• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
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    the safety precautions around high voltages.

SE-OPTs

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Anyone have a decent set of SE -OPTs for 300B sitting around that they are willing to sell-trade? I will be putting a post in the swap meet area, but just though I would ask the question from those of us that love tubes. I have the hammonds in my amp, they're ok, tried Edcor...but looking for somthing better.
 
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Why buy someone else's cast offs unless they happen to be high end Tamura, Tango, Hashimoto or Magnequest that is? LOL

I'll put in a plug for new ones custom built by Electra-Print as I am a satisfied customer.. Not too expensive either..

Here: Electra-Print.com High-Fidelity Audio Tranformers

Hammond OPTs IMHO are near the bottom of barrel, most Edcors are a significant improvement as are Transcendars, if you are looking for better you will need to spend some coin.
 
I have a lot of respect for kevin, I haven't heard transcendar or edcor, but I have used hammond many times, and apart from the cheap mains tx's, I haven't had a problem with them, they have been fine for me.

everyone will tell different things you have to decide for yourself.

I tend to think electraprint are pricy, and one I heard I didn't think much of, a line output tx'.

I am not entirely sure if tx's really are a get what you pay for, there are only things like teflon insulation, silver is only 6% more conductive than copper, and its opoinion if it sounds better or not.

as to that, its tx core material and in s.e., gap, that's all.

how does the ear know which tx core material sounds better, does it follow better measurement sounds better, if thats't the case, lets all buy state of the art class D amps, or SS ones with 0000% distortion, as to single end tubes with 5-10% 2nd harmonic, well.....

personally, the rest of a tx is about low end, inductance, and hi end...capacitance, and the hi is rather difficult to predict, its the winding pattern, very complex, so I think sound cant' really be engineered in, and thus any tx could end up being a dog, even 1000s price, or a cheapo be magical...

I am of this opinion about tx's until I hear definitively. as long as its competantly designed it should be fine.

A huge problem imo is that you are expected to shell out mucho cash in the case of bespoke ones, and they may be fab or dogs, yet you can't compare with others or send them back
you just have to have them.

I know its not fair on bespoke makers, but I htink this is a problem, we should be able to try out and compare with others somehow, at those prices.

remember too there is colossal snobbery with anything bespoke and terrible bias against cheap, I have had chinese ones I have been delighted with, but I haven't tried bespoke ones.

the electra print sounded bad, but could just be the circuit compared to a tx' less line amp. and nothing to do with the tx.

a tx is simply

core, material
wire type, diameter
insulation material
gap

and coil geometry..., along with the engineering spec., and a little magic, too. its quite simple really

common sense but depends

were you are
what you can get
cash

my faves are silks from thailand so far.
 
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I would really like to try parafeed, but choke and opt $$$. How about CCS active load? Always wondered about a design like Gary Pimms 300b rev3? Anyone try something similar? How about using a PP output for a plate load? I like the idea of a small opt, like a MQ, built with cobalt, high perm nickel or amorphous core material.
 
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