Who are the competitors for good class A amplifiers?

[davide256]

Starting to delve into an area I really haven't paid attention to. While I don't need a ton of power in a 12x12 room,  Magnepans  behave best with

pristine amplification that behaves well with low speaker impedance and that I don't have. I'm familiar with Pass, their smallest amp the

XA25 is class A and sounds like a good fit but before I spend $5K I'm wondering who the competitors are. No interest at this point in class AB or D amps

[Miska]

Best I know is Accuphase:

https://www.accuphase.com/power_amp.html

 

Both class A and AB offerings.

 

[AudioDoctor]

Pass XA30.8 is another solid option. I was under the impression that Magnepans required a lot of power to drive properly? There certainly are Class A amps that make big power, they also make big heat.

[edn4x4]

I have 1.7 also in a 12x12 room.  I am not sure either of the above mentioned Pass amps would drive them well.

I have been using AVA 400r for mine and wanted to try something different.

The AVA DVA M225 Mono blocks drive them well and sound great.  They just won a couple awards for them and have glowing reviews. 
 

The other is Pass X250.8.  This is what is in my system now and sounds awesome.

 

Bryston amps are also a good match for Maggie’s.

 

I know you said you were not interested in class AB, but in that size room would most likely never leave class A.

 

Hope this helps and feel free to DM if you want additional info as I don’t want to derail your thread with your hunt for pure class A

[davide256]

4 hours ago, edn4x4 said:

I have 1.7 also in a 12x12 room.  I am not sure either of the above mentioned Pass amps would drive them well.

I have been using AVA 400r for mine and wanted to try something different.

The AVA DVA M225 Mono blocks drive them well and sound great.  They just won a couple awards for them and have glowing reviews. 
 

The other is Pass X250.8.  This is what is in my system now and sounds awesome.

 

Bryston amps are also a good match for Maggie’s.

 

I know you said you were not interested in class AB, but in that size room would most likely never leave class A.

 

Hope this helps and feel free to DM if you want additional info as I don’t want to derail your thread with your hunt for pure class A

I'm actually running  1.7's off  1 watt of class A from a Linear Tube Audio MZ2 right now, only problem is triple forte passages and lowest bass. So pretty confident

that the XA's 15db of additional headroom with 50 watts into 4 ohms would suffice for acoustic music, albeit maybe not for death metal or rock concert volumes.

 

Agree that the DVA M225 mono blocks have great reviews and that they would likely stay in class A most of the time with a 300 watts into 4 ohm rating. But they require xlr

input. A positive is that I don't see anyone complaining about excessive break in time for them, unlike the Odyssey Stratos monos. And price per pair is $3400

Not finding anyone with kind words about RCA to XLR conversion but I'll give them a call.

 

The Bryston B cubed amps do have good reviews but aren't class A, are some sort of proprietary Bryston circuit design. A 2.5 B cubed runs about $4300, specs at 180W into 4 ohms.

 

Wow, the Accuphase are pure class A .  Alas, deep pockets required for their price tags

 

The one thing that does worry me about a Pass XA25 in a 12x12 room is its reputation as a space heater, wasn't fun in summer when I had a 4x KT150 tube amplifier before

[edn4x4]

Frank is very helpful, so hopefully you give them a call.  I usually just go over there as he is 15 minutes away as is Magnepan for me. You didn’t mention that you needed SE. You might want to talk to Frank about the Vision Set 400.  I have also heard this with Magnepan 1.6 at a friends house that reviews AVA gear and it was very musical.

[Rexp]

Krell work well with Maggies, you can find plenty on the second hand market. 

[Norton]

https://www.sugdenaudio.com    ?

[mfsoa]

Curious why you feel that Class A will be the best way to go w/ Maggies. They are relatively inefficient and it will take a whole lot of room heating to drive them well. But all best wishes in your quest.

 

I know you aren't considering Class D but here is a data point. The sadly recently deceased Tommy O'Brien of the Digital Amplifier Company (DAC) has a gorgeous Class A Krell amp and his Class D amps had vastly superior SQ on all of the speakers we tried them on. Not close.

 

I have heard his mega power Class D amps replace many a boutique, small-watt tube amp on super efficient speakers and SQ was dramatically improved in all cases.

 

My Maggie 3.6s absolutely love the ~ 700 watts they can receive at 4 ohms from my DAC amp, and my buddy drives his 1.6s with different DAC amp, with beautiful sound quality.

 

Good luck, Happy Hunting

 

 

[davide256]

4 hours ago, Rexp said:

Krell work well with Maggies, you can find plenty on the second hand market. 

New price isn't that bad for a Krell Duo 125 XD, ~$7500 for 250 watts into 4 ohms of class A, has both xlr and RCA inputs. Haven't heard one since the early 80's, they and Threshold

were still "works in progress" at that time.

[botrytis]

36 minutes ago, davide256 said:

New price isn't that bad for a Krell Duo 125 XD, ~$7500 for 250 watts into 4 ohms of class A, has both xlr and RCA inputs. Haven't heard one since the early 80's, they and Threshold

were still "works in progress" at that time.

Krell is not the same Krell as from the 80's. The designer, from that time, is no longer with Krell and has his own company.

[mfsoa]

Krell says that even back then, that that original designer who now has his own company had little to do with the designs of the equipment.

[Rexp]

9 hours ago, mfsoa said:

Curious why you feel that Class A will be the best way to go w/ Maggies. They are relatively inefficient and it will take a whole lot of room heating to drive them well. But all best wishes in your quest.

 

I know you aren't considering Class D but here is a data point. The sadly recently deceased Tommy O'Brien of the Digital Amplifier Company (DAC) has a gorgeous Class A Krell amp and his Class D amps had vastly superior SQ on all of the speakers we tried them on. Not close.

 

I have heard his mega power Class D amps replace many a boutique, small-watt tube amp on super efficient speakers and SQ was dramatically improved in all cases.

 

My Maggie 3.6s absolutely love the ~ 700 watts they can receive at 4 ohms from my DAC amp, and my buddy drives his 1.6s with different DAC amp, with beautiful sound quality.

 

Good luck, Happy Hunting

 

 

I'm open to the idea that class D can be good but I also know some class D makes poor digital sources sound better.

[mfsoa]

If they make poor digital sources sound better (not sure how that's possible) then you should hear what they do w/ good digital.

[sootshe]

The latest Luxman range has a gorgeous Class A offering.

[fas42]

I had personal experience, at an audio show, of the smallest(?) Magnepans being driven by a Magtech amplifier - which are designed to handle this sort of load. SQ issues were all because of less than optimal digital source setup; when the demonstrator used the better source mechanism, I couldn't pick any problem with what I was hearing, at all.

[botrytis]

13 hours ago, fas42 said:

I had personal experience, at an audio show, of the smallest(?) Magnepans being driven by a Magtech amplifier - which are designed to handle this sort of load. SQ issues were all because of less than optimal digital source setup; when the demonstrator used the better source mechanism, I couldn't pick any problem with what I was hearing, at all.

 

It has nothing to do with the fact that the smaller maggies do not have a treble ribbon, like the bigger maggies. I have heard the latest version and the previous SMG and found them rolled off for bass and treble.

 

How do you know it was less than sub-optimal? It could have to do with the mastering of that particular file.

 

They are a good entrance, if you like the sound of maggies and Magnepan does stand behind their speakers. I applaud them for that.

[davide256]

The reason Maggie owners buy n x 100 watt amplifiers is bass sucks up all the wattage with Maggies and still rolls of sharply at 32hz. Likewise the treble

is very directional, a PITA to position for imaging and pretty much a 1 person listening position.

On 1/17/2022 at 9:47 AM, mfsoa said:

Curious why you feel that Class A will be the best way to go w/ Maggies. They are relatively inefficient and it will take a whole lot of room heating to drive them well. But all best wishes in your quest.

 

I know you aren't considering Class D but here is a data point. The sadly recently deceased Tommy O'Brien of the Digital Amplifier Company (DAC) has a gorgeous Class A Krell amp and his Class D amps had vastly superior SQ on all of the speakers we tried them on. Not close.

 

I have heard his mega power Class D amps replace many a boutique, small-watt tube amp on super efficient speakers and SQ was dramatically improved in all cases.

 

My Maggie 3.6s absolutely love the ~ 700 watts they can receive at 4 ohms from my DAC amp, and my buddy drives his 1.6s with different DAC amp, with beautiful sound quality.

 

Good luck, Happy Hunting

 

 

 I try to avoid technology thats still at the bleeding edge, thats where I would place class D for market stage.

Hopefully in 3-5 years Class D will sort itself out for best  design principals and hardware solution.

[cjf]

Not sure if the OP is aware of this info related to Pass Labs amps but most of the Amps they make, even the ones considered A/B, still offer some number of Class A watts before going A/B mode. This is good because it opens up your options a bit when shopping around on the New or Used market.

 

Below is a chart from one of Nelson's Tech articles on "Leaving Class A".

 

 

I'm not able to find it anymore on the Pass website but there used to be an equivalent document to the one linked below for the .8 series showing the wattage output of Class A power for the older model Pass Labs amps classified as A/B units (ie..X150,X250...etc). In short, most of them have at least 10watts of Class A on tap.

 

https://www.passlabs.com/wp-content/uploads/2019/12/Point8_specs_8.pdf (Scroll to bottom for Class A/B amps and look for Leaves Class A)

[cjf]

On 1/16/2022 at 2:52 PM, AudioDoctor said:

Pass XA30.8 is another solid option. I was under the impression that Magnepans required a lot of power to drive properly? There certainly are Class A amps that make big power, they also make big heat.

Looks like there is one of these for sale now on Audiogon for a decent price (I'm not the seller but noticed it). I think the XA30.8 would be a perfect fit for the OP.

 

I've never really noticed the heat concerns with any of the Pass units I've owned in the past or currently. In the past I've ran a large X250 in a pretty small room and never noticed much added heat in the space as a result. But with that said, maybe I'm just oblivious and its there without me really thinking about it.

 

I think my XA60.8's run even cooler than the old X250 did. They are currently running at 103deg on the top plates of both and that is after about 4hrs run time at "energetic" output levels. 😀

[AudioDoctor]

26 minutes ago, cjf said:

Looks like there is one of these for sale now on Audiogon for a decent price (I'm not the seller but noticed it). I think the XA30.8 would be a perfect fit for the OP.

 

I've never really noticed the heat concerns with any of the Pass units I've owned in the past or currently. In the past I've ran a large X250 in a pretty small room and never noticed much added heat in the space as a result. But with that said, maybe I'm just oblivious and its there without me really thinking about it.

 

I think my XA60.8's run even cooler than the old X250 did. They are currently running at 103deg on the top plates of both and that is after about 4hrs run time at "energetic" output levels. 😀

 

Or we just have different levels of what we consider acceptable amounts of heat production. I don't mind so much in a MN winter, but on a hot summer day it bothers me some.

[botrytis]

I only use my class A in winter, a rebuilt Pioneer M-22. I had it, previously, in a listening room in a basement which was 38 ft x 11 ft. The room in winter, which could get to 62 F w/o the amp on and would be at 85 F with the amp on. Stellar sound for a space heater 🤣

[davide256]

Have ordered a Schiit Aegir after discussing on Audiogon. 20 watts for $800, and a relatively inexpensive way to see if class a will be too much of a space heater in my listening room

[davide256]

Aegir received and burning in, sounds a little syrupy and congested at the moment but harmonically more correct than the Hafler amp. Trying to make it

"misbehave" but no issues so far at normal listening levels.

[AudioDoctor]

1 hour ago, davide256 said:

Aegir received and burning in, sounds a little syrupy and congested at the moment but harmonically more correct than the Hafler amp. Trying to make it

"misbehave" but no issues so far at normal listening levels.

 

You're running Magnepans with an Aegir amp?