Review and Measurements of Schiit Aegir PWR Amplifier

[March Audio]

Since @amirm always puts a reference curve at the same time (here it's the ABH2} it quite easy to separate the good from the average in terms of behavior before clipping.
In terms of limit, I vote for 1%. 0.1% may simply exclude some amplifiers from the test, and 1% allows the amplifiers with clean behavior at the limit to be gratified with a nice power score.

The references are indeed really helpful.

Are we sure we are interested in amps that cant get below 0.1%? Otherwise it just means their rated power will be lower, it doesnt really exclude any competent amps.

 

[boXem]

The references are indeed really helpful.

Are we sure we are interested in amps that cant get below 0.1%? Otherwise it just means their rated power will be lower, it doesnt really exclude any competent amps.

I am not sure that "sorry, too bad to be tested here!" is an efficient message.

 

[RayDunzl]

Are we sure we are interested in amps that cant get below 0.1%?

I guess mine are borderline...

For now I'll just have to pretend I have a pair of good amps...

Measurements likely similar to this:

"Formally defining clipping as the 1% THD+noise figure gave maximum power delivery of
a monstrous 475W into 8 ohms (26.8dBW), way above the specified power. 850W was
available into 4 ohms (26.3dBW) and while I measured 1060W into 2 ohms (24.2 dBW)
rather than the specified 1400W, the AC line in our Santa Fe office was sagging significantly
for this measurement.

Fig.7 Krell FPB 350mc, distortion (%) vs continuous output power into (from bottom to
top at 2kHz) 8 ohms. 4 ohms, and 2 ohms."

--- Aug 10, 2000 -- https://www.stereophile.com/solidpoweramps/266/index.html

Mine is the next year model, made in 2005, I think, FPB 350 mcx - also spec'd at 350/700/1400W @ 8/4/2 Ohms

Green?

Nope.

30W (x2) standby, 100W (x2) idle, bias current step up under higher output signal, have definately seen 1kW for the pair during enhanced listening sessions.

But they have paid for the whole system by nudging me into buying some Electric Utility shares which has produced a remarkable capital gain and continuing dividend payments.

Go figure.

Oh, here's a nice picture of that model with the matching preamp. Only $9,999.00 for the set at Audiogon.

Disclaimer:

I can casually listen all day to the economically operating co-located pair of JBL LSR 308 and not feel cheated, until I sit in the middle and pay attention to the imaging, or try to turn them up too loud.

 

[boXem]

What about something in the middle, like 0.2 or 0.3%?

 

[March Audio]

I am not sure that "sorry, too bad to be tested here!" is an efficient message.

What amps are going to be excluded though? Are all valve amps above 0.1% across the power range?

 

[March Audio]

I guess mine are borderline...

For now I'll just have to pretend I have a pair of good amp...

Measurements likely similar to this:

"Formally defining clipping as the 1% THD+noise figure gave maximum power delivery of
a monstrous 475W into 8 ohms (26.8dBW), way above the specified power. 850W was
available into 4 ohms (26.3dBW) and while I measured 1060W into 2 ohms (24.2 dBW)
rather than the specified 1400W, the AC line in our Santa Fe office was sagging significantly
for this measurement.

View attachment 35644
Fig.7 Krell FPB 350mc, distortion (%) vs continuous output power into (from bottom to
top at 2kHz) 8 ohms. 4 ohms, and 2 ohms."

--- Aug 10, 2000 -- https://www.stereophile.com/solidpoweramps/266/index.html

Mine is the next year model, made in 2005, I think, FPB 350 mcx - also spec'd at 350/700/1400W @ 8/4/2 Ohms

Green?

Nope.

30W (x2) standby, 100W (x2) idle, bias current step up under higher output signal, have definately seen 1kW for the pair during enhanced listening sessions.

But they have paid for the whole system by nudging me into buying some Electric Utility shares which has produced a remarkable capital gain and continuing dividend payments.

Go figure.

Its only marginal at 2 ohms which is not a figure I would advocate as representative of "normal" speaker loads

 

[boXem]

What amps are going to be excluded though? Are all valve amps above 0.1% across the power range?

I don't intent to review the datasheets from all the products I am not interested in .
I am maintaining my 0.2% offer. That would avoid taking the risk to rate Ray's monster amps at 10W into 2 ohms.

 

[RayDunzl]

Its only marginal at 2 ohms which is not a figure I would advocate as representative of "normal" speaker loads

I don't do normal...

Prior year's model for my load:

I popped the 15A breaker 80 wire feet away running a slowish sweep at a somewhat elevated level, so, I don't do that any more.

Don't remember popping it during musical excursions, though.

 

[peng]

Since @amirm always puts a reference curve at the same time (here it's the ABH2} it quite easy to separate the good from the average in terms of behavior before clipping.
In terms of limit, I vote for 1%. 0.1% may simply exclude some amplifiers from the test, and 1% allows the amplifiers with clean behavior at the limit to be rewarded with a nice power score.

Then we should have it for both (0.1 and 1%), otherwise the 1% will offer little value in differentiating devices that show THD+N <1%, unless the measurements always include the harmonics vs frequency and square wave etc..

 

[Matias]

View attachment 35644
Fig.7 Krell FPB 350mc, distortion (%) vs continuous output power into (from bottom to
top at 2kHz) 8 ohms. 4 ohms, and 2 ohms."

@March Audio problem with using 0.1% THD is that some amplifiers like this would have their power levels underestimated, in this case possibly 15W or so.

This Simaudio Moon 400M mono amplifier would do 0.2W only. Edit: in fact the 2 upper lines below are IM distortion, but the point remains.

https://www.soundstagenetwork.com/i...-moon-400m-mono-amplifier&catid=97&Itemid=154

 

[Dana reed]

One was offered but there was no follow up. Let me circle back with him.

That was me. Then I started using mine every day because I didn't like the new Red Dragon M1000 mkII I'd bought, so my motivation to have it measured was outweighed by my desire to use them every day.

 

[KSTR]

But isn't that just as arbitrary as 1%?

If the purpose is to catch an amp that misbehaves under the limit, maybe some kind of deviation spec (similar to ±3 dB) should be used.

Tom

Or a relative distortion figure, the point when the (clipping-induced) distortion raises more than 20dB (or whatever reasonable value) above the (non noise-limited) best THD point, with some sane boundary limits (say, more than 0.1% but less than 3%).

 

[birkbott]

I have a set of Spatial Audio M4s that I've been running with a Rogue Audio Sphinx v2 for about a year.

I just ordered an Aegir along with a Saga S, Modi 3 and Mani from Schiit.

The M4s are 93dB sensitive at 4 ohms. I'm not worried about power.

I have never owned a class A amp so I guess I want to see what all the fuss is about. If all else fails they have a 15 day return policy.

Feel free to praise and/or excoriate my decision.

 

[Panelhead]

If the M4 are 93 dB efficient the pairing will be fine.
The damping factor may less than most solid state.

 

[birkbott]

If the M4 are 93 dB efficient the pairing will be fine.
The damping factor may less than most solid state.

Schiit rates Aegir at >100, Rogue rates Sphinx at >1000. As I understand it anything over 100 is desirable so I should be OK.

I will be sure to post my listening impressions back here when I get it hooked up.

 

[gvl]

News flash. The Schiitr is in danger.

 

[restorer-john]

Amir measured some amps at clipping and found some very ugly waveforms, much worse than I'd have expected in this day and age.

Amir's "clipping" scope plots above are a long way into clipping- he knows that.

It is the behaviour right at the onset of clipping or transient overload recovery that are illustrative of the stability of these amplifiers- something rarely tested or commented on these days.

Here's the distortion meter's residual (not to scale) showing a little Rotel amplifier I was restoring. Notice how the clipping is slightly non-symmetrical.

Probe attenuation was x10, approx 35W@8ohms.

 

[March Audio]

@March Audio problem with using 0.1% THD is that some amplifiers like this would have their power levels underestimated, in this case possibly 15W or so.

This Simaudio Moon 400M mono amplifier would do 0.2W only.

View attachment 35744
https://www.soundstagenetwork.com/i...-moon-400m-mono-amplifier&catid=97&Itemid=154

To my mind a good reason to not buy the amp.

To put it into context compared to other equipment measurements, 0.1% is thd + n SINAD of around 60dB. An amp that can't acheive that in its "normal“ operating range should be thrown in the trash.

I think common sense can be applied in circumstances where a low impedance test takes the amp over the limit. Just a few words in the review text to explain, but I don't think Amir does tests below 4 Ohms so shouldn't be an issue.

 

[yodog]

One was offered but there was no follow up. Let me circle back with him.

please do! Would you ever be interested in testing any products from Musical Fidelity’s integrated amplifiers?

 

[birkbott]

Got my Schiit today, here goes.

Compared to the Rogue Audio Sphinx here are my initial impressions:

-midrange is more “sweet”, I wouldn’t call it warm, just nicer in a way that’s hard to describe, I guess this is the class A
-highs are sparkling along the lines of the sphinx
-bass is adequate, maybe not as thunderous or impactful as the class D in the Sphinx but definitely not lacking or weak
-using the saga s preamp I found that to get the volume “sufficiently loud” I had to turn it up to about 1 or 2 o’clock which is way more than I had to do with the Sphinx so that’s the power difference.

I am scared to turn it up all the way but I had it pretty close and didn’t hear anything unpleasant or distorted (will I hurt my speakers if I do turn it up all the way? Experts please tell me)

Using the Amazon HD app via my Mac and the Modi 3 is VASTLY superior to using airplay from my phone through my Yamaha streamer.

It does run warm but not super hot.

That’s all I got for now, very nice amp in my opinion.