Advice pls! - Have I damaged my amp with my speakers?

[JANDL100]

My new (used) Chinese OTL valve monoblock amps are mis-behaving ....

- significant hum thru the speakers and a "ticking" from one amp (again thru the speakers).

Curiously, the ticking can be shown to be caused by only one of the monoblocks, but it comes thru both speakers (and also thru small rear/surround speakers which aren't even connected to the OTL amps!). But turn off the 'problem' amp and all the ticking disappears.

I'm using the amps with my Thiel CS2.3 speakers - quite a low impedance in places. But the amps are rated at 40W and even when driving quite hard the transformer cases get quite warm but not hot.

Just doing some on-line research (why didn't I do this before buying the amps? ) I see that high impedance loads are the thing to use OTL amps with ..... .... so probably Thiels aren't ideal then

BUT - would component damage result or should the amps just sound wimpy and/or distorted? (they don't).

I bought the amps on eBay - if I've caused the damage, I can't really complain to the seller!

Advice from them who knows about such things please !!

 

[lordsummit]

Sounds like it may be a dodgy valve, try a re-bias then some new ones. Most funny noises I had with valve amps were due to valves on their way out

 

[speedy.steve]

My lilmited understanding of such things is that a vavle/tube amp will more happily drive a dead short than an open circuit.
I had a dead short once in a speaker cable and all I got was no sound out of that speaker and no damage to the amp / valves.
I've never tried driving an open circuit with the amp...

Solid state amps like it the other way around and usually have short protection circuits.

You low impedance speaker are tending towards a dead short rather and open circuit... I doubt even 2ohms would kill a valve amp. 4 ohms is bread and butter, 6 - 8 the norm. Someone will correct me if I'm talking B'lox.

I'd look to the tubes. Are they heating properly. Does the clicking sound come up after the heaters are working.

Can you try another set of tubes?
Is your source working ok?

 

[rollo]

Bummer. Dude. Try swithing the tubes from one amp to another. Process of elimination. sounds like a tube to me. Good luck trying.


rollo