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Suggestions please!! --Need to replace vintage Audio Research VT 200 Tube Power Amp

I have a nearly 25 year old ARC VT200 amp, which just arc'd out on me for the 3rd time in 18 months, and I have decided I cannot sink any more money or aggravation into this amp. I purchased it used about 7 years ago, and it had just been re-tubed, and it ran problem free for me for over 5 years. Then without warning it arc'd out, resulting in a replacement of all tubes, capacitors, etc.  10 months later, the same thing happened again.  I nearly bailed on it then, but the repair shop assured me that they could "really fix it" this time, blaming the repeat issue on the need to replace all of the tube sockets and repair some thinning wiring, and they assured me it would be "like new" and should run problem free for years to come.  It's been 9 months, and it's been running fine with relatively light use (probably 300 hours since the repair) and last night the fireworks happened again. Needless to say, I've now reached the end of the road with this amp. 
So my questions are these--as much as I loved the amp (when it was working!) a comparable new ARC tube amp (which appears to be in the $15k+ range) is out of my price range. The VT 200 is currently paired with an ARC Reference 2 preamp and a tube ARC phono stage from the same era, which are working fine, and they are driving a massive pair of ProAc Response Four speakers. I listen almost exclusively to vinyl on a VPI turntable. Does anyone have a suggestion for a new power amp for under $10K (after this experience I am reluctant to go the used route)? Also, would it be OK to pair a solid state amp with these tube components, and if so, any recommendations?  Thanks!!
karmicg
elliottbnewcombjr
5,373 posts
 
unless you are playing in a church or auditorium, those speakers, no way do you need that much power, they are 89 spl efficient, and 8 ohms.

https://www.stereophile.com/content/proac-response-4-loudspeaker-specifications

I would say 75wpc is plenty, perhaps even a bit less.

Do you have a friend with a low powered tube set, i.e. 35wpc? just try that, to establish a comfortable minimum, you will be surprised. New or used, just make sure you can return what you try.
charles1dad's avatar
charles1dad
10,250 posts
 
In the Stereophile link provided the actual measured sensitivity was 85.5 db. This is relatively low sensitivity.
erik_squires
16,056 posts
 
If you liked old ARC gear, Pass is not a bad option at all.

I'd suggest you compare it to Ayre and Luxman before choosing though.
twoleftears's avatar
twoleftears
5,318 posts
 

Aesthetix or Raven.  Both excellent choices.

BTW for many years I ran Response 2.5's with a 13W SET from Cary.

bifwynne
2,206 posts
 
Charles1dad is correct.  JA measured the Proacs sensitivity to be 85.5db.  JA wrote: "The speaker's sensitivity on the HF axis (measured using B-weighted noise) was somewhat lower than specified, at 85.5dB/W/m vs 89dB/W/m."  In my opinion, I would err on the side of more power, … not less. 

And Adg101 makes an excellent point about "care and feeding" of the VT-200.  If true, it appears that the VT-200 is a pain in the butt to bias.  I surmise that blown bias resisters may be a major operation to replace if a power tube arcs, … and arcing power tubes just go with the territory.

The innards of my Ref 150SE are wide open.  So if a bias resister blows, I don't need a neurosurgeon to replace it.  And I check the bias on my power tubes once a month, ... an easy job.  Bias drifts and that is also part of the care and feeding that goes with older ARC amps.  That said, I understand that new ARC Ref 140 is self-biasing and has a resettable circuit breaker if a KT-150 arcs.  Very nice but very expensive.   

I am sure you will make a good and practical decision.  I don't know your budget, and that should have been the first question, but if you like ARC tube amps and have the budget, give a thought to the Ref 150SE.  It has (I) a very robust power supply (1040 joules), (ii) can easily push out 150 watts into an 8 ohm load off the 8 ohm taps, and (iii) has a relatively low output impedance for a tube amp (approx. 6 ohms  off the 8 amp taps and even lower off the 4 ohm taps).  

Good luck and stay safe.

BIF
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