Amp Recommendations for Acoustat 1+1s


Hi all,

I juat scored a beautiful pair of Acoustat 1+1s in an auction last week (thanks AudiogoN!) and am looking for a suitable amp.

First, I have to tell you about the Acoustats. They were one of the last 3 pairs of 1+1/2+2s that Acoustat made. The owner was a friend of the folks at Windham Hill Records who were friends of Jim Strickland. They asked him to make three more pair for their personal use. Mine are in MINT condition with beautiful rosewood bases and brand new black socks ordered from Italy. They also have the latest "red" medallion transformers. I'm just smitten...Can you tell?

Anyway, I'm currently driving them with an Adcom GFA-555II and it sounds great, but I know that I could do better. I also know that the Acoustats are famously difficult to drive. That being said, I hear of people recommending everything from moderately powered tube amps to high current monoblocks. Do they need current (solid state) or voltage (tubes)?

I should also mention that my room is quite large. It's 25'X35'. The Adcom doesn't seem to have any problem driving them to concert levels and the "clipping" indicators on the front of the amp never so much as flicker. The amp also doesn't get particularly hot - although it does get warm.

I was thinking about finding an Acoustat TNT-200 since I know that it was designed specifically for the Acoustats.

So, what would you recommend (less than $1,000...the cheaper the better!) to extract the best from these speakers?

I appreciate your collective assistance.
gullahisland
Consider the Adcom GFA-5802 at about $875 used on Audiogon. I never tried it on the 1+1, but experimented with it for a long time on my friend's pair of Magnepan MG 1.6QRs. The 1.6QRs are very hard to drive, but the 5802 drove them very well and delivered a non-fatiguing, rather musical sound with relatively low coloration.

The low power Krell KSA-50 will not work. I tried the KSA-100 on the MG1.6QRs and they did not work. They are stable down to 2 ohms, but stability without the current does not solve your problem. As for a TNT, I see more potential issues buying an amp without a manufacturer to service it. Electronics are more likely to require service than speakers.
The Hafler 9505 is the updated TNT-200 and was designed by Jim Strickland. You should be able find one for less than $1000 with no trouble. I've owned both of them and the 9505 is considerably better. Drove my 2+2s easily for the past 7 years. I also own 1+1s and they take more power to drive than the 2+2s.
I use a Music Reference RM-9 tube amp (KT-88) on mine. 100wc/ch in a small/medium room. Sounds great! Use the 4 ohm tap.
I'll second Elgordo's comment on the Hafler 9505. I've used one for 7 years or so with Maggie 1.5's, 1.6's and now 3.6's. Outstanding sound IMHO and excellent durability. 250wpc @8 ohms, 375wpc @4 ohms. Rave review in S'hile in '92, including Sam Tellig, and many other publications. Now sold mainly for professional use and used in many a recording studio, since Hafler has exited the consumer market. This amp deserves more recognition.
I'm using a YBA DT on Acoustat 3s and it works extremely well. I used to use PS Model 2 Blocks in mono and they literally caught fire when I drove them hard. The Acoustats draw a lot of current and the YBA is up to the task without any hint of imaging loss and the bass is incredible.