Is this impossible?

[Clive]

Hi David,

I've not heard the WAD amp but I remember Nick Lucas telling me that it was more about power than refinement.

I suppose bi-amping could help you a little but wouldn't give you much extra headroom.

Hopefully someone has experience of a higher power PP, maybe even KT90.

[steve s]

dave there is alot of **** talked on what does what, and whats the best type of amps...

the el34 amp would not be in triode mode...

but in triode mode it would not be as loud but it would also not run out of steam so easily...

the sound you looking for have you heard it on your speakers
just cos they cost 2.5k don't make them good.. and most of us have different ideas what good is anyhow...

how loud do you listen.. (do you have a sound meter) it not allways about watts.. speaker impedance and the amps ability to handle it.. and how much the crossover saps the music away.. bought speakers and amps don't always use the best components.. drivers & crossovers...


really good sound in my opinon comes from a balanced system, some amps suit some speakers and the only real way is to try it out... valve amps do tend not to be understood...and pigeon holed...
I don't know where your based, but most most folks around hear would welcome you and your speakers to test on their amps.... that could save you alot of time and money..

what your after is the musical highs and the abilty of the system not to get lost with complicated music..

thats not about watts

its about very good valves in amps with good components, using power supplies that can (supply!), and speakers that will not dilute too much what signal the amp makes and that are capable of reproducing the finer details
and all that without too much distortion at high sound levels, that goes for the amp too...

happy hunting
steve

[david.rogers]

Thanks for your input Steve. I would be very happy to welcome bottleheads to Rogers Towers (here in Henley-on-Thames). I can't travel with the speakers as they weigh a ton (granite sides) and are pretty well immovable without a fork-lift truck! I would certainly welcome anyone who wants to bring along their favourite valve amp to try them out. The speakers have a very large ribbon for mid and highs, and a cone speaker for the bass. My tastes are at the opposite extreme from Naim (for example), I look for transparency and 'hear-through'. I think there MAY be a slight mismatch between my speakers and my C-J MV55 EL34 PP amp - although I know the speaker designer (Danish) developed them with valve amps. They actually worked quite well with the K5881 I built a while back, although that had a darker ambience than my C-J. I have just read that WD is to produce a KT88 based kit and that may - just may - be what I am looking for!

[James D]

Hello Dave,

Can you tell us what your speakers are and what the impedance curve of the speakers is?

I suspect it is not power per se that we need here but more the ability to drive the load of your speakers. Going down the pure power route is a fools game anyway - to produce a subjective doubling of loadness requires about a ten times increase in amplifier power, a doubling of amplifier power is only just detectable as an increase in loudness... so thats not what we need.

Driving current into your speaker is likely to be the real issue and so knowing the impedance curve is a good start to matching the current drive requirement (and voltage drive of course) Any detail on the drivers and crossover used will help as well. I suspect you may have an impedance curve that dips very low and is nominally 4 ohms in the first place. Pentode valve amps rated for 8 ohms would run out of steam into such a load quite quickly. You would need a good triode amp designed for 4 ohms or a vary powerful pentode amp set for 2 or 4 ohms (pentode amps in Class AB quite like higher loads but don't like lower loads than they are expecting)

I guess the other practical aspect is budget and would you want to modify what you have or start from scratch?

ciao

James