Show us your SMD stuff.

[EBK]

338 in freedom units

You caught me way off guard with that one!   
But luckily, I was not drinking coffee/water/beer when I read it.

DB Cooper style.    (<--actually DB Cooper)

Again, luckily not mid-sip.   

[vigilante397]

Oh I see, alien technology recovered from a crash site.

Something like that One of my new favorite hobbies is to poke around online reading all the conspiracy theories related to where I work (NAWS China Lake). There's some doozies

[Rob Strand]

http://Oh I see, alien technology recovered from a crash site

When they disassemble the little green boxes they always find some variant of a Tube Screamer circuit.

https://i.ytimg.com/vi/VeiUCfwstI0/maxresdefault.jpg

[thermionix]

all the conspiracy theories related to where I work (NAWS China Lake)

I used to work at a "Secret Underground Submarine Base" in the middle of the Australian outback, hundreds of miles from the ocean.  I saw a guy on a UFO TV show refer to it as "Area 53" too.  (There probably is an Area 53, a couple grid squares over from Area 51, which itself is only about 15 miles from Area 6).

[slashandburn]

http://Oh I see, alien technology recovered from a crash site

When they disassemble the little green boxes they always find some variant of a Tube Screamer circuit.

https://i.ytimg.com/vi/VeiUCfwstI0/maxresdefault.jpg

Love this idea.  60-odd years of research on the Roswell UFO and the conclusion on the alien circuitry is "it's just 3.14 million stacked Big Muff pedals"

[vigilante397]

Finally got a mostly-functional version boxed up. The headphone amp sounded better on the breadboard, so I'll have to take a closer look at that. I haven't soldered the dummy load in as I wanted to test everything else first before I really commit to it. Plus I needed a dry fit to make sure I could get everything into a 1590BB So it now has a single input for guitar or amp, a 4/8/16 ohm dummy load that can be bypassed for either using an external cab or for plugging a guitar straight in (the DPDT switch), a gain control on the input of the speakersim, and a headphone level control. The three outputs are speaker out, line out, and headphone out. I don't have the dummy loads wired in yet, I just put them in for a dry fit and I'll solder them once I finish thoroughly testing everything.

The rectangle holes for the displays were milled with my CNC, but you can see the left one had some issues and the right one came out much cleaner. This picture was taken before the jacks were mounted.



And this is how it looks right now with the 100W power resistors in place. It's a little tight in the 1590BB, but it fits

[thermionix]

Maybe a few holes in the bottom plate under the power resistors?

[vigilante397]

Maybe. I also want to hook them up and do some tests with them to see how hot they get before making any decisions. I can thermal paste them and bolt them to the enclosure, but if they aren't even getting warm (my main amp is 15W and my biggest is 45) then I won't bother. We'll see

Ventilation holes isn't a bad idea though. Easy to do and wouldn't really ruin anything. When I was still in the initial planning stages I even thought about a small fan to move the hot air out, but if I stick with the 1590BB then that will be pretty impossible

[vigilante397]

Continuing to refuse to let this thread die I was talking to a friend a while ago and we discussed how cool it would be to have a great sounding all-in-one practice/recording/lazy gigging solution that fit in a 1590B. So my gears started turning, and this is part of what I came up with. This is basically the Alembic F2B preamp with a 6N17B tube. I'm still auditioning cab sims but this one has a simple passive cab sim on it just because it was easy to throw on. The PSU is separate for now since this is just for prototyping, once I establish that all the individual sections work I'll throw them together on a single PCB. I will also be adding a headphone amp (386-based) and a DI transformer for balanced out, but one step at a time for now.

Etching job was a little sloppy (had some loose screws on my stepper motors) and the solder job was sloppy as well (ran out of small diameter solder), but it works and it sounds great







P.S. It turns out you can get 250V SMD capacitors in an 0805 package, which saves quite a bit of space over higher voltage through-hole alternatives. Perfect for sub-mini tubes running at 200V or so.

[temol]

but it works and it sounds great

We need a proof...

T.

[vigilante397]

We need a proof...

I finished it at 2AM so I didn't get around to recording it I'll throw something together when I get home from work this evening.

[amptramp]

It seems like SMD would go well with a Korg NuTube.  I know the Korg NuTube is a through-hole device, but you could mount in in a surface-mount socket.

But your version looks great!

[vigilante397]

It seems like SMD would go well with a Korg NuTube.

It's true, and one of my friends I showed this to mentioned the same thing, but the NuTube is a larger package than a Russian submini, less flexible for mounting, and waaaaayyyyy more expensive (~$3 for subminis vs. ~$50 for NuTube).

[vigilante397]

Shot a quick video of my preamp in action. Nothing quite like my sloppy guitar playing to distract you from my sloppy building

[bluebunny]

• Cool
• Like
• Want

This needs a project thread of its own, please.   

[bean]

Can you spot the error?

[temol]

Can you spot the error?

Empty solder pad and blue cap (or something blue) soldered directly to R38?

T.

[temol]

Shot a quick video of my preamp in action.

Nice! Any changes to the schematic with 6N17B tubes?

T.

[vigilante397]

Nice! Any changes to the schematic with 6N17B tubes?

T.

Nope. I played with values a bit on the breadboard but decided it sounded great with the same values as the original.

• Cool
• Like
• Want

This needs a project thread of its own, please.   

Thanks I suppose I could do that. https://www.diystompboxes.com/smfforum/index.php?topic=120628.0

[vigilante397]

Cross-posting from pictures thread and the dedicated OmniBox thread, but this thing is finished. Nixie power supply feeding Alembic F-2B preamp with a 6N17B, simple cabsim v2, NE5532 headphone amp to 1/4" out, DI transformer to balanced XLR out. SMD except for the linear regulator and schottkey (didn't have any SMD yet), trimpot (SMD trimpots are weird), filter cap (10u/250V SMD cap? no thanks), and tube (duh).





Soldered without my left thumb, using index and middle fingers for tweezers, please don't judge the soldering too harshly