Benefits of a SS amp with a Tube Pre

ZMan · « **on:** 6 May 2004, 08:11 pm »

I currently run a Thor TA-2000 Pre and a Tube power amp. I want to explore the possiblity of replacing the tube power amp with a 250-350 watt SS power amp (Speakers VMPS RM 2 Neo's).

What advantages/disadvantages would there be in the marriage of a Tube pre and SS power amp in terms of midrange, treble and soundstage production??

Would the combination soften the downside characteristics of SS amps?

Would rolling the pre-amp tubes provide opportunities in customizing the sound?

Thanks,
Ed

maxwalrath · « **Reply #1 on:** 6 May 2004, 08:25 pm »

Tubes in the preamp section have worked well for me. I got a happy medium of a powerful bass and dynamic response without the negatives people usually attribute to SS. In a system with a tube pre, changing tubes can make a world of difference. Tailoring the system to your taste through tube rolling is definitely possible.

I've had two different Jolida tube pre SS power amp integrateds, used the ee minimax with the Van Alstine 240 power amp and the odyssey stratos, and the Modwright beta pre with the stratos. I preferred every one of these setups to the all SS systems I had.

Tonto Yoder · « **Reply #2 on:** 6 May 2004, 08:48 pm »

Zman,
are you contemplating a local purchase?? If so, you might schlep your preamp into House of High Fidelity and try out their McIntosh amps?? They did have that Millenium edition (tubed) and they have solid state powerhouses as well (in the home theater set-up). Might be a good time of year to audition this way since business must have tapered down a bit: I doubt that Sound Advice would allow such auditioning with their Krell stuff.
As Max said above, the conventional thinking is that bass would be tighter and better controlled with the SS amp.

John Casler · « **Reply #3 on:** 6 May 2004, 09:11 pm »

Quote from: ZMan

I currently run a Thor TA-2000 Pre and a Tube power amp. I want to explore the possiblity of replacing the tube power amp with a 250-350 watt SS power amp (Speakers VMPS RM 2 Neo's).

What advantages/disadvantages would there be in the marriage of a Tube pre and SS power amp in terms of midrange, treble and soundstage production??

Would the combination soften the downside characteristics of SS amps?

Would rolling the pre-amp tubes provide opportunities in customizing the sound?

Thanks,
Ed

I run both the EE MiniMax CDP and the MiniMax Preamp (both tube) to my SS CineNova power amp and then to VMPS speakers and find it a very good match.

Tube rolling "certainly" is needed to get the best overall result, but once it is dialed in, it is pretty sweet.

warnerwh · « **Reply #4 on:** 6 May 2004, 09:13 pm »

I went through several dacs looking for a certain quality but couldn't find. Then I bought an ARC LS 16 and it was a bullseye. With my Parasound amp it's exactly what I had been looking(listening) for. My preferance is to have a first class bass so a tube amp was out. Thought a dac was what I needed but that was wrong too. It's a match made in heaven. Also having at least 200wpc and good current capability was important to me, another good point for the SS amp. The tube pre really smoothes things out and the ARC units aren't know for being overly tubey. If you get a used amp then you have nothing to lose. Also the extra power will surprise you if you turn it up much. I also own VMPS speakers and they like the power, less than 200wpc can make the bass mushy if you push it at all. I"ve got a feeling you're going to wish you tried it sooner.

funkytabla · « **Reply #5 on:** 7 May 2004, 08:03 pm »

Many people successfully use tubed preamps with solid state amps

BTW, I'd be interested to hear whether a tubed dac would have less effect on the overall sonic signature of your system, than in comparison to using a tubed preamp?

So in terms of say smoothing off the overall sound when using a ss amp, which component would have the greatest influence? Or would it be system specific?

flintstone · « **Reply #6 on:** 7 May 2004, 09:12 pm »

I'm using a tube Audioprism Mantissa pre with my Krell Ksa-250 SS amp, these feed a Pair of Apogee Duetta Signature speakers. Added the tube pre-amp only a few days ago and am very happy with this new setup!

I had a Bent Audio TVC-102 passive in the system which sounded great but not enough volume control in my new (much larger) room as the Krell is not an ideal match for a passive pre.

Dave

warnerwh · « **Reply #7 on:** 7 May 2004, 10:57 pm »

One of the dacs I tried was a Cal Labs Alpha tube dac. This was not bad but the tube pre is much better and also had more of an effect. Also the dac I use now is the Channel Island dac. This combination is very good.

PhilNYC · « **Reply #8 on:** 7 May 2004, 11:16 pm »

Zman,

I've generally found that the difference in using a tubed pre/tubed amp combo vs. a tubed pre/ss amp is less about the specifics in midrange, treble, and soundstage, and much more about the overall texture and harmonic richness of the sound as well as the "tightness" of bass. As a dealer, I get to meet and speak with a lot of audiophiles, and in almost all cases, the discussions regarding tubes vs. solid state revolve around a spectrum of tubes/lush <----> ss/tight. Of course, there are exceptions to everything, but I do feel that your question is simply a matter of discovering the degree to which going to a solid state amp will move you from "lush" towards "tight". How far your system will go depends on the specific preamp and amp, as well as the synergy with the rest of your system.

From a technical viewpoint, I forgot the details of why, but I've heard from more than one manufacturer that tubes behave in a manner that is very suitable for preamps and amp input stages, and solid state behaves in a manner that is very suitable for amps. If you look at the majority of hybrid components out there, you can look at how/where they implement tubes or solid state and conclude that those manufacturers are trying to design components that use the best characteristics of each...and they usually do it as I've described here. So you might even conclude that it's not even so much about how each type of component adds a certain character to the sound, and it's more that the appropriate technology is being used to its best advantage in the case of a tubed pre and ss amp.

AKSA · « **Reply #9 on:** 8 May 2004, 03:34 am »

High end is like motorcycles:

Good SS is an inline four with balance shafts.

Good tube stuff is a V twin WITHOUT balance shafts.

It's all in the texture.......

Hugh

WEEZ · « **Reply #10 on:** 8 May 2004, 01:52 pm »

It has usually been the case, that vacuum tubes do a better job at amplifying low level signals (at the voltage stage). Hence their common use in phono pre-amps; cd player outputs; pre-amps, etc.

Vacuum tubes can have a more difficult time with high level current and more difficult loads (loudspeakers)- so many use solid state for driving speakers. Phil hit the nail on the head. That's why a speaker should have a 'flat' impedence plot if you use a vacuum tube amplifier.

I agree with Hugh's analogy- if one is talking about amplifiers. However, with pre-amps, sometimes the "little bottles" just do the harmonics better.

Today, both technologies have come to sound more similar in the better designs than in years past. Having said that; a tube pre and a ss power can really sound special, though.

WEEZ

Val · « **Reply #11 on:** 8 May 2004, 02:56 pm »

Don't go crazy with the hope of nirvana without first checking a basic compatibility, preamp output impedance and power amp input impedance. I recently read a 6moons rave review of a power amp with a 1kOhm input impedance. The author doesn't say anything about this abnormally low number, which would be an impossible load for your typical tube preamp. MGD makes exactly this point in his BFS review of the deHavilland UltraVerve. A great preamp no doubt, but better at handling input impedances higher than 20kOhms. To their credit, deHavilland recommend loadings upwards of 10kOhms for their preamps.

Val

warnerwh · « **Reply #12 on:** 8 May 2004, 06:53 pm »

Good point on the input impedance. ARC recommends a minimum of 40k on the LS 16. That cut out alot of possiblities for me in the SS amp world.

WEEZ · « **Reply #13 on:** 8 May 2004, 09:37 pm »

Good points..

A factor of 40 should be okay in most cases if the connection isn't too long. (i.e. 500 should see 20k; 1000 should see 40k, etc.) Much less than a factor of 40 could lead to frequency response rolloffs.

(I learned that the hard way years ago)

WEEZ

DTB300 · « **Reply #14 on:** 10 May 2004, 01:28 pm »

Quote from: ZMan

What advantages/disadvantages would there be in the marriage of a Tube pre and SS power amp in terms of midrange, treble and soundstage production??

I had run a Counterpoint PreAmp for many years until it finally had its day and I did not want to have it fixed anymore. So off to my local Stereo Store to pick up some demo units to try at home. I run 4 SS Amps to my Martin Logan speakers in Bi-Amp mode. I had a budget of 1000 - 1500 so the wife did not kick me out of the house

I had heard and read some good things about the Adcom SS PreAmp (GFP-750) and it was in my price range (1200-1400). While I was at the store talking to the sales person, they suggested that I also audition the ARC SP-16L (I do not run Vinyl). While out of my price range, I thought, what the heck, and brought it home too.

Both of the units were demo units and according to the SR, had many hours on them, so they were broken in. I started out hooking up the Adcom and proceeded to listen for a bit. I demo'ed in passive and active mode and found the passive to be much better. The Adcom sounded pretty good for a SS PreAmp especially with RedBook, SACD, and DVD-A as my playback medium. After a few hours of listening, it was time to put the ARC into place. Well, to make a long story short, the Adcom never got back into the system.

To answer your question on the sound. The sound was SO MUCH better in all aspects of the music - soundstage, detail, etc. etc. Midrange and female vocals were just amazing. Treble lost that zing and phzzzz, but was very much there and detailed. The bass was excellent (I also run a dedicated SS Amp for my Sub and a crossover for the sub) What I heard overall was how the recording sounded. Good CD's sounded good, bad CD's sounded bad, and excellent CD's sounded excellent. What we are all searching for in playback.

I lived with another Tube PreAmp for so long, that I wondered what a SS Pre would sound like, and I found out. Now bear in mind I did not give any other SS Pre's a try, as I was immediately sold on the ARC and the sound I was getting. Yes, it did cost me out of my range of money, but the wife understood after listening herself.

One other thing, with Tube Pre's you will not need to change tubes that often, and with ARC, they sell the matched tubes for the units they run, instead of having to search for a good Tube Seller. The 4 Tubes for the ARC cost around $80 and they also sell tube dampeners for their tubes.

Overall, see if you can get some demo units to try out and see how they sound. I think you will like the sound you get with the Tube Pre and the SS Amps - I know I did.

Later....Dan

warnerwh · « **Reply #15 on:** 11 May 2004, 12:56 am »

" The sound was SO MUCH better in all aspects of the music - soundstage, detail, etc. etc. Midrange and female vocals were just amazing. Treble lost that zing and phzzzz, but was very much there and detailed."

That was my impression too. That's why I said in an earlier post he may have wished he tried a tube preamp a long time ago. I know I should have but was so unfamiliar with tube gear and the fact it had been overly expensive for me that it took years for all the reading I've done about tube gear to sink into my little head. The tube preamp made all the difference and it's far from being mushy or syrupy. The bass is excellent on the behemoths with four 15's and two 10's, tight and solid. Vocals are rich and smooth and the treble sounds more real. A huge step up from the Krell I was using.