Tube / SS bi-amping

What are peoples thoughts regarding mixing SS and tubes when it comes to bi-amping? I was thinking about using a tube amp for the panel section and a more powerful SS amp for the bass section. Is this a good idea or will it just sound bad? Is or has anyone done this?

Thanks

Cherian

Cherian,

A lot have done this. SS for the bass and tubes for the panels. I think this is why the new series of powered ESLs are great.

Not only do people do this for MLs, but I know several audiophiles who have done the same biamp configuration to their Innersound electrostatic hybrid speakers.

You need to pm Spike.

I have done this with great results on my Ascents. I had the CJ 140 tube amp hooked up to them and the sound was great. But then I put Outlaw Audio 200 wpc monoblocs on the woofers and the sound got so much better I was astounded. Not only did the lower registers improve tremendously, but the mids and highs coming from the panel were clearer and more liquid than I had ever heard them. Freeing the tube amp of woofer duty really brought the entire sound spectrum up to a whole new level. I highly recommend you try it out. Just be careful that the gain on your amps is the same or very close, so that you don't get a mismatch; otherwise you would have to get an in-line attenuator to match them back up.

Cherian,

I joined this site to learn more about bi-amping. JonFo is another guy that could give some more insight if you want to try active bi-amping with an external cross-over.

But passively bi-amping could be a nice upgrade. As Rich pointed out, the SS amp has just one job-power the woofers. Then the tube amp deals with the panels. Down the line, I would like to give this shot just for kicks. Everyone has different impressions with tube amps; some love 'em, while others might say the higher frequences are rolled off a bit. Again, it's all subjective.

No, I don't think this is a bad idea at all. Many, many audio enthusiasts employ mulitple amps to drive various woofers, or panels.

Erik

You rang?

1st, you can do a search with here with biamp, tube, spike as keywords and you'll be able to see a bunch of posts on this subject. As with any other subject in audio, there are 2 camps on this subject and I happen to be on the pro-biamp side. At the crux of the problem is the internal crossover of the older Logans which cannot be easily bypassed. It could be done if you're comfortable with a soldering iron as JonFo has posted in the tweak section and that is the correct way of implementing bi-amp. For myself, I compromised by going the passive way with tubes on the panels and solid-state on the bass. Even as a compromise, I get very good results with my set-up.

Spike

So what I got from this thread....

Biamping has two methods:

A - Biamp passively; leave internal xo alone. A bit of a compromise, but no soldering required.

B - Biamp "actively"; remove internal xo from the line. Soldering and some JonFo-ish knowledge required.

I hope I got it.

Thanks everyone for the input. I'm in the process of looking for a nice used CJ MV60SE tube amp. For a start I will stick with the ML internal crossover.

Cherian's gone tube crazy.... first the preamp.... now an amp for the panels.

Why not give it a try using your current gear

I went back and noticed that you have a full set of Monarchy SM70 and 100 at your fingertips literally. From what I've heard, the SM70 Pro is close to single ended tube amplifier sonically speaking. I would try hooking up the SM70 Pro monoblocs on the panels and the 100 driving pulling bass duties to see how you like that bi-amp configuration.

Happy listenning
Spike

Spike,

This is a very good idea thanks. I will give this a try. Now why did I not think of this.

Thanks

Cherian

Opinions from the other camp...

To give the other camp a fair chance, here's the thread on AA "Is it better to bi-amp or to use 1 larger amp". I can see the rationale against bi-amping due to coherency, but I think it really depends on the crossover frequency. In my case of the ReQuest where the crossover point is low at 200Hz, this issue is not noticeable. It may be a completely different story where the crossover point is smack in the midrange frequency (somewhere around the 1500Hz or higher).

Spike

Spike said:

(...) It may be a completely different story where the crossover point is smack in the midrange frequency (somewhere around the 1500Hz or higher).

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I would think anything above 250 Hz would be midrange, given that Concert A is 440 Hz and middle C is 278 Hz.

In fact, this is precisely one of the things that are making me think of moving away from Vantages to something that doesn't have the integration grey area exactly where most music occurs.

paulo m said:

I would think anything above 250 Hz would be midrange, given that Concert A is 440 Hz and middle C is 278 Hz.

In fact, this is precisely one of the things that are making me think of moving away from Vantages to something that doesn't have the integration grey area exactly where most music occurs.

Click to expand...

Which is the original rationale for the panel size on the Monolith - crossover could then be at 120 Hz second order. I am not suggesting that the Monolith is the equal of the modern speakers but it is correctly aligned i.e. vertical and the crossover is at a point which maximises the advantages of a single driver covering most of the musical range. ML seemed to keep stepping away from this philosophy with later efforts. I suspect this is to do with the viability of selling big speakers.

I think Spike's observation regarding crossover frequency and amplifier tonal integration (coherency) is right on the money.

I think that succesful passive biamping is a lot trickier than is intimated by the multitude of posts on forums. It is often difficult to match the gain of amplifiers with reasonable input impedance of both the amplifiers - input impedance can be significantly different between ss and valve amps. The preamp needs to be of sufficient quality to cope with this. Phase shifts, polarity issues, extra runs of cable, potentially an attenuator on one of the amps - the argument for a higher quality single amp becomes compelling.

If you want valves put them in the preamp.

Waiting, waiting for the CLX

Kevin

kwr said:

Waiting, waiting for the CLX

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Hear, hear!

(although I should add I will soon listen to the bigger Analysis Audio models and if that plainly rocks my socks off I will--sorry to say--happily and merrily defect the ML camp ... The impedance curve of those speakers is just too juicy to pass unnoticed, making them extremely easy to drive. If it has the incredible sound of the bigger Apogees, then I'll be on the next boat off to ribbon-land)

Not so fast...

Paulo,
If you're objecting to the 400Hz crossover of the Vantage, why go to the 650Hz crossover of the Analysis Audio? While we're on the subject of planar magnetic design, what differentiates Analysis from...Magnepan beside the price of admission? Sorry, I just gotta ask the obvious Sure, the Analysis may look like Apogee but they are NOT all ribbons like the Apogee. That may explain why the impedance curve is...so juicy!

Spike

Spike said:

Paulo,
If you're objecting to the 400Hz crossover of the Vantage, why go to the 650Hz crossover of the Analysis Audio?

Click to expand...

My contention with the Vantage is that both regions of the spectrum have substantially different technologies driving them (definition and scope of "substantially different" entirely up to you). There is, on occasion, a certain "plasticky" character to the sound that I am, perhaps incorrectly, attributing to an eventual integration issue; or it might just be the MartinLogan sound. Perhaps if I tried the Summits in my room I would get some closure on this issue.

Spike said:

While we're on the subject of planar magnetic design, what differentiates Analysis from...Magnepan beside the price of admission? Sorry, I just gotta ask the obvious Sure, the Analysis may look like Apogee but they are NOT all ribbons like the Apogee. That may explain why the impedance curve is...so juicy!

Click to expand...

I know the Analysis are not strictly a copy of the Apogee, but the visual similarity has elicited that comparison. Apparently, some people also find their sound similar.

For me, they are another contender in the planar world, now that I ruled out the Magnepans--heard the 20.1Rs a week ago and liked what was there to like: lifelike size, big soundstage, very natural sounding midrange with good amplification (ARC Ref 210s + Ref 3), but only after the HF filter was applied; the utter lack of bass was disappointing, and the need to add a pair of subwoofers to get the whole sound seemed like cheating.

My ears will judge how the Analysis compare against everything else I've been listening to, and since I do like the sound of ribbons, I am very curious to hear how they perform, especially with their driving ease.

I have SoundLabs on my list too, but that audition will have to wait a month or two.