Death by Audio - Fuzz War

John Lyons · Post by **John Lyons** » 20 Jun 2008, 22:36

The Death by Audio Fuzz War is pretty cool and highly variable tone fuzz. Gets a nice scooped big muff all the way through Maestro fuzz tone and shin ei screaming fuzz type sounds. The tone varies but the fuzz is all out all the time.

I have a few pics of the top and bottom of the board as well as some shots with the board held up to a light so you can see the traces through the board.
I was going to trace this but I don't have the time right now.
If you want to trace from these pics let me know.

I only ask that you post them or let me see them when you are done

john

RnFR · Post by **RnFR** » 21 Jun 2008, 02:04

absolutely! i'd love to see what was goin on in one of their pedals.

salocin · Post by **salocin** » 21 Jun 2008, 07:06

Happy to trace if you post the photos.

Can't wait to see them! Have been quite curious about this one.

bajaman · Post by **bajaman** » 21 Jun 2008, 07:08

+1 - I will make a PCB and layout if enough interest is shown.
cheers
bajaman

briggs · Post by **briggs** » 21 Jun 2008, 12:51

Woooo, lets see those picks John. I find the Death by Audio stuff quite interesting

Bernardduur · Post by **Bernardduur** » 21 Jun 2008, 12:54

briggs wrote:Woooo, lets see those picks John. I find the Death by Audio stuff quite interesting

+1! Still want to find out what happens inside an Interstellar Overdrive

Bside2234 · Post by **Bside2234** » 21 Jun 2008, 17:47

+1. I would also like to have a look at the pics and give a go at tracing it.

e45tg4t3 · Post by **e45tg4t3** » 21 Jun 2008, 18:22

i also wanna see those shots^^... it sounding wonderful on the clips together with the tsa...

Benny

John Lyons · Post by **John Lyons** » 22 Jun 2008, 16:16

Here they are.
One of the pics (fuzzwar parts) has the cap values pots and transistors labeled.
Have at it!

Fuzz war trace1
Fuzz war trace2
Fuzz war trace3
Fuzz war trace4
Fuzz war trace5
Fuzz war trace6
Fuzz war trace7

john

culturejam · Post by **culturejam** » 22 Jun 2008, 18:22

John, you rule!

analogguru · Post by **analogguru** » 22 Jun 2008, 18:25

Thanks for the photos, but......

....I can´t believe it...... (beside the ugly, shitty pcb-layout):

A collector resistor of 180k and an emitter resistor of 390 Ohm, for what ? For 2,16mV across it ? You can ommit them.....

A collector resistor of 180k and a base resistor of 430k ?

BTW, are the transistors in the right orientation ? what is written on them ? manufacturer for pinout ?

five !!! of such transistor stages are cascaded, followed by a diode-clipper, a big-muff tone-control followed by another two transistor stages and a second diode clipper... that´s all.

Now you know where the name comes from:
By looking at the schematic of this "audio"-unit you can die by a heart attack - Death by Audio (schematic).

analogguru

John Lyons · Post by **John Lyons** » 22 Jun 2008, 19:45

Yes, the PCB layout is very ugly and pretty sloppy.
Sharp jagged traces and bad layout practices.
The input and output traces run parallel across the length of the board.
The traces are tiny in places for long runs and thick in others for only one component length.
Despite this it's not very noisy.

The tone control works a bit different than the big muff tone control.
It's low pass on one side and high pass on the other but there is quite a large sweep and it almost sounds parametric or similar to a zero through flange sweep when you rotate it fast across the sweep.

The Transistors are Fairchild branded so they are CBE.

I thought the clips sounded bad on the site but in person I liked this pedal.
It's a fuzz first and foremost, no "killer tone" here, just sonic mayhem heavy fuzz.
No octave down or other artifacts, just straight compressed fuzz.

john

analogguru · Post by **analogguru** » 22 Jun 2008, 20:14

It's a fuzz first and foremost, no "killer tone" here, just sonic mayhem heavy fuzz.
No octave down or other artifacts, just straight compressed fuzz.

That´s the big problem with Fuzzes:
Nearly with every shit you can achieve a (distorted) fuzz sound.

And this design is shit... The DBA-guy should visit an electronics school before he starts producing and selling.

Since I don´t want to waste my time by analyzing, here is the:
Death By Audio - Fuzz War schematic

As you can see, it is very temperature sensitive and if you would assemble R 19, the complete bias of this stage will be changed at higher levels.

Sorry that I didn´t draw jacks and switching for this junk.

analogguru

John Lyons · Post by **John Lyons** » 22 Jun 2008, 20:54

That was fast AG!

Can you explain how it's temperature sensitive please?

john

celadine · Post by **celadine** » 22 Jun 2008, 20:58

And this design is shit...

Since I don´t want to waste my time by analyzing, here is the:
Death By Audio - Fuzz War schematic

Thanks for the schem anyway!

Yeah, the circuit is far from restaurant quality. But, at least it isn't another tubescreamer clone.

analogguru · Post by **analogguru** » 22 Jun 2008, 21:41

Can you explain how it's temperature sensitive please?

In short:
Every transistor stage is temperature sensitive.
As a countermeasure you have the possibility of current feedback or voltage feedback.

Current feedback is achieved by a resistor between emitter and ground. The resistor must be significant compared to the collector resistor - 180k to 390 ohm is a relation of 1 : 40000 and therefore not significant.

Voltage feedback is achieved with a resistor between collector and base - like it can be seen in an EH Big Muff Pi stage. (If the collector voltage increases, the base voltage gets higher too by this reducing the collector voltage).

As you can see both methods are not used. To critisize is also the high collector resistor value of 180k resulting in a low collector current causing noise and the selection of a wrong base resistor.

analogguru

John Lyons · Post by **John Lyons** » 23 Jun 2008, 00:37

Ok, I see. Thanks for the explanation.
So this makes the circuit sensitive to ambient temperature?

EDIT:
I forgot about the clipping (or lack of) in Q6.
So those diodes and R19 aren't even in the circuit are they?
I wonder if that was something they did initially and just cut out R19 afterwards?
You can see leads soldered in the holes even.

John

soulsonic · Post by **soulsonic** » 23 Jun 2008, 00:54

That bad soldering really kills me. Those pedals are WAY too expensive to be built so poorly. That's total disrespect for the customer.

bajaman · Post by **bajaman** » 23 Jun 2008, 01:10

That bad soldering really kills me

Perhaps they were running low on solder

bajaman

Fuzzer · Post by **Fuzzer** » 23 Jun 2008, 03:36

bajaman wrote:
That bad soldering really kills me
Perhaps they were running low on solder
bajaman

HAHAHAHA.

Death by Audio - Fuzz War [traced]