View Single Post
  #7   Report Post  
Posted to sci.electronics.design,rec.audio.tubes
Phil Hobbs[_2_] Phil Hobbs[_2_] is offline
external usenet poster
 
Posts: 17
Default Tube mono-block amp with SIX 6L6 outut tubes

On 12/28/18 3:45 AM, wrote:
On Thu, 27 Dec 2018 21:11:35 -0600,
wrote:

I'm not intending on building this, but it's interesting and makes me
wonder if someone could use EIGHT 6L6 tubes, or TEN?
(Of course adding more tubes mean bigger audio output transformers and
heftier power supplies.


Tubes may age at different rates, so the characteristics might be
quite different after a long time. It might not make sense to replace
a single (failed) tube and you may have to replace the whole set of
tubes with new tubes preferably from the same manufacturing batch.
This can be quite expensive :-)



Unless the tubes are arranged truly symmetrically, e.g. in a circle with
vertical air flow, they won't all run at the same envelope temperature,
which means they won't have the same cathode temperature either.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com