Bugle 45

[Opa1]

I've been reading over Gordon Rankins 45 design for a few days. I'm thinking this is the direction of my next build. I have the parts for a quick and dirty prototype just to see how it sounds.
I think Nate used this design for his 46 amp. That would also make a nice amp. With a few changes a 2A3 could also work.
Have any of you owned, built or heard the Bugle?

http://wavelengthaudio.com/bugle.pdf

 

[Golden Gate ER]

I've not heard a bugle amplifier however I've worked with alot of antique equipment that use a single and/or multiple 45 tubes. This 45 tube circuit is so primitive there is little to no difference between them. I have found them to sound better when a 81 pool rectifier is used in the power supply.

 

[mhardy6647]

Gary Kaufman built one a long, long time ago (actually a 45/46/300B "convertible")-- his sounded great.
https://web.archive.org/web/20040804...rg/Ragtop.html

... as did his version of the Angela/JE "Simple 45" :-)
(with very vintage 45s)

EDIT -- image added in a later post

http://www.enjoythemusic.com/bostonbash99/

 

[billfort]

I've been intrigued by the Rankin design since first reading about it in Sound Practices (link to article) as it just 'fits' my little mantra of less-is-more and uses my all-time favorite output tube, the 45. The reason I want one so much though, is also the reason I've never built it - the 45 tube - which so far, just doesn't cut it in terms of output power on Altec 604s.

2A3s have become my 'bottom line' power wise and that's a great place to be but I still listen to 45s when my mood warrants - I love them! I've been told that with a different driver tube than what I use (maybe a C3G instead of the 417A) I might find that 'drive' I'm looking for that puts the 45 over the 2A3 so I'm not done and sure will watch where you go with this Mark!

You are on the pointy-end of getting the sweetest cream out of those Altecs - this should be fun.

 

[billfort]

Welcome then - it's a great place down here.

 

[mhardy6647]

 

[marantzfan]

I'll be converting my Paramounts to 2A3's soon too. Don't need all the oomph of the 300b right now and besides, I'm supposed to be building a pair of 300b mono blocks.

One day, I would like to try 45's. My listening space is considerably smaller (but not small) than in the previous house so maybe I can pull it off. Maybe.

I'm excited to see what you do here Mark. You've been a busy builder recently.

 

[Opa1]

This is the start of the Bugle 2A3/45 amp. It's all most leftover parts. This will have the industrial look for sure. No build thread this time.

 

[Sarchi]

No build thread this time.

Say what man?? You aren't getting off that easy, Mark. We want a build thread!

 

[Opa1]

As you can see, these will be mono blocks. I still need to decide what caps I want for the PS. Then I'll see how it lays out. Iron on top or bottom?

 

[Redboy]

No build thread, whaaaa?!?

And dang, those parts came together fast!

 

[Opa1]

I had to do some thinking on this build. That little red guy with the pitchfork keeps poking me. I need to use the iron or my grandkids will wonder what it was for. I'm going to stay with what I started with and use electrolytics in the PS. This might look like a Maggie console pull but it should work ok.

 

[Redboy]

I like these caps - Panasonic EDs - for 'lytics. They're high quality, reasonably priced, and quite small.

 

[Opa1]

Started some layout ideas. Mirror image. The plate will be 6.5x9 when I shear in half. Hope I fit it all in there.

 

[StevenZ]

Sweet! Though it may be "ugly" I bet it'll sound really nice. What preamp are you going to use on these, Mark?

 

[Opa1]

Did some work. I have to layout some things to make sure its going to fit. I ran into a few snags with the PS. So this amp will be part Bugle/JELabs. It will have a 12AT7 input with 2A3 out. I'll leave room for better opt's. Not sure what to call it.

 

[Opa1]

Have the top plates done. They were very rough so its not perfect. They have a few deep scars. Took most of the day just to get all the holes in the right place. It's a challenge to put all this stuff in a small area.

 

[StevenZ]

Looks good. Won't be long now!

 

[billfort]

Looking good Mark! I think you are going to like these.

 

[Opa1]

Thanks guys! This is the stopping point for today. They don't look that bad. Might have to bust out and buy some James OPT's.