New Member, First Project. BF Princeton Reverb.

[Milnoque]

I'm new to this forum.

I thought it would be nice to post just to say Hello.

I do have a couple of questions,
I'm planning to begin my first home built amp. It will be a BF Princeton reverb clone. I have most of the parts and am almost finished mutilating the chassis.

I decided to go with new Tung-Sol 12AX7s and 6v6s but I'm still confused about rectifiers. The schematic calls for a GZ34. I'm very tempted to go with a 5y3. I don't care about volume, Just tone. I thought I'd like the extra sag. If that's not a bad idea who makes a good one. I wanted to use new tubes for repeatability. I was also plannong to use a 12AX7 in the first preamp stage instead of the 7025 in the schematic, Is this a bad idea?

Do you have any advise on selecting a reverb tank?

[stokes]

The 7025 and 12AX7 are interchangeable.I woulddnt be comfortable with the 5Y3 as a replacement for the GZ34.A 5V4 would be more reliable,IMO,and still give you more sag than the GZ34.

[Milnoque]

Thanks

[oahu]

hello.

i recently build a Princeton-Reverb clone and use a 5U4GB, like in the original circuit (AA1164). they are availiable new from EH, TAD, and so on. it depends how much you like to spend on it. i now use a NOS RCA.

for the preamp tubes, a 7025 is only a high-grade version of a 12AX7. i would just put the best 12AX7 in the V1 position (try different ones!). but i guess, the tung-sol tubes are a pretty good choice. i use a 5751 in the V1 position, which is a lower gain (ca. 70% compared to 100% of a 12AX7), low noise version.

have fun with your princeton-build, greetings from vienna...

[Milnoque]

It's so cool that I can get advice on a Fender amp from a guy in Vienna Austria. Hello from North Carolina and thank you.

I decided to stick to the schematic for the initial build. and get that working before I try to get creative. It calls for a GZ34 for the rectifier. I'll probably go with a JJ Tesla. I don't know why.

Off topic: I noticed your handle. Do you have any information about an Oahu MOTS model they made with 2 X 6F6, and 1 X 6n7? The rectifier is an unmarked 4 pin coke bottle. I'm guessing the amp is early '40s. I believe the matching lap steel is a Dickerson. None of the schematic sites I know about is any help.

[sportster4eva]

Not familiar with that amp, but I would venture a guess and say the rectifier is an 80. Similar to a 5y3, but in a 4 pin ST envelope.

[oahu]

oahu amp

hello.

sorry, i only have this lap steel, it is a 1957 tonemaster, which was made by valco. oh, and it sounds great don't know much about their amps, but you maybe will find the schematics when looking for valco amp schematics, as valco made the oahu-brand amps.

it also could be possible that it is a magnatone amp, as you mentioned a dickerson lap-steel, which was a magnatone brand. you can find some of them here:

http://www.vibroworld.com/magnatone/index.html

i like to have a leilani model somewhen, just for the looks. but they are really hard to get here in europe.

greetings from vienna

[dobsont]

BFPR info

Is there a good place to find practical info on homebrewing one of these? I've got the schemo and layout from schematicheaven.com

What other resources are out there? Let's post links!

[oahu]

hello.

what helped me a lot building my princeton is this:

http://www.tubeampdoctor.com/newsdes...newsdesk_id=53

greetings from vienna

[Milnoque]

For my project I'm using "Building Vacuum Tube Guitar and Bass Amplifiers Volumes 1 & 2" by Tino Zottolla. The approach he uses is more like a cookbook, step by step. I have found it very helpful. I got mine from e-bay. Volume one is a beginner's guide with a few amp projects. The princeton reverb is in volume 2. There is a third in the series.

The other book Ive found helpful is Dave Funk's "Tube Amp Workbook". It contains the best explanations of circuits I've found. I don't profess to understand all that I've read in there, but it's obvious that as I work through my build, I'll get a lot of the way there.

Hope that helps. If someone more experienced has an opinion on my choices, I'd like to know.

[dobsont]

I'm collecting links too.

This is an interesting thread:
http://music-electronics-forum.com/s...ad.php?p=48461

[oahu]

books & links

hello.

i can also recommend the following books:

"The Tube Amp Book" by Aspen Pittman (with cd-r containing lots
of schematics)

"How to service your own tube amp" by Tom Mitchell

"Great Tube Amp And Guitar Mods" by Mike Thompson

you can also find some usefull infos here:

http://www.pacificrecone.com/JackDarrBook.html
http://www.tone-lizard.com/index.html
http://www.geofex.com/
http://www.el34world.com/schematics.htm
https://taweber.powweb.com/store/kits.htm
http://www.mojomusicalsupply.com/
http://www.missionamps.com/

hope this helps a little, greetings from vienna.

[dobsont]

I'm just finished/still tweaking a 5e3. Now I really want a BFPR...
I'll keep posting useful info here. This is turning into one of those very handy threads...

(Oahu: Hello from Winnipeg and thanks for that Jack Darr link. I passed your city on a train last summer. Couldn't stop though I really wanted to. )