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Re: I do use OTL's and personally love them...

I think this has much to do with the OTLs colorful history (which I will admit I do not knpow much about) and background with Julius Futterman and then the late Harvey Gizmo Rosenburg. The early OTLs had a reputation (deserved or not - I cannot really say I as I was not around in this hobby at that time) for poor reliability (blowing up (not literally), destroying speakers etc etc) and you got to say that Harvey was a rather colorful character and that porbably either turned folks on or push thier buttons in a bad way.

Now, the traditonal/coventional OTL design is one that requires many tubes to get a output impedance suitable for driving conventional speaker loads. The large number of tubes means lots of heat which is not accetpable for some users or domestic situations. Since you have a large number of tubes, the odds of a tube failure increase (especially if the design was working the tubes hard or the quailty of the output tubes in use was not great under such long and hard use)... in earlier OTLs a failure could well result in damage to amp and or speaker.

So, the amps wind up getting the rep of old British sports cars... a PITA to maintain, not very reliable, etc, but really fun to drive! :-)
i.e. OTL myths were formed and have stuck to some degree over the years.

Fortunately, they are myths... modern day OTLs use great tubes which work really well for the OTL application and are very reliable. Designers like Ralph Carston, Jud Barber, Bruce Rosneblit etc have built amps which are very reliable and stable and deliver many years of trouble free performance. As well, when failures do occur (as they will), no fireworks and no speaker damage occurs... a fuse gets replaced and or a tube gets replaced and the customer is back to enjoying the music.


Happy Listening,
Rich Brkich
Retailer & Audio Asylum Industry Liaison


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