ruby troubles

[birt]

i just made a ruby amp.
when i turn it on the only thing i hear is a really quiet noise so i know it's on... i checked the wiring, everything seems ok, it just doesn't work

[javacody]

Well birt, the Ruby is a well tested design, it has to be either your soldering/wiring or a bad component. I've yet to have it be a bad component when an effect isn't working, not that it isn't possible, mind you. LOL It's usually human error at work.

Check all of your grounds. If you run the + wire from your input jack right into the 386 chip, do you hear any sound? Let's figure out if its the buffer, the chip, the input, or the speaker wiring.  

[birt]

i checked the wiring on the board and teh pots again, its all good.
and i took some voltage readings:
G:1,7v
D:8,93v
S:0 (a couple of milivolts actually...)

on the ic:
1:1,3v
5:4,4v
6:8,91v
7:4,5v
8:1,3v

all i can hear is a slight pop when i turn it on and then just a litlle hiss.
the normal sound when you turn on an amp.
only the signal isn't there.

[birt]

Well birt, the Ruby is a well tested design, it has to be either your soldering/wiring or a bad component. I've yet to have it be a bad component when an effect isn't working, not that it isn't possible, mind you. LOL It's usually human error at work.

Check all of your grounds. If you run the + wire from your input jack right into the 386 chip, do you hear any sound? Let's figure out if its the buffer, the chip, the input, or the speaker wiring.  

if i run the input directly in pin 2 of the chip it works (well, it doesn't sound really good that way cus i tested it with my ipod and a really tiny speaker  :lol: )

so it must be the buffer?

[birt]

i noticed i swapped gate and source so i corrected that.
now i can hear my guitar but really really quiet, too quiet

[RLBJR65]

Birt, do a forum search really it will help, I'm not trying to be a smart a**
alot of people have had the same problems your having and the answers should already be here.

[birt]

:oops:
when i corrected the fet-pinout i forgot to put the inputwire on the gate, it was still on the source..

but now it works!
with my 4x12 greenbacks it sounds really good, especially with a booster in front of it. better then most small ss amps i've heard.

time to put it in a nice box


oh, and is there an easy mod to give it a little more treble? a simple TMB tonestack maybe?

[javacody]

birt, if you add a tonestack, you are going to want an additional buffer. You will lose too much signal from the tonestack. Maybe use a Fetzer Valve?

Aren't JFET pinouts fun? What I love is when I figure out my own layout, and in drawing it all up, I get the pinouts wrong. Then when I'm populating the board, I have to twist the JFET all around. Looks real professional.  

Good job on finding your mistakes. Once you figured out it was the buffer, it didn't take long to troubleshoot, did it?

What kind of guitar are you running into the Ruby? It may also be your speakers that don't have the treble response that you would prefer. With an 8" Vintage Reissue Jensen, I had way too much treble. What kind of JFET are you using? You may also play with the capacitor values on the input and between the buffer and the IC.

[birt]

birt, if you add a tonestack, you are going to want an additional buffer. You will lose too much signal from the tonestack. Maybe use a Fetzer Valve?

Aren't JFET pinouts fun? What I love is when I figure out my own layout, and in drawing it all up, I get the pinouts wrong. Then when I'm populating the board, I have to twist the JFET all around. Looks real professional.  

Good job on finding your mistakes. Once you figured out it was the buffer, it didn't take long to troubleshoot, did it?

What kind of guitar are you running into the Ruby? It may also be your speakers that don't have the treble response that you would prefer. With an 8" Vintage Reissue Jensen, I had way too much treble. What kind of JFET are you using? You may also play with the capacitor values on the input and between the buffer and the IC.

well, i tested it with 4x12 greenbacks (16 ohm total so it'll probably be different on 8 ohm) with a guild s-300. ( http://users.pandora.be/vandijckheffen/bert/guild1.JPG )
i also tested it on litlle hifi speakers and indeed, too much treble that way  :lol: (and the plastic speakers distorted, kinda like a nasty fuzz sound)
i'll just leave it as it is.
i used a 2n5457.
what are cheap good guitar speakers? jensen? (because somebody asked me to build a ruby combo)

[javacody]

Jensen Ceramics are very inexpensive. My 10" ceramic Jensen Vintage reissue (I believe they are made in Italy now?) was about $30. It has a lot of high end though. Jensen 8" and 10" speakers tend to have much better high end than most guitar speakers, which can be a good and a bad thing.