of amp is amazing and I'm sure there are some great musicians/studios out there mastering their recordings with it.

 

[Vladimir Filevski]

It's obvious this review of this particular PCB has some faults or user operator faults that were not identified. ... I stick with what I know and do question the review results with this particular review.
I absolutely would not hold this single sample review as a means to not recommend it.

You are contradicting yourself:

I don't fully understand the instrumentation testing used ...

You are questioning this review, but you know nothing about "the instrumentation testing"?
Please stop embarrassing yourself.

 

[0hm357aW]

You are contradicting yourself:

You are questioning this review, but you know nothing about "the instrumentation testing"?
Please stop embarrassing yourself.

I didn't read about what exact instrument device was used for the testing. I read the review. I don't understand the tool, conditions, or logic behind the test. I'm not embarrassed. A good explanation of the instrumentation and methods for this test would be beneficial... Also was the instrument properly calibrated and if so by what method.

 

[Killingbeans]

Also I'll add Class D audio does back up their products with great customer support.

Class D Audio USA is a distributor? The manufacturer is Premium Audio Products?

To my ears this amplifier is very dynamic in driving audio sounds/signals to my ears.

No doubt it is.

I remember reading about a blind test where a group of people wanted to test whether they could hear the difference between different types of amplifiers. Only one of the amps sounded different, a cheap Class D board from eBay. So Class D sounds different? No. They did some further investigation, and it turned out that the poor little amp board had just been pushed to a crazy amount of clipping.

The Mini GaN 5 probably sounds just fine, but is it something special?... I doubt it.

GaN technology has great potential for making amps more energy efficient, but the idea of sonic revelations is far fetched, IMO.

 

[Vladimir Filevski]

I didn't read about what exact instrument device was used for the testing. I read the review. I don't understand the tool, conditions, or logic behind the test. I'm not embarrassed. A good explanation of the instrumentation and methods for this test would be beneficial... Also was the instrument properly calibrated and if so by what method.

You know NOTHING, bur you still are questioning the test?!

Testing equipment is Audio Precision APx555, the state-of-the-art analyzer:
https://www.audiosciencereview.com/...s-a-new-audio-precision-analyzer-apx555.3442/

Logic of the test is simple - to objectively test the audio equipment.

You don't have the slightest idea how and when the measuring equipment should be calibrated, and surely you don't know what are the methods for calibrating. Why are you asking this, when the answers would mean nothing to you?

And yes, you are embarrassing yourself, big time.

 

[0hm357aW]

You know NOTHING, bur you still are questioning the test?!

Testing equipment is Audio Precision APx555, the state-of-the-art analyzer:
https://www.audiosciencereview.com/...s-a-new-audio-precision-analyzer-apx555.3442/

Logic of the test is simple - to objectively test the audio equipment.

You don't have the slightest idea how and when the measuring equipment should be calibrated, and surely you don't know what are the methods for calibrating. Why are you asking this, when the answers would mean nothing to you?

And yes, you are embarrassing yourself, big time.

No. You are side stepping my questions and apoear to be trying to embarass me. I'm not embarrassed in the slightest and thanks for giving tip on testing instrument used.

 

[Vladimir Filevski]

You are side stepping my questions... and thanks for giving tip on testing instrument used.

Wrong. I do answer two of your questions:
1) About the testing instrument (APx555) - it is not a tip, but full answer, plus link to more detailed information.
2) About the logic of the test - to test objectively audio equipment.

I am not sidestepping your other questions - about proper calibration and method of calibration. But those questions are just silly! Even if I give you those answers, will you understand them? How many methods of calibration do you know, and which are they?

 

[Vladimir Filevski]

Maybe the instrimentation device used to measure isn't applicable to this amp technology.

 

[antcollinet]

No. You are side stepping my questions and apoear to be trying to embarass me. I'm not embarrassed in the slightest and thanks for giving tip on testing instrument used.

You accuse your host of implementing faulty tests, and then confess you have no idea about the test methods or equipment, and even if you did, you don’t understand them.

Even if you are not embarrassed, you should be.

 

[orchardaudio]

Yep, knew that. Sorry, I meant the new Starkrimson Ultra.

May issue of Audio Xpress. Thanks @SIY for putting in the work.

 

[abdo123]

May issue of Audio Xpress. Thanks @SIY for putting in the work.

ooof what a beast! I'm a bit concerned about the input sensitivity though! if you need 2.5/5 Volts for 500W output you would need some really unorthodox amount of voltage for the peak 1000W output!

 

[orchardaudio]

ooof what a beast! I'm a bit concerned about the input sensitivity though! if you need 2.5/5 Volts for 500W output you would need some really unorthodox amount of voltage for the peak 1000W output!

I am not quite sure what you mean. The balanced input has a gain of 19.05dB (8.96V/V)

So 5Vrms on the input gives you 44.8Vrms on the output, that is 500Wrms into 4ohm, or 1000Wpeak as the peak power of a sine wave is double its rms value.