Author Topic: Muddy Sustain  (Read 991 times)

carp0824

Muddy Sustain
« on: April 02, 2017, 06:59:03 PM »
Hello all! I am brand new to building effects pedals for fun. I tried my hand at a circuit that was based off of the Electra Guitar. You can find the link to the build instructions www.premierguitar.com/ext/resources/files/DIY-PDFs/Oct14_PGDistortion_BuildGuide_Final_R2.pdf . The problem I have is that when I test the circuit on a breadboard my sustain is very muddy and the note no longer sounds like the note I played. All notes sound very good up until I let it ring out. Any ideas as to why this is happening?

The parts I used are as follows:

*2N5088 Transistor
*1N4001 Diode
*1N34A Diode and 1N914 Diode (These two diodes are in series with the 1N4001 running parallel)
*.1uf Xicon Ceramic Disk Capacitor
*68k Xicon 1/4 w 1% metal film resistor
*4.7k xicon 1/4w 1% metal film resistor
*2.2m Xicon 1/4w 1% metal film resistor
*.068uf  100v Polyester Capacitor
*16v 22uf Xicon Radial Electrolytic Capacitor

Zounds!

Re: Muddy Sustain
« Reply #1 on: April 02, 2017, 07:25:28 PM »
Can you elaborate on what you mean by "muddy sustain"? Does the note sputter out? Or something else?

Also, folks will probably be able to help more if you can give voltages for the 2n5088 transistor!

carp0824

Re: Muddy Sustain
« Reply #2 on: April 02, 2017, 08:20:20 PM »
I purchased the 2n5088 transistor from Mammoth Electronics and their page doesn't give me the voltage.

As for "muddy sustain" - When I play a power chord (any power chord) and let it ring out, the tone of the power chord becomes and awful sound. I am no longer able to tell what power chord I played. It's like I detuned my guitar or played a bunch of random strings at the same time. It happens within seconds of playing the chord and letting it ring. I'm not sure how else to explain it other than "muddy."

robthequiet

Re: Muddy Sustain
« Reply #3 on: April 02, 2017, 10:27:42 PM »
Here is an idea: Can you take a photo of your circuit in the breadboard and upload it somewhere like imgur or postimage.org, then post the link in this thread? We can then take a look at the circuit and maybe something will stand out as a way to fix.

By taking voltages we want to know what the voltage is on each pin of your transistor when it is on the board. If you need a tip on how to get these posted by all means feel free to ask.

robthequiet

Re: Muddy Sustain
« Reply #4 on: April 02, 2017, 10:30:58 PM »
By the way, did you try the circuit with the potentiometer on the output?

Also, do you have R3 on the emitter leg of the transistor?
« Last Edit: April 02, 2017, 10:35:06 PM by robthequiet »

duck_arse

Re: Muddy Sustain
« Reply #5 on: April 03, 2017, 11:23:01 AM »
Hello all! I am brand new to building effects pedals for fun.
.....
*4.7k xicon 1/4w 1% metal film resistor
*2.2m Xicon 1/4w 1% metal film resistor
......

welcome to the forum, carp. do you own a multimeter?

your parts listed says 4k7, but the build docs (33 pages! they really didn't leave anything out of that, did they?) specify 470R. what did you actually fit?

and, 2.2m (m=milli) is a very different resistor to 2.2M (M=Mega). don't sweat it this time, but next time ......
"Nick's got one leg, and his name's Nick, so we called the horse Legless Nick" - Legless Nick's trainer, George Osborne, after the 4th at Kyneton.

carp0824

Re: Muddy Sustain
« Reply #6 on: April 03, 2017, 08:26:20 PM »
Thank you for the feedback. It looks like I jumped the gun a bit. I already pulled the circuit off the breadboard and soldered it to my perf board. I then attached the wires back to the breadboard and tested again. Here is the link to the picture of my circuit https://postimg.org/image/n7fjvzs3z/

I do have a multimeter.

The 470R was used strictly for the breadboard to connect the transistors emitter to ground as instructed in 2.12 on page 13 of the build instructions.

The 470R seems to be omitted from the instructions once the circuit is moved from the breadboard to the perf board as seen in section 4.06 starting on page 21.

The 4.7k resistor is used for the LED according to section 4.11 on page 24.