Tube Amp recommendation for Thiel CS1.6 under $2k

I have the Thiel 3.6's and their low sensitivity and low 2.5 to 3 ohm impedance makes it a challenge for a tube amp -- but the one saving grace is the impedance is flat throughout most of the frequency range. Tough to find an excellent high power tube amp with speaker protection without spending a fortune.

I ended up designing and building my own tube amp using the KT150 tube in ultralinear and triode. For speaker protection, I used a circuit breaker power switch tripped by high plate current from tube failure, loss of fixed bias or speaker terminal short, plus a time delay heater warm up.  I had a custom single tap 3-ohm output transformer rated at 70 watts (down to 27hz) wound by Jack Elliano at ElectraPrint. The amp uses balanced inputs only, with no phase splitters -- just a pair of 6SL7 mu-followers to swing the signal to the output tubes. Works extremely well with the 3.6's doing a decent job at the low frequencies and the overall dynamics preserved. I still use the Mark Levinsons when power is called for but for a lot of softer music the 60 watt KT150's fit the bill much much better

My experience with Thiel’s, is they need power, and if not they can sound cold and light. Aerial Acoustics speakers are the same; they need a big amp to open up. I’d look for the biggest solid state amp you can afford… that has quality. I’d say look for a Pass X250 but I don’t think you will find one for $2K. Parasound A21 might be a nice amp. 

uthlidian

Feel free to join us over on Thiel Owners thread. There are a few fans and owners of model CS 1.6 speakers on The Panel.

Happy Listening!

gs5556

Feel free to join us over on Thiel Owners thread. There are several fans and owners of model 3.6 loudspeakers on The Panel.

Happy Listening!

For low impedance loudspeakers there is only one tube power amp I would suggest: the Music Reference RM-200 Mk.2. The amp was designed specifically for low impedance loads, a job at which it excels. Do a Google search and read all about it. Reviewed by Michael Fremer in Stereophile (in both original and Mk.2 iterations), residing in the mag’s Recommended Components list Class A Tube Amp category for many years.

I don’t know what you mean by "vintage", but the RM-200 was introduced in 1998, the Mk.2 version a little over a decade later. It typically sells used (of course) for around $3000, a real bargain. I’ve owned ARC, Atma-Sphere, and Music Reference tube power amps, and have settled on MR for my remaining years. They’re all great, but for low impedance loads the RM-200 is the one to go with. IMO, of course.

Power output is 100 watts, and from just a single pair of KT88 or 6550 tubes per channel! The Atma-Sphere M-60, in contrast, uses 8 output tubes (16 for a stereo pair) to produce only 60 watts, and is not well suited to low impedance loads.

$3000 is 50% more than your $2000 budget, but $2000 is unfortunately just not doable. Save up, or sell something else!