watt finally builds an amp (results TBD)

Thanks for looking, gable.

I wouldn't say I'm 100% confident in any joint soldered to those strips (I found that these didn't take the solder very well, and the holes are really big to fill), but I just shone a light on those, and I think you're seeing reflection. They're full, and the wire's in there pretty good. Still, that is the 6.3V winding, so it couldn't hurt to touch it up. I'll do that.
I've had trouble with those strips occasionally. Sometimes the are fine other-times I struggle to get a decent looking solder joint. I have since moved on to those ones in my pictures above. AES has them.
 
Also, I can't seem to find where your recitifier's filament is tied to one leg of the anode. I could just be missing it in there.

I'm not sure that I understand, though I'd like to.

I registered some confusion about the rectifier connections in post 43. Redboy answered in 46, and I thought I understood what to do after that.

Pins 6 and 4 (anodes, yes?) connected to HT winding, 8 and 2 connected to the 5V winding, with one leg of the filament also connected to the choke and C1.
 
I'm not sure that I understand, though I'd like to.

I registered some confusion about the rectifier connections in post 43. Redboy answered in 46, and I thought I understood what to do after that.

Pins 6 and 4 (anodes, yes?) connected to HT winding, 8 and 2 connected to the 5V winding, with one leg of the filament also connected to the choke and C1.

Oh, I mis-spoke, my apologies!

After a better second look, you have that wired correctly, per the schematic.
 
I think I still have a little work to do tuning the power supply, but I've been using this amplifier on and off for the past week. With the Slagle AVC in front, playing through a pair of 605Bs, it's really enjoyable. Great tone. Surprisingly good extension.

P1020306.JPG

Have I forgotten about the Line Magnetic 300b that's sitting on the floor across the room? No. But this project has given me a sense of the satisfactions that can come from building a tube amp. I get it now, and I think I'll do it again (he says, knowing that there's a pair of Acrosound outputs on a shelf in the closet). But first I'm going to listen to this one for awhile longer. It does sound good.

I appreciate the help and encouragement that you all offered along the way. Big thanks to Redboy, who answered my PM'ed questions without telling me to put a sock in it.
 
Seeing all of that space on top of the rack, I guess I need to build a bigger amp next time. :)
 
I know. I bought them a year or so ago, really without to clue as to how I'd use them, to force myself to finally try to build something.

Coming soon to a thread near you . . .
I know that game.

I bug @gable far too often with questions about what's what. Thankfully, there's a kind of person called a friend and they put up with that stuff.

Congrats on the build!
 
This bring back memories with my Granddad, when he showed me how to build valve kit.
One was the PSU supply, the inductor/choke at 50 and 60Hz is massive, we/he used multiple voltage doubler circuits after the main HT transformer, so as you double the voltage you also double the frequency of the ripple thus reducing the choke and bulk capacitors needed. I wondered has anybody tried that here?
So with a secondary winding of 150VAC it was easy to get to the working voltage he needed.
If I can I will dig out is log book and put up his circuits and calcs.

Radio Ham books are a great source of good solid information. There was some in PDF form on www.archive.org check it out. (oh and some nice music)

Yours

G8XIV
 
@watt - Back from the dead. I was going through some old threads and came across this one. So, what ever happened to this build?
 
@watt - Back from the dead. I was going through some old threads and came across this one. So, what ever happened to this build?

Not exactly an easy thread to find, since I mis-posted it in the Intros forum.

I still have the amp. I haven't put it into the system in a few months, though. I thought, a week or so ago, about ordering some fancier coupling caps and maybe building a new base for it, one with finger joints or something a little more spiffy than the way it stands. The fact that it's on a shelf isn't a knock on the amp--my life is just busy busy at the moment, and I've been happy enough with the integrated, an Almarro 318B, that I'm using not to make any changes.

I got a kick out of re-reading the posts in this thread. Sincere thanks, again, to everyone who pitched in to help and educate me. Three years ago? I've forgotten so much! After building this particular amplifier, I got psuedo-serious about building more, buying a decent tube tester, calibrating it, and also buying the transformers, assorted parts, and so on for a few different circuits. Who knows, maybe this summer is the summer when I'll make some progress. I have access to a couple of laser cutters at school that could be useful for fabricating top plates . . . That could be fun.

In any case, thanks for asking. I'm glad that I dove in and tried it. I guess I should do so again!
 
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The Almarro is nice. I had the pleasure of spending a lot of time listening with the company president years ago.

I could build you a nice base with corner splines, if you are interested.
 
I had an A205 for a little while when I lived in far north Austin, the prime I wanna hear everything gear merry-go-round days. I liked it a lot. That amp is what led me to the 318B, which I've had for I guess around ten or so years now? It has gotten more expensive to re-tube with the cost of 6C33C these days. I would looooooooooove to have listened some with the company president, especially if those speakers were involved.

I could build you a nice base with corner splines, if you are interested.

That's so nice of you. I'll PM at some point today. Maybe we can set up a time to talk. It's been too long.
 
Yes, the Almarro speakers are incredible. It was amazing how big the sound was from small drivers and flea watts. A friend of mine, bought all the demo gear and speaker at a good price, because they didn't want to ship it back. I've been trying to buy the speakers for years but he won't sell. Sad because he doesn't use them. He just collects audio.

M1A paired with the 205, and the larger M3A mated with the 318B. Yoshihiro Muramatsu designer

1almarro01.jpg
 
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Actually, Luther, I got the M1As from the show. They've been happy here, ever since.

If I ever get the space, a 318A and M3As will be on my 'must have' list.
 
Nice memories there guys. :)

Now was that the luxury ex-ho-jo resort or from a fest after we moved into more mundane spaces?
 
I'm thinking it was the ex-HoJo as I bought my 205 from BrianB there; that could be it on the table!
 
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