Build Your Own Clone Message Board

OK guys, this is more of a "2nd opinion" type post.

I built up a Madbean Cavedweller a week ago and substituted no parts, etc. The only thing I had different was the Pots (3 A50Ks)

After finishing the build, I really enjoyed the sound of it - UNTIL, I get past about 200-300ms, and this thing starts hitting me with a really really ugly annoying white noise in the background of my signal, just sitting there, even when I dont play.

I am thinking about making a video of the issue, or atleast a sound demo.

MY QUESTION: Has anyone built this circuit and had this issue?? Im just completely perplexed, and I know that if I try to give this to a musician it will come right back to my shop.

I'd go on his site and first read if there are any corrections. He has a sub forum that has fixes if an issue is found. If nothing there then check out the tech threads real quick. If nothing then post your issue there. I have a hard time believing that is the way it was designed.

Sorry to hear this Pat, but since you asked, I have built this and didn't have that issue.

It's a low-fi sounding device, I do have an issue with treble loss, but that's likely my build, but it functions a described and does offer a nice dark textural wash, I can't say it is particularly noisy though...
To quote the first paragraph of the build notes the delay "ranks as a “medium fi” type circuit, meaning that filtering of the PT2399 is kept at a minimum in favor of a small footprint. While you won’t get quite the fidelity of the Echo Base,for example, it still sounds very, very good and offers a somewhat unique flavor of delay"

It does get lo-fi at the extremes, so maybe your 'A' pots are exacerbating the issue, or possibly your chip is faulty?

I have built many (most) Madbean projects and think he does a splendid job.

I've built the cave dweller. You shouldn't have the noise your describing while not even playing. Something is wrong. You really only get some noise on the delay at 3/4 to full delay time. If you have a thread started at madbeans post your voltages of the pt2399.

Josh

+1. What you're experiencing is in no way normal. I'm sure the folks over at Madbean's (including ^this guy) can help you sort it out.

I've noticed that when I get unusual noise in a 2399, it's usually something related to the voltage supply to the IC. Double check that you are getting 5v on pin 1.

OK Guys!! Off to get some coffee and possibly sort this out!

5 volts on pin 1

Looks like everything is going to be ok!

Went and threw in a B25k minipot I got the other day from Smallbear, and I think I ahve the perfect 420-440 ms that I want out of a Delay ( I dont usually go over that )

This is great! I think possibly the A pots were screwing things up all together, I just have no b50ks to try with. I am waiting on a few from Count Zero though!

Until then, looks like I can sleep soundly with this circuit off my mind, I wont build this for anyone who wants long delays though!!

There's no good reason to use audio taper on a delay time pot. Linear is better suited for the task.

Very much agreed there, CJ!!!

When I get low on parts, I start winging and cutting corners, substituting - thats when problems happen!

I do that too! Unfortunately, that's usually when I dig into the bucket to pull out the ONE dead pot (or the 2, or 3...the last pedal I built had 2 dead pots because I pulled them out of an old stash and didn't check them first. Bah.).

We all do it.