Schiit Aegir Power Amp Impressions

Bridged amps "see" only half of the load for each stage. Let's look at the impedance curve of the ESL-63



At 10-11kHz it will get into danger zone for sure. Everything generally depends on two things - amp stability and current capability. At 10kHz there generally isn't that much energy, so I wouldn't fret about that. Stability at 2 Ohms might be a more interesting matter. Pretty sure Schiit's smart protection will kick in before you're in trouble.

 

It is not the impedance of the speaker that drops. It is how the amplifier behaves when bridged. There is a reason why Jason does not give the Aegir or Vidar a 4 ohm rating when in mono.

https://www.researchgate.net/post/Why_do_bridged_amplifier_outputs_see_half_the_load_impedance2

 

You disagree like the guy who using a Honda Civic towing a 3 ton boat. Sure, if you keep it in the lower gears, make sure you have 500 ft of braking distance everywhere you go, choosing a route that minimized contact with johnny law...

 

In this size room and at mid 80's DB at listening position this is a bad comparison. What do you listen to 100 dB??
Sure they don't play VERY loud, but I never play very loud. I want top keep my hearing. And if everything that is to be heard is available there is no need to play loud. Most loud playing is a very bad compromise for something lacking and trying to compensate it with volume. You should hear it to understand it.
Let's look at the impedance curve of the ESL-63
That is the normal impedance curve of an ESL-63 with graphite coating and all the related electronics for protection in it. We do not use graphite or any other conductor as coating, so the ESL plays 100% electrostatic. Only clamp boards for stator-stator arcing protection that limit to 7000V, all the rest is out. A real electrostatic speaker now IMHO. Took us 4 years to solve the problem for a coating for the Quads. We call it ESL PLus.
Be aware that mono blocks will sound slightly different
I guess that's OK, was the same with Vidar, for a dipole it is most likely an improvement. That was my experience with Vidar.
It is how the amplifier behaves when bridged
Jason Stottard has already explained several times in his blog: Vidar and Aegir in mono are NOT bridged.

 

The lowest the ESL-63 gets is 3.66 Ohm (as shown in th graph). It comes nowhere near 2 ohm, or it must be above 30 kHz. I thunk you're confusing the ESL-63 curve with the original ESL (57). That model goes down to 2 ohm.
Top is ESL-63, bottom is ESL-57

 

Herb Reichert's review of Aegir is up on Stereophile: https://www.stereophile.com/content/schiit-audio-aegir-power-amplifier

Spoiler: he really likes it.

 

Hey Jason @schiit, any further info on the 49w limit Stereophile hit driving the Aegir as monoblock into 8 ohms? Did you get the review unit back?

 

No clue, they test fine here. Our measurements are up on the site.

 

Just a Rando here, but hopefully your next Continuity amp will have 27db of gain, 80 watts mono is fine, but gain mismatch with Vidar is killing me. I have the Nao Note Speaker (Active Crossover for bass and mids) - Vidar is perfect for the woofer that uses Linkwitz transform, but need an amp with good imaging and soundstage for the mids

 

I've always wondered if it would be possible to order a Vidar from Schiit with the same amount of gain that Aegir has. I don't know how gain is set in an amp, if it's a hardware deal, or a programming thing.

 

It's hardware, unfortunately. And also critical for stability of the amp, so we won't be offering gain options.

Best to pad down the input to Vidar to match if you need to match gains. Or go to an active crossover, which is what I'd do personally. (Sorry, no, I don't want to design one, it seems very very very niche.)

 

As @purr1n suggested previously, put a SYS between your preamp and Vidar to bring down the gain to match the Aegir.

Edit: ^What he said!

 

Thanks schiit for the response, I figured it wasn't an easy deal.

Also, the sys trick sounds like an easy & stable fix. Thanks guys!

 

I picked up a used one for a decent price. I'll give impressions after the weekend.

I'll try it in a couple of configurations.
Hegel preamp outputs -> Aegir
Audio GD Master 9 -> Aegir
JRiver digital volume control--> Yggdrasil A2 --> Aegir

Caveat: My speakers are open baffle planars for the mids and highs with powered stereo dual open baffle subs for the low end. SO I will not be posting impressions about how the Aegir does on the low end of things.

 

I keep going back and forth on ordering an Aegir to try out...

I had some spare towers just sitting collecting dust, so I decided to setup a dedicated 2 channel system in a smaller room using a single Vidar (I poached it from my main system while I'm running my original monoblocks) and I'm thinking that even though the towers are lower sensitivity, a single Aegir should perform nicely in this application. I know they wouldn't work in a monoblock configuration since my towers are 4 ohm and they tend to go into over-current protection way to easy, however I'm thinking that 4 ohm stereo would work out quite well, even with only 40 watts it should still allow them to put out 105 dB or so at 1 meter. I'm only sitting 2 meters away, so they would still be able to play plenty loud...

Decisions, decisions, decisions...

 

Forgot to mention, the Active crossover is balanced out- Sys is Single Ended.
Current setup: Cayin iDac-6 (To be replaced with a Yggdrasil soon) -> Active Crossover -> 2 x Balanced TVC Preamp -> 4 x Emotiva XPA-1 (1st Gen with 32 db gain) -> Nao Note Speaker.

I am keeping the TVC preamps -> very transparent for the price, but need to get rid of the 4 x Emotiva (occupy too much space and do not have good imaging and soundstage - typical for a Class AB amp)

TVC preamp does not work very well if the amp does not have enough gain (27 gain db is enough for the TVC - but 22db is definitely not sufficient). Sorry for my rant, I will just delete everything if it adds too much noise to this thread

 

Update.

So apparently the Hegels variable outs are a bit gimped so I can't get a fair comparison of the Aegir and the H360's amp using the H360s preamp. The soundstage with the Aegir in this config is flat and the sound lacks alot of tonality. I usually use these outputs to send a signal to my sub amps that have alot more gain so I have never realized how low powered they are.

I have yet to run the Aegir direct from the Yggdrasil. This takes some time on my part because I have to change settings in Jriver Media Center and then double and triple check things so I don't accidentally send a full volume signal to my amp. Just fyi and IIRC the last time I tried this I was comparing an AGD Master 1 and a Wyred 4 Sound STP SE to the direct outs of the Yggdrasil. Between the M1 and the Yggdrasil outs I didnt notice any real major differences in sq other than the M1 expanding the soundstage in all directions (which was my preference) and the direct outs of the Yggdrasil being a bit more incisive and quick sounding. I won't mention the Wyred b/c it was outclassed - 6moons be damned. I think the Wyred shorts its inputs so maybe that is what happened, IDGAF. The amps I used in this comparison were these https://www.cherryamp.com/king-60v-desktop-marachino-dtm

Anyway...

Master 9 --> Aegir. So far I think this combo is at least equal to the H360. So by my math that is approx $2230 = $5700 original msrp for the Hegel (I got mine way used thank goodness). The Aegir is a bit more warm than the H360. At lower volumes this warmth makes it seem as if the Aegir has a slightly less wide soundstage than the H360 - but the soundstage expands significantly with each uptick of the Master 9's volume - and oh the slight warmth is still there (fantastic). Soundstage height and depth are equal to the H360. Details, plankton, attack, decay all that stuff - equal to the Hegel. This is a $800 amp... f%#k! The Hegel does seems to layer center images slightly better than the M9/Aegir combo so that is the basis for my "at least equal to" caveat. The Hegel can sometimes do some uncanny soundstage layering. I need further listening with stricter volume matching to confirm that the Aegir falls short here.

I was really anxious about spending money on this amp even at a used price because, other than the Fulla 2, I have not had a lot of luck with Schiit headphone amps but this thing is seriously legit. From here on out my impressions might be tainted with confirmation bias because I am daydreaming about on running a pair of Aegirs and pocketing some cash.