[Doublej]

I have a friend looking for an integrated tube amplifier to connect to a pair of Martin Logan Aerius loudspeakers. Can he find joy for under $700?

[jsm71]

The Aerius's sensitivity is 89db and recommends amplification of at least 20 watts.  That alone puts you into a tube amp at least a couple of thousand dollars new.  An integrated would be more.  Used would need to be very, very used to be under $700.  Maybe something vintage and needing some work.

 

[rollo]

  Peachtree check them out. Not a dealer. They need current.


charles

[BobRex]

I'd forget about the tube integrated for driving the Aerius.  ML panels are notorious for being almost purely capacitive at higher frequencies.  You need power to get around this, and tube power ain't cheap, even used. 

[I.Greyhound Fan]

Vincent makes a hybrid tube integrated amp for about $1K, 80wpc at 4 ohms-

http://www.audioadvisor.com/prodinfo.asp?number=VISV500

But I agree, a high current amp would be best.

[Rocket_Ronny]

Best sound i heard out of logans was with a Jadis Orchestra. Way out of the budget though.

[dolsey01]

Peachtree has Refurbished Nove225SE on thier website for $999.  Back in the day I ran my Aerius with a Denon AVR2500 which was only 80Wpc and had more than enough power for them.  I used to sell them all the time with a Audio Research LS7/VT60 combo which had just enough power for most listening. 

The Rogue Sphinx would be another option and they have been selling lately for $850-900 on the used market.

[FullRangeMan]

I'd forget about the tube integrated for driving the Aerius.  ML panels are notorious for being almost purely capacitive at higher frequencies.  You need power to get around this, and tube power ain't cheap, even used.

I thought it was a resistive load, if its capacitive its bad news to any amp.

[BobRex]

I thought it was a resistive load, if its capacitive its bad news to any amp.

This is from Jeff Dorgay's review:
"Building on the success of the Aerius, the Aerius i came out in 1996 and remained in production until 2000. The i featured an improved crossover network, which lowered the critical crossover frequency from 500hz to 450hz and allowed the ESL panel handle more of the critical midrange frequencies. The new model was an improvement in every way, but did feature a lower minimum impedance (2 ohms with the Aerius; 1.7 ohms with the Aerius i) that made them tougher to drive with low-powered tube amplifiers.

Performance the modestly powered tube amplifiers at my disposal was mixed. The CJ MV-50 and PrimaLuna Dialog 4 with EL34 output tubes (and about 35-45 watts per channel) had no problem driving the Aerius i, yet the vintage Dynaco Stereo 70 struggled, offering boomy and uncontrolled bass as well as a rolled-off high end. Note to tube aficionados: Make certain you can audition the speakers with your amplifier; the more power, the better and if your amplifier offers a 2-ohm tap, that will help.

While these speakers work well with most tube amplification, I’ve always achieved the best balance of musicality, HF extension, and bass control with a vacuum-tube preamplifier and high-current solid-state power amplifier."

As the impedance of the panels drops, the capacitance increases, so low impedance, high capacitive reactance.

[FullRangeMan]

This is from Jeff Dorgay's review:
"Building on the success of the Aerius, the Aerius i came out in 1996 and remained in production until 2000. The i featured an improved crossover network, which lowered the critical crossover frequency from 500hz to 450hz and allowed the ESL panel handle more of the critical midrange frequencies. The new model was an improvement in every way, but did feature a lower minimum impedance (2 ohms with the Aerius; 1.7 ohms with the Aerius i) that made them tougher to drive with low-powered tube amplifiers.

Performance the modestly powered tube amplifiers at my disposal was mixed. The CJ MV-50 and PrimaLuna Dialog 4 with EL34 output tubes (and about 35-45 watts per channel) had no problem driving the Aerius i, yet the vintage Dynaco Stereo 70 struggled, offering boomy and uncontrolled bass as well as a rolled-off high end. Note to tube aficionados: Make certain you can audition the speakers with your amplifier; the more power, the better and if your amplifier offers a 2-ohm tap, that will help.

While these speakers work well with most tube amplification, I’ve always achieved the best balance of musicality, HF extension, and bass control with a vacuum-tube preamplifier and high-current solid-state power amplifier."

As the impedance of the panels drops, the capacitance increases, so low impedance, high capacitive reactance.

Yep its capacitive and reactive, I surprised as it have a big transformer in the xover as most ES speaker. I listened this ML just once in 90s at a dealer, I was not impressed why the soundstage were similar to a cone loudspeaker, not 3D as my Carver Amazing.
The harmonics and panel resonances from this ML was not according the human brain expect to form the sound image.

[weatherman1]

Hybrid Vincent SV236mk produces 10 wpc Class A, 150wpc @8 ohm, 250 wpc @4ohm.  I bought one used for under $1000 to drive ML Montis because the KT88 amp I had didn't have enough umph.  Aerius are tough on any system because of that really low load in the upper harmonic range and even harder if you listen at high volume but are excellent sounding with a beefy watt supply.  Try this review http://www.stereophile.com/integratedamps/vincent_tubeline_sv-236mk_integrated_amplifier/#AHGGs5vBZv8xXmpf.97.  You can roll different pre-amp valves, plenty of power, and price and build quality are excellent.  Might find one at that $700 level.  Happy hunting!

[twitch54]

I have a friend looking for an integrated tube amplifier to connect to a pair of Martin Logan Aerius loudspeakers. Can he find joy for under $700?

no joy at that price point ............ the likelihood of amp at that price point not rolling off the high freq is rare if not impossible, not to mention little to no control over the bass.

[Wayner]

We are also forgetting one thing, most MLs impedance level at some frequencies can go down to an ohm or 2. My reQuests can. This presents an interesting load problem to solid state amps for sure, but a tube amp may not like that load at all. The one option (if the amp has different loadings for speaker outputs (4, 8 and 16 for instance)), is to use the 4 ohm taps. The power output will go down, but the amp might be happier.

Overall. like twitch has suggested, probably not a good mating pair and certainly not at that price point.

On a side note, if you are looking for that "tube" sound, how about a tube buffer stage routed thru/between your amp and preamp. It might give you the softness of the tube sound you are looking for, while remaining solid state.....

Just an idea....

'ner

[twitch54]

and to further Wayner's idea, I for years when I owned my M/L Spire's (hybrid , so easier to drive with their powered bass drivers) drove them with a pair of Rogue Audio M-180 mono blocks. Great bandwidth which yielded super control of the stat panel. As for the extreme dip in the impedance, it's way up top (very little music content) and anybody like me (over 60) couldn't hear anything up there anyways !! ...LOL

Dave