Tube guy gets a B&K: tubes vs solid state


You folks probably already know all this, but maybe these observations will be helpful for some newbie... (tubey newbie?).

I've been looking to understand how to improve the sound of my tube system and decided to try a SS amp as a point of reference, and potentially as a permanent switch. Thanks to many here, the desirable choice seemed to be a McCormack DNA. But being unsure I decided to take a cheaper approach and bought a B&K ST-140 ($202 on ebay + $27 shipping), version 2, toroidal transformer. It is like new. After swapping back and forth with my Marantz 8B I have the following observations. Rest of system is stock CJ PV-5, ProAc One SCs, ordinary car audio speaker cable (next upgrade), all Kimber PBJ interconnects.

The issues I have with my system are a desire for tighter bass, more openness, less of a congested presentation. I got my system in 95 or so, and did some comparisons to SS then, but sometimes you have to relearn old lessons.

1) I am amazed at how pretty and smooth a sound the B&K has. It is a "lighter" sound, more even and polite or reserved, and the various instruments don't seem to be congesting together. For a $200, 20 year old amp, it is quite amazing.

2) The sound of tubes is different from the sound of solid state. It's difficult to overstate the significance of this. The tube sound is palpable and dimensional. I knew this before, and these have to be the most commonly used terms but it's true. But it's a bit stunning to hear it again.

3) I would never be happy with solid state because no matter how pretty, it does not have this tangible substance, palbability, or dimensionality. It is key to enjoyment of the sound. It is sonic sculpture versus sonic painting.

4) I expected the bass to be deeper, larger, and tighter with the B&K. At first blush I thought it was. But after several comparisons, it is none of these. It is stronger and...tighter doesn't seem like the right word but it is as tight with the 8B. More importantly it is more real, because of the palpability, and that makes it sound more accurate or defined. On recordings with fuzzy bass, though, I think the even, clear, laid-back presentation of the B&K renders the bass with more seeming definition whereas the 8B seems to be trying to make it full and tangible but having nothing to work with, it just puts forth a kinda warm and soft bassiness.

5) I now believe the comment I read here, that a SS amp with a tube preamp will not give the dimensionality and palpability of tubes. One needs a tube amp for this.

I no longer feel I need tighter bass; I see it differently and very much like the bass I have with the 8B. I do think I could use more openness, a bit better high end (PV-5s, I'm told here, have rolled-off highs), and a less congested sound when the band gets busy, which somehow seems to be linked to the palpability or substance of the sound. It's like the thick palpability is a bit too thick and things get congested together.

I'm not sure whether changes to the amp or preamp will solve those, but the experience with the B&K suggests the next move is the preamp. I'm trying to decide whether to pick up something less romantic/lush like an ARC or VTL, or to send my PV-5 off for upgrades, or buy a newer CJ. At this point not knowing which will be the more effective it's a coin toss unless a killer deal comes along. I'm getting more reluctant though to alter the nature of my PV-5. Since getting back into hifi I have never seen one for sale.

Any suggestions or thoughts on my next move would be most welcome.

Jim
river251

Showing 1 response by counterbiz

Hi, first time posting here. I have Luxman MB 3045 mono blocks with 6lf6 output tubes, bone stock configuration. After owning many many solid state setups, this pair fell into my lap at a price I couldn't refuse. I had to claim complete ignorance to anything with tubes. I actually stayed away from the idea of tubes since I had no experience whatsoever. I had heard many extol the superiority of the "tube sound", but had no frame of reference.

After receiving this pair, two friends came over with their tube amps (Mcintosh MC275 & Dynaco ST120 modded. They cycled their gear one by one with my Pioneer Spec 1 pre, Infinity Kappa 9's & we tore up some half speed masters/mobile fidelity vinyl on a VPI turntable. It was a fairly long session lasting six hours plus, much to the frustration of my wife.

After all these years I was converted. What joy to my ears. I had never been able to listen that long without the familiar fatigue we encounter so often. I did however experience a lack of what I will refer to as "tight accurate bass". My opinion after experimentation is this: Solid state is great for the low end. I have since bi-amped my system using the tubes on the highs & mids combined with my Spec 2 on the bottom. Obviously the Kappa's are bi-amp capable.

One caveat, the Kappa's work the Spec pretty hard. I am in the process of re-capping/restoring a pair of Bose 1801 power amps, which I plan to cycle in one of them on the bottom. (They can be wired to mono block configuration, but alas not stable with anything besides an 8 ohm speaker load. As most of us know, the Kappa's dip much much deeper into the abyss. I do believe one of them will perform much better than the Spec 2 since it is more of a high current design. I re-capped using a pair of 47000mf 100v output filter caps, which may prove to give me the reserve headroom that the Kappa's will require.

My previous amplification was a re-capped Carver M1.5t with a fair amount of power and current, but still had to be reserved with the Kappa's. They are wonderful speakers but hazardous to a majority of gear. They have an extended bass mode switch linked to the Xovers that make them dip even lower. I clipped the Carver one time and never used it again.

Sorry for the rater long diatribe, I just wanted to weigh in and comment on a worthy compromise of blending what I consider the best of both worlds. I am currently content with the obvious improvement in the bass until I finish the 1801's this week. One improvement on the near horizon will be a competent tube based pre-amp. For now I am filtering my digital library through a Music Hall 25.3 DAC with a tube buffer output with tangible positive results.

Most of us don't have deep enough pockets to approach this hobby with no limitation on obtaining what we would really like to have. I feel like I have been extremely fortunate considering the level of sound quality I enjoy compared the the modest resources invested. I suppose for those who can afford high powered tube amplification, the bass would perhaps not be an issue. I would love to be able to test this theory, but alas there is reality.

In summary, if you have tube amplification & speakers you love with bi-amp option, do not hesitate to put in a beefy solid state amp on the bottom. IMHO, it is the best combination out there.