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After a long night reading I seem to considering one of two types of circuit; the baby ongaku or loftin white. 

Is one much better/simpler than the other? 

On the subject output transformers, any suggestions of suitable sources. I have looked at electro-print, but wondered if there is anything manufactured in the UK. 

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I have sowters,  ae & tribute, my tributes are the best in my view, but unfortunately no longer available, luckily I have 3 pairs of those. 

I also have a few other lesser transformers somewhere.. 

Sowters are good only drawback is a slight colouration compared to amorphous. 

When I first started out I used  cheaper s/h parts, I think its sensible if your building your 1st amp. 

This weekend I've built a set amp on a board, it's a 2 stage mazda ac/hl choke loaded driving a mazda pp3521 into sowter 2k txs  It makes about 2 watts. Seeing we missed out on kegworth, I had my own hifi weekend, I've had the output valves a few years and have been waiting for the motivation to build. 

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4 minutes ago, steve 57 said:

I have sowters,  ae & tribute, my tributes are the best in my view, but unfortunately no longer available, luckily I have 3 pairs of those. 

I also have a few other lesser transformers somewhere.. 

Sowters are good only drawback is a slight colouration compared to amorphous. 

When I first started out I used  cheaper s/h parts, I think its sensible if your building your 1st amp. 

This weekend I've built a set amp on a board, it's a 2 stage mazda ac/hl choke loaded driving a mazda pp3521 into sowter 2k txs  It makes about 2 watts. Seeing we missed out on kegworth, I had my own hifi weekend, I've had the output valves a few years and have been waiting for the motivation to build. 

Also, for output transformers, Hashimoto and of course Lundahl. The Tango used to be excellent and are apparently being made again under a different name (ISO), but I've not heard any reports about them.

Here you go. Transformer heaven: http://www.acoustic-dimension.com/

Associated question Steve, and not totally off topic as Fred might need this, depending on the build. What do you use for plate chokes?

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2 hours ago, rabski said:

Also, for output transformers, Hashimoto and of course Lundahl. The Tango used to be excellent and are apparently being made again under a different name (ISO), but I've not heard any reports about them.

Here you go. Transformer heaven: http://www.acoustic-dimension.com/

Associated question Steve, and not totally off topic as Fred might need this, depending on the build. What do you use for plate chokes?

Good question, as that is my next area to explore. 

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This weekend's amp i used little hammond 153c they seem fine.  The px4 amp I built a few weeks ago has some large vintage ones by partridge.

The px25 amp many of you have heard has tribute amorphous interstages.

I've read the little Hammonds work even better doubled up but I have not tried that yet

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And.... by coincidence I ended up discussing this today with Andy Evans. He suggests a pair of Hammond 156Cs in series for 26 or similar. You'd need to do the calculations for a power valve in terms of current. The 'trick' part of what Andy suggests is to wire them in series with one wired each way round so to speak to reduce hum pickup, etc. Bloody clever that.

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12 minutes ago, rabski said:

And.... by coincidence I ended up discussing this today with Andy Evans. He suggests a pair of Hammond 156Cs in series for 26 or similar. You'd need to do the calculations for a power valve in terms of current. The 'trick' part of what Andy suggests is to wire them in series with one wired each way round so to speak to reduce hum pickup, etc. Bloody clever that.

That's just what read.. Next time I'll give two a try. 

If I remember correctly a single is rated at 7 ma,  I tend to put high current drivers through an interstage,  just my preference. 

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Yup 8mA I believe. OK for a driver stage, but that's probably overkill here.

I'll start a separate thread in DIY in a day or so. Some of Andy's spare stuff plus some of what I have here are likely to come together in the shape of a 26 pre....

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On the speaker front, I have just ordered a new set of Fostex fe208sigmas along with a set of t90 tweeters to replace the dead units. 

Apparently they had been used as a 'disco' speakers in a church, but had stopped working for some reason! 

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It's a combo I used to use Fred.  The 208's in a Fostex design back loaded cab 

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This isn't replacing my main set up, more of a project while I am say we say less busy. 

The cabs are Dallas 2's with solid Walnut front baffles and another solid wood for the rest, just not sure what yet, but it's hard, very hard. 

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Have you decided on the main circuit yet Fred?

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