Thinking of trying tubes...

Hello, everyone,

I've been a long time solid state guy, and I'm nowhere nere a dealer to take a listen for myself, so need some advice.

For a few years, I've used a Pass Labs X250 amplifier with a set of Dunlavy SC-IVs. I am also a guitarist, and have always used tube gear for my guitar playing--mainly a marshall for crunch and a fender twin for clean for those of you who know what they are. I have always felt that the tube sounds much more rich and present with the guitar stuff, but I know NOTHING about where to go or what to try for my audio system and would like some suggestions.

I can spend about 3500 or so and I'll go used because you get more for your audio dollar that way. Now, given what most of you know about the Pass sound, and the general relationship a powerhouse like that would have with the Dunlavys, any suggestions on where I might want to start?

If you would feel more comfortable, please feel free to email me!

Thanks all!

Ag insider logo xs@2xrnbowers
I have found in 35 years of experience that what matters is implementation and not whether a piece of gear is tube or solid state. A guitar amp is a little different in that they are usually overdriven to get the crunch.
If you really want to drive the Dunlavy's right, I would stretch your budget a little bit and get the VTL MB-450 monoblock amps. (Used they go for around $4,500, but you can sometimes talk the sellers down a little, closer to $4K.) They have lots of power to really get the most out of those speakers. (The bass response of the MB-450s is about as good as it gets for tube amps, unless you can spend double or triple the amount.) These amps sound really good, and have a nice touch of tube bloom in the mid-range. Not so much as to be considered bloated by any means, but just a nice touch. The treble is nicely extended and refined. Soundstaging and imaging is excellent as well. A true top notch tube amp in my book.

Cavaet time:
One, They run HOT. They will raise the temperature in your room several degrees, unless it is air conditioned.
Two, While they have very good bass response, (I consider it to be great bass for a tube amp), it can be bettered by equal quality solid state monoblock amps. (But then said solid state monoblocks don't have that nice mid-range either!)
Three, they have 10 tubes per monoblock amp, so retubing them can get a bit expensive, as can tube rolling. (But hey, that is what tube amps are all about, right?!)

Good Luck in your search!
I almost bought the SC IVs about ten years ago. I heard them with a CJ premier 11a and an Audio Research VT 100. If you like jazz or classical music and don't need to impress your friends with earth shaking bass or deafening volume levels tubes sound absolutely great. If you like Led Zep or the Stones at concert volume I'd be happy with the Pass and call it a day. I ended up with the 11a and a pair of B&W Signature 30's (somewhat less imposing than the SC IVs). I listen to relax and am absolutely drawn in by the combination I have...Levinson 390S for CDs, no preamp, no vinyl. Had it for over ten years, no desire to tweak or upgrade. If you listen at higher sound levels I'd probably try the Pr 12s or VT150 or 200's used.(I'm not up to speed on the Audio Research stuff, but the idea is to get 4 6550's per channel to pack the punch and still get that great midrange). I'm considering the 12s myself now that I started visiting this sight again, but I'm hoping it will pass.

Anyway, both those amps sounded great with the Dunlavy's but you wont have the control deep down or quite the dynamic range, but will have something imminently listenable, maybe more so than what you have now.

One other thought to share, I tried a Levinson 335 for a week. Listening to the Stones I could pretty much replicate the concert I'd just been to. Absolutely unbelievable sound. But interestingly at low to moderate volume levels the amps didn't sound that much different, both were clean, detailed
and involving with the CJ a tad more involving and seductive and the Levinson more controlled on the bottom end, but not by much with jazz and classical.

I opted to match the strengths of my amp and speakers with the type of music I listened to the most at the levels I listened at the most. So I took the Levinson back and never really missed it. But it was impressive!

Happy hunting.

your pass x250 is a classic. you may get a different character from tubes, but no dramatic improvements. it would be change for the sake of change.
First off, thanks to everyone who has responded, both here and through email!

The biggest question I've been asked is "what do you listen to?" The short answer is everything! I've got lots of Zepplin, but I also have a ton of things by Bach. I've got some Joe Satriani that I tend to crank, and I have everything in Karrin Allyson's catalog and can't get enough of it!

I guess when you get down to it, I want to be able to have my cake and eat it too! Lots of people have mentioned the audio research stuff to me in emails and one post here, so do you guys think a VT200 could push the big Dunlavys?

Also, one other matter worth asking about is that guitar amps aren't used in the same context as someone here very accurately stated. How much do I need to pay attention to biasing issues?

You guys are great and I greatly appreciate your help!
The starting point should be a tube pre-amp with a phone stage. If that works for you then go on to the tube amp. Call it 'baby steps'.
Look into Butler Amps at They make 150 and 250 high power hybrid tube amps for $2,300
I had the SC-IVa's a while back and ran them with VTL Deluxe 500 mono's -- a nice match. There's a pair of Deluxe 300's for sale here at $1800 obo and claimed to be in great shape. I don't think you could go wrong with those amps at that price.
I agree with Tiger, I have had a couple tubed pre's as my intial ventures into "tubedom", for around 5 or 6 years and enjoyed them with 3 different sounding SS power amps and only recently switched to an all tubed set up (SET power amp and absolutely love that). However, I have heard a tubed pre (believe it was a Hovland) with an X250 and thought it was a really great sound...and that maybe a good way to try out that "tubed" sound though, try a pre first because although I have never owned one, every time I have an oportunity to hear Pass Lab amps I always thought they were excellent to my ears. Enjoy...
Hello again.

I guess I might mention that I've used a BAT VK 5i with the system for the past 4 years. Bought it here on the Gon in 2004 and haven't regretted it. I also know that preamps don't give you the same effect as a power amp. Just isn't the same ball of wax from an electrical standpoint.

I will also mention that I have no intention of selling the Pass amp--except maybe to upgrade it to a 350. I just would like to try my hand at the tube side to see where that gets me in sonic terms. Maybe I'll find it not to my taste, but I don't believe you can say one way or another until you try.

Thanks again,
Hi Roland,
Just thought I'd throw in with Tiger and Nb_dude. You can usually find one of the cj premiers for a good price on audiogon.
The VTL 450 monoblocks was a good suggestion. I would suggest a BAT VK 75 that would mate well with your VK 5i and would be in your price range as well.