Darkglass Microtubes B3K debug

[guidoilieff]

1.Name of the project: Darkglass Microtubes B3K debug

2.Links to the source of the project: http://effectslayouts.blogspot.com.ar/2018/05/darkglass-microtubes-b3k.html

3. (i'll try to upload pictures)

4. I tried j112,mpf102 and bf245a. Replaced 22nf capacitors for 33nf. Replaced 1uf capacitors for 2 680nf in parallel both times, 200k resistor (t2 Source) for 220k.

6.What it does and does not do how it works: Blend pot works, the dry signal is ok but volume drop in the wet signal A LOT. An electric bass don't make any sound after the first 1M resistor but an amplified signal does. It's not distorted and sound like I have my finger on the input or there is a ground disconnected, that kind of hum depending on the switching and pretty loud. Also  sounds very tiny (no bass).
Tried different transistors in all combinations possible.

I can't hear anything on the input of the first tl072 (pin 2 and 3) but in the output (pin 1) is that annoying sound I described for the rest of the circuit.


Voltages:

T1

G 0
S 2.4
D 4.7

T2

G 4.2   
S 4.7
D 9


4049UBE

pin1 6 v+
pin2 2
pin3 2
pin4 6
pin5 0
pin6 6
pin7 0
pin8 0 gnd

pin9 0
pin10 6
pin11 0
pin12 6
pin13 0
pin14 0
pin15 6
pin16 0

I don't know if Im missing any info.

Thanks for your time.

[anotherjim]

Can't tell much without a schematic. Do you have a link.
Some things I can see...
If T1 is an amplifier, it's probably ok.
If T2 is a buffer, it's probably ok.
If only one inverter in the 4049 is used as an amplifier (pin 2&3), it's probably ok.

[guidoilieff]

Can't tell much without a schematic. Do you have a link.
Some things I can see...
If T1 is an amplifier, it's probably ok.
If T2 is a buffer, it's probably ok.
If only one inverter in the 4049 is used as an amplifier (pin 2&3), it's probably ok.

http://guitar-gear.ru/forum/index.php?app=core&module=attach&section=attach&attach_id=29146 I think this will work and here is another one https://4.bp.blogspot.com/-AncwI2iyg2g/WM-9dFGc_cI/AAAAAAAAElo/JPPhsPyjavcasyIfRYj_0IRIf1cjaGBTgCEw/s1600/b3k.png

I don't know on which schematic its based on.

[anotherjim]

Let's say it's this one...

So there are those TL072's we don't have measurements for.
BTW, if you have it plugged into a high impedance amplifier, it's possible for some signal to sneak through circuits that actually have no power. It's also possible to get audio that's weak/noisy if the instrument input jack wiring has a problem.
You should expect to get good audio on all pins except power & ground of the first TL072 and the DC bias on the pins should be 1/2 of the 9v supply from VR connections.

[guidoilieff]

Let's say it's this one...

So there are those TL072's we don't have measurements for.
BTW, if you have it plugged into a high impedance amplifier, it's possible for some signal to sneak through circuits that actually have no power. It's also possible to get audio that's weak/noisy if the instrument input jack wiring has a problem.
You should expect to get good audio on all pins except power & ground of the first TL072 and the DC bias on the pins should be 1/2 of the 9v supply from VR connections.

Oh yeah, sorry. Forgot to mention that all tl072 voltages are ok. Also audio jacks are ok and I tried on 2 different pc speakers.


Here it is the schematic that its based on



I'm trying to understand the path of the input signal.... the audio splits from pin 6 and 7 to the blend pot and the gate of the first transistor right?



Sorry if i'm being a little bit messy with my info and my english...

[KarenColumbo]

The ...org Link you posted is jumbled.

[bluebunny]

The ...org Link you posted is jumbled.

The link is at "the other place".  You'll have to fill in the blanks yourself.

[KarenColumbo]

Ah, that one. Always forgetting it's an .org place. Btw: I'm building a b3k at the moment - for a friend. Will try these schems out tomorrow/day after tomorrow.

[guidoilieff]

The ...org Link you posted is jumbled.

let me fix that



you'll have to download the image for full res

[guidoilieff]

Does this help? A video will help? what should I do now?