Valve Amps

[Dad3353]

A valve preamp doesn't do the same job as a valve power stage. Pushing an output stage, with its transformers, is not emulated by a valve preamp. Not that a valve preamp is bad at all; it's just not, in itself, a substitute for all-valve.
Just my tuppence-worth.

[Roland Rock]

[quote name='Dad3353' timestamp='1457676052' post='3000826']
A valve preamp doesn't do the same job as a valve power stage. Pushing an output stage, with its transformers, is not emulated by a valve preamp. Not that a valve preamp is bad at all; it's just not, in itself, a substitute for all-valve.
Just my tuppence-worth.
[/quote]

I agree with our esteemed father - a valce pre hybrid amp has much more in common with a solid state amp than a full valve jobby.

Where are you Bob the Dog? I have a 100w no name valve amp you could borrow to see if you like them

[Bobthedog]

I thought the LB30 / CTM30 were all valve?

Roland, I am nr Buckingham so a little bit of a drive, but certainly not impossible one weekend. Very kind and thank you. That may be a better option.

Edited March 11, 2016 by Bobthedog

[Bigwan]

[quote name='Bobthedog' timestamp='1457693321' post='3000975']
I thought the LB30 / CTM30 were all valve?
[/quote]

They are.

[Pow_22]

They are, the CTM15 is hybrid (and naughtily advertised as All Valve by ashdown)

[LewisK1975]

[quote name='Pow_22' timestamp='1457695601' post='3001001']
They are, the CTM15 is hybrid (and naughtily advertised as All Valve by ashdown)
[/quote]

These are the specs in the manual:

[attachment=214410:Capture.JPG]

How is it hybrid if it has valve input and valve output? I'm really not criticizing your comment, just curious that maybe there are more ways to describe 'hybrid' than I know about...

[Lw.]

Actually look inside - it's not an all valve signal path on in the CTM-15's (not seen inside the others).

[LewisK1975]

Goodness, there was me thinking if you had a valve input and valve output power, you had a valve amp!

[taunton-hobbit]

The older ones on here tend to think that a 'valve' amp is just that, with no fancy electikery & chips stuffed somewhere in the signal chain...good/bad ? That's a user decision - but it should be an informed decision, imo.

[Bigwan]

[quote name='LewisK1975' timestamp='1457697643' post='3001034']
Goodness, there was me thinking if you had a valve input and valve output power, you had a valve amp!
[/quote]

Looking at the PCB layout (there are pics online) I VERY much doubt it has a valve input. There are 3 valves on the CTM15. 2 for the power amp (2 EL84, typical for 15 watt amps) and one 12AX7, but it's placement would suggest it's doing phase inverter duty. There's lots of "sand" between the input and the valves...

LB30:
[attachment=214412:lb30guts.jpg]

CTM15:
[attachment=214411:ctm15guts.jpg]

Edited March 11, 2016 by Bigwan

[LewisK1975]

[quote name='Bigwan' timestamp='1457699564' post='3001058']
Looking at the PCB layout (there are pics online) I VERY much doubt it has a valve input. There are 3 valves on the CTM15. 2 for the power amp (2 EL84, typical for 15 watt amps) and one 12AX7, but it's placement would suggest it's doing phase inverter duty. There's lots of "sand" between the input and the valves...

LB30:
[attachment=214412:lb30guts.jpg]

CTM15:
[attachment=214411:ctm15guts.jpg]
[/quote]

Thanks Bigwan - Glad that I have class-d. At least we all know what's inside them, or do we?

[Beer of the Bass]

Since the ECC83 is a dual triode, if they used a cathodyne phase inverter (which uses one triode) in the CTM15 the other triode could be part of the preamp. Though to have tone controls and enough gain to overdrive the preamp would require more stages than that. If the master volume is after that one triode in the preamp, they may have arranged the gain staging so that any preamp overdrive is coming from the valve, but it would still be more honest to describe it as a hybrid preamp.

[Merton]

edit - late to the party!

Edited March 11, 2016 by Merton

[Bigwan]

[quote name='Beer of the Bass' timestamp='1457701139' post='3001087']
Since the ECC83 is a dual triode, if they used a cathodyne phase inverter (which uses one triode) in the CTM15 the other triode could be part of the preamp. Though to have tone controls and enough gain to overdrive the preamp would require more stages than that. If the master volume is after that one triode in the preamp, they may have arranged the gain staging so that any preamp overdrive is coming from the valve, but it would still be more honest to describe it as a hybrid preamp.
[/quote]

All possible but, as you say, it's CERTAINLY NOT an all valve amp.

[Pow_22]

Where do Ashdown stand on the whole 'false advertising' thing then? Don't get me wrong, im not an ashdown basher (I loved my Spyder 330 and my drophead 200) but how can they continue to list is as all valve?

[taunton-hobbit]

I don't think Ashdown have problem - nowhere do they say 'does not contain additives'
they list their valves and leave it at that (apart from the marketing guff).
It (allegedly) has valves on the input (eventually?) and on the loud bit.....
thus it is a 'valve' amplifier.
Whether it's as much a valve amp as my Ormat is debatable.....(imo....exclusions apply)

[afterimage]

Look for a good serviced sh one a good saving over new a got a Traynor yba200 for five hundred b stock from Thomann 200Watt's nice

[basskit_case]

Ashdown's Facebook page had an update recently saying that the lb30 may be brought back into limited production