Superfly in a 1590A - You can build one too

[Perrow]

When I posted pictures of my 1590A Superfly build a few months ago I promised to post more information soon. How soon it is can be debated, but here it comes.

I've created a page on my stompbox wiki, detailing (hopefully) everything needed to build it.

http://rumbust.net/tiki-index.php?page=Superfly+in+a+1590A

I'll throw in a few images here to tease you

[frequencycentral]

Great attention to detail and a really good wiki! Well done!

[Perrow]

Great attention to detail and a really good wiki! Well done!

Thanks, I lived with this project for a little over 6 months, working with it almost daily, so it's almost an intimate thing writing about every detail. I do hope it gives someone else the courage to try this build.

As for the effort involved I can say that the CG image of the gutshot, done in Google Sketchup, had me sitting for hours on end moving things around, testing and improving things.

I can't count the times I've said "well this must be the final version of the pcb layout" only to see another (possible and often actual) improvement minutes later. On any other build I'd say; "well this looks nice I'll stop here", but with this one that simply weren't an option. Just as a little fun, I thought I'd show you an early version of the layout, this one is from before I thought about putting it in a 1590A.



At this stage I had the pinout of the mosfet wrong, and I think a load of other errors. I planned a hole in the amp board to be able to adjust the trimmer, needless to say that vanished somewhere in the process. It's safe to say that not much of this design survived intact but almost all components in this version of the file is the same (as far as digital copies of something can be the same) as that on the final, or is that current, version. They've just been moved around or had some property changed ad infinitum.

While working on this I've sometimes saved to a new file, just so I could go back to the old version if I didn't like where some change would take me. Most versions got at least a few days (~5 to 10 hours) worth of changes before I saved to the next version. The image above is version 1 of the file, the one posted on the wiki-page is version 19.

I've learned so much through this, but I don't think I'll ever do this kind of journey with another circuit, either it'll fit a 1590A (somewhat) easily or I'll use a bigger enclosure.

[phector2004]

Nice!

An incredible build... I'm not shocked it took 6 months of planning to get it right
and it's so neatly laid out... with step-by-step instructions... if only I could etch!

I know what it's like working with google sketchup. By the time you decide exactly how you're gonna do it, a new layout pops into your head and it's back to the drawing board. Usually happens 4-6 times before you settle on the final layout!

Cheers and congrats


btw is that my Switchcraft-style Jack Google model? I've been hoping someone would put it to good use 

[markeebee]

Per, that sketchup drawing is beautiful. The whole project is beautiful. You should be very proud.

[Perrow]

Thanks

Yes phector, I found the Switchcraft jack in the repository, it helped take away a lot of uncertainty about this build. I do thank you for it.

Rob, deadastronaut, asked me about the ground fill. It's done just using a lot of traces and possibly some boards colored black (on the phone right now and don't quite remember if I used any on these boards).

[iccaros]

Perrow
that is outstanding work.. A little jealous I am ..  I am having issues with the normal size.. too tight.. have blown two transistors measuring voltage and slipping.. 
Keep up the good work.. your an inspiration.. now back to ordering more parts...

[Perrow]

too tight.. have blown two transistors measuring voltage and slipping.. 
Keep up the good work.. your an inspiration.. now back to ordering more parts...

I soldered on short(ish) leads when I got tired slipping. Then clamp on the multimeter and have your hand free to adjust the trimmer and get zapped by the HV (just once for me, thanks, not keen on doing it again).

I will try to keep up the good work, I fear though that I've peaked

[nexekho]

I will try to keep up the good work, I fear though that I've peaked

Hmm... what's the most complex thing one could fit in the smallest box...
Anyone know where I can get those pots like the volume controls on a Gameboy?  Use 3.5mm jacks and it should be possible to make some insanely small stuff...

[Perrow]

I will try to keep up the good work, I fear though that I've peaked

Hmm... what's the most complex thing one could fit in the smallest box...
Anyone know where I can get those pots like the volume controls on a Gameboy?  Use 3.5mm jacks and it should be possible to make some insanely small stuff...

Surface mount components and an spdt switch. I mean with smd and four layer boards, you could stack a bunch of boards! There'd be no limit to what circuits you could fit in a 1590A

[frequencycentral]

I've built a dozen or so Superfly into 1590B, and a couple of dozen Murder One into the same size enclosure. I've got my build time down to about 6 hours, that's including everything including sanding, etching and painting the enclosure - I can't imagine how long it would take to shoehorn one into a 1590A. Personally I wouldn't attempt a 1590A submini tube amp build - nice to have a bit of space around those high voltage parts that can hurt you.

I've considered doing a 1590A build of a Superfly type amp based around these DM160 micro tubes, but the limiting factor is the size of the transformer. Now, if I could find a suitable transformer significantly smaller than a 125A.........

[Perrow]

I briefly considered using some other connection for the speaker, feels like that could save considerable space. More than once I considered having the jacks on leads outside the enclosure.

For anyone considering this build I can say that using the leads supplied with output transformer all the way to the board will make for a tight squeeze. I squeezed for a while and made them fit, but it would be far easier to use thinner hook up wire. They should be able to handle all the power this amp can supply.

[nexekho]

Surface mount components and an spdt switch. I mean with smd and four layer boards, you could stack a bunch of boards! There'd be no limit to what circuits you could fit in a 1590A

I'm in love with the idea of a mini board covered in mini matchbox/Tic Tac box sized pedals

[Scruffie]

I've considered doing a 1590A build of a Superfly type amp based around these DM160 micro tubes, but the limiting factor is the size of the transformer. Now, if I could find a suitable transformer significantly smaller than a 125A.........

I wondered what was going on with those DM160s... tempted to grab a few.

[frequencycentral]

I've considered doing a 1590A build of a Superfly type amp based around these DM160 micro tubes, but the limiting factor is the size of the transformer. Now, if I could find a suitable transformer significantly smaller than a 125A.........

I wondered what was going on with those DM160s... tempted to grab a few.

I've four, but apart from taking them out of their boxes to lick and kiss them occasionally............. 

[iccaros]

I wonder what the OT needs are for those DM160.  They are eye tubes so audio is not their what they were intended for. but to feed 750uA... at 30v is 40K, if I did my math right..

I am not sure it matters at this size, if 1K:8om would work then Radio shack has theses http://www.radioshack.com/product/index.jsp?productId=2103254
I have a few of them, I can send someone who wants to try..

[Perrow]

I'm in love with the idea of a mini board covered in mini matchbox/Tic Tac box sized pedals

The 1590A multi effect 

[exabrial]

Do you have a final circuit diagram with your tone stack, standby, and trim pot enhancements? I don't think I'm brave enough to build this into a 1590a, but I like your mods!