Which high power SET


I'm looking for a high power SET to drive harbeth shl5, using Shindo masseto pre amp.

Have short listed Verdier 845, Audion black shadow and Wavac MD805m. All three should drive harbeth sufficiently. Any opinions on the above 3 amps are most welcome, especially thoughts on matching with shindo pre amp.
edoit
Larryi,
Many good points you've made as usual. I agree that no single amplifier or particular topology is perfect, they all will require some degree of compromise. The key to ultimate success and long term happiness is knowing what type of sound/presentation you truly want. I stuck with the SETs since this is what Edoit expressed interest in. I believe that he's headed in a very good direction with his list of candidates.

Edoit you say that you current 30 watt amplifier is enough power and pleases you, that's important information to know. Based on that I'd strongly urge you to listen to the 845 SETs you're curious about. Given your comments it suggests that high quality 30 watts is satisfactory with your speakers. Quality will often win out over quantity with the appropriate speaker match. As Larry said an OTL is a viable option (they all sound different depending on the brand).Personally high quality SET amplifiers are the closest I've heard to mimicking the live venue experience. That's why I'm very supportive of your pursuit of them. Naturally YMMV.
Best regards,
Charles,
Edoit, I think you will find its in your best interests to do an audition on your speakers in your home if you can.

SETs with the same power as your 30-watt push-pull amp may not come off as just as refined. I alluded to the issue, but here it is in plain black and white:

If you want to really experience what an SET does, the efficiency of your speaker should be such that the amp *never* is asked to make more than about 20-25% of full power. If you follow this rule you will get the most bang for the buck out of your SET investment dollar. The reason has to do with how SETs make distortion- above that power level the higher order (harsher) distortion elements come into play. As the power demands are decreased, the distortion goes to unmeasurable and is the reason for the 'inner detail' claims you see describing a lot of SETs. This has to do with how distortion can mask detail per the ear's masking rule.

Since this speaker also has some bandwidth, you may also notice that an SET of similar power simply does not have the bass delivery, as it is very difficult to make an output transformer that can deliver bass and full treble extension at that power level.

I'm not a fan of pentode amps FWIW, being a manufacturer of triode amps myself :)

I think you have sussed out that SETs have a following for good reasons- I think if you look into it, you will find that the most successful systems have lower powered SETs (which have more bandwidth) and much more efficient loudspeakers. My speakers are 98 db 1 watt/1 meter, and I find that 30 watts is a minimum in my room, which is an average size. I do have a type 45-based amplifier (push-pull, makes about 6 watts) and it sounds better than the 45 in SET mode on the same speaker; but even so its hardly enough power to do the job!

Now for the math: the 6 watts that I have on my speaker translates to the same sound pressure level on your speaker with about 120 watts. Think about that. There is no point to buying any amplifier and then pushing it as hard as you can.
There are enough existing variables involved that a solid argument can be made for numerous opinions. Edoit's typical daily listening levels will determine so much about successful amplifier selection. We all can agree that an in home audition is the ideal solution.
I agree with Atmasphere, before writing a check for a 30 wpc SET, audition in your system. SET sounds best not pushed due to their distortion.

Larryi also has good points. Have an open mind and don't get hung up on a particular type of amp. They can all sound great but different.

I would add a higher power amp in your list and hear how your speaker can sound with more current and power. My bias is for bigger amps ... gets old fast with under power amps. GL!
06-24-14: Edoit
To rephrase my question, which of the 3 on the list would be the best match for shindo masseto pre amp?
My suggestion is that a more important consideration is which of the three amps is the best match for the speakers. As you can see in the impedance plots for the SHL5 shown here, its impedance is in the vicinity of 6 ohms in the mid-bass and upper treble regions but rises to a peak of about 34 ohms at a little under 2 kHz, which of course is a particularly important part of the spectrum. The interaction of that impedance variation with the relatively high and also model-dependent output impedance of a SET will cause significant tonal balance variation as a function of which amplifier is used.

It follows from that, also, that a given SET amplifier will likely sound significantly different when used with your particular speakers than when used with many or most other speakers.

One more reason, in addition to those that have been mentioned, to try to audition in your system prior to purchase, and for why a SET might not be the best choice for use with your speakers.

Regards,
-- Al