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  3. 161353-98013

Pass Labs x250.8 vs tube amps

I have a beautiful system. Lumin X1 > BAT Rex 2 pre > Pass Labs x250.8> Sound Labs M545 (ESL) in a tiny room (9x 11 ft).  This system has the most glorious SQ: smooth, detailed and powerful , along with great bass. I would say this sound equals or betters any ultra high end system. HOWEVER, I have a problem. My system takes 6 hours of music playing to sound this good. I had X250.5 and I had the same issue. Leaving it on idle overnight doesn’t solve the problem. It is 15 W class A, so it generates quite a bit of heat, and yet I have to still play music. Because my room is small, I don’t crank up too much- maybe this is the problem, but the temperature doesn’t complete stabilize for 5-6 hours. The top reaches 107 deg in 2 hours, but the front plate doesn’t reach 107 until the 6 th hr when it starts to sound glorious. I have never had a tube amp and I am wondering if I can reach that thermal equilibrium and the glorious SQ faster with a tube amp? I worried about the heat generation with a tube amp in this small room, but X250.8 generates 450 W just idling. This is no worse than tube amps like Audio Research 150 Se, which I demo’d and was impressed by. BTW, I need power in the amp because of the esl speakers.
What do you all think?

128x128chungjh
ozzy's avatar
ozzy
7,502 posts
 
I own the Lumin X1, fantastic unit!
I also owned a Pass Labs X350.5 and also demoed the X350.8.
In the end, I preferred the Carver M350 tube Mono Blocks. To me, it is much more musical, open and with greater dynamics. Hard to believe a tube amp can be this dynamic.

I also eliminated the preamp and started running my Lumin X1 direct to the Carver Amps. Best of all possible worlds.

BTW, I don’t think the Carvers put out as much heat as the Pass Labs did. And they seem ready to go soon after turn on.

ozzy
chungjh's avatar
chungjh OP
265 posts
 
@ozzy 

I tried going direct from Lumin X1 to X250.8 and it never sounded as good as inserting BAT rex2 preamp between them. May be it is the tube goodness. If M350 really works for me, I can save a bundle of $. Can you tell me how you like M350? How about reliability, service from Carver?
arcticdeth's avatar
arcticdeth
1,572 posts
 
8 pm til next morning is more than enough warm up.
     Is there another issue. Just on idle should be fine for warm up.

 Mine go on about 8-9 pm, stay idle til 6 am or til I start listening.
   Sure it may take 15 min maybe to sound better, but that’s subjective.

  
chungjh's avatar
chungjh OP
265 posts
 
@arcticdeth

Which amp do you have?
ozzy's avatar
ozzy
7,502 posts
 
chungjh,
Carver claims that his design makes the tubes run cooler and the tubes should last longer. I think his claim is something like 20 years. But, that is hard to believe.
Bob Carver has always been easy to contact, heck he even flew to my house when I was demoing his speakers. (I didn't like the speakers by the way).
The Lumin X1 with the new Leedh volume control direct to the amps is definatly the way to go.

ozzy
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