Search found 164 matches

by cpm
17 Apr 2013, 19:48
Forum: Capacitors
Topic: do power filtering caps need to be electrolytic
Replies: 4
Views: 9145

Re: do power filtering caps need to be electrolytic

By the way, i too would like to get a better understanding on what kind of caps are better for each situation, in a sensible and economical way. I'd like to go surface components as much as possible, and i guess there are some applications that would require some "kind" of caps to perform ...
by cpm
17 Apr 2013, 19:37
Forum: Capacitors
Topic: do power filtering caps need to be electrolytic
Replies: 4
Views: 9145

Re: do power filtering caps need to be electrolytic

somebody posted this about ceramic caps: http://my.execpc.com/~endlr/ceramic.html Says about the X7R class capacitors: These capacitors don´t have the good high frequency characteristics of Class 1 ceramics, they all show a drop in capacitance and a rise in dissipation factor as they go above 1 MHz....
by cpm
02 Apr 2013, 00:01
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Jordan Bosstone circuit analysis?
Replies: 2
Views: 2163

Re: Jordan Bosstone circuit analysis?

Q2 as a unity gain buffer - other than what is self implied, is anything else really relevant with it? I guess what I mean to say is if Q2 is omitted, the end result is primarily a higher output impedance? I know there are the clipping diodes on the output, but unity gain isn't really going to help...
by cpm
26 Feb 2013, 18:20
Forum: Stuff Seen for Sale
Topic: What could you do with Fasel Covers?
Replies: 7
Views: 3296

Re: What could you do with Fasel Covers?

CHEEZOR wrote:What can you do with them?
Fake fasel inductors
by cpm
18 Nov 2012, 21:35
Forum: Boutique Stompboxes dissected...
Topic: Rothwell Switchblade [traced]
Replies: 6
Views: 2661

Rothwell Switchblade [traced]

I had this box on the bench. The Rothwell Switchblade actually sounded nice, although a bit too bassy on the eq for my tase. The problem with this is that its kind of microphonic, a lot of gain and some supect smd electrolytics, and that its mounted soldered to the 3pdt, amplifying noises on the swi...
by cpm
14 Oct 2012, 22:51
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Ross Distortion [schematic]
Replies: 31
Views: 10627

Re: ross distortion...how could i screw this up? [schematic]

I'd lower the divider resistors from 1M to 100k or 10k... and connect the opamp ground to the lower strip, for a shorter path to Gnd
Also, the unused opamp looks to be latching to the rails, connect the input to Vref, instead of gnd

those changes should add some stability, just in case
by cpm
18 Sep 2012, 05:26
Forum: Stuff Seen for Sale
Topic: Another kickass European parts supplier
Replies: 5
Views: 3196

Re: Another kickass European parts supplier

i have a voucher code of 10€ that i wont use, and will expire short

for whoever may use it....
by cpm
03 Sep 2012, 11:37
Forum: DIY Stompbox designs
Topic: About voltage dividers
Replies: 4
Views: 1578

Re: About voltage dividers

actually that transistor you note is not a voltage divider. Its used there supposedly for "temperature stabilization" for the transistor array IC in which it is contained. I guess that is set to drive a current so it gets hot and "warm" the rest of the transistors in the package....
by cpm
24 Aug 2012, 16:50
Forum: Stompbox Builder's FAQs & How To's
Topic: Buffer theory/Knowledge show-off/Why IS that?
Replies: 3
Views: 3019

Re: Buffer theory/Knowledge show-off/Why IS that?

Try asking one of them to justify their purchase.
still more fun...
try asking one of those sellers to justify their selling price
by cpm
29 Jul 2012, 15:55
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Seymour Duncan Lava box [schematic]
Replies: 8
Views: 5425

Seymour Duncan Lava box [schematic]

This is a nice pedal, not expensive and can be faound cheaper os second hand A rotary 6 position switch to select some caps for tone shapping and amount of gain. Two bimos opamps driven into saturaion I was suirprised at how effectively it cleans with input volume variations, very sensitive. Most of...
by cpm
22 Jun 2012, 21:14
Forum: Modern Stompbox Effects (1975 - ...)
Topic: EHX - The Freeze
Replies: 31
Views: 21375

Re: Electro-Harmonix: The Freeze (Gut Shots for fun)

i noticed the spring on the daughterboard is nor connected to anything... i'd guess it was the to ground the chasis, but doesn't seem so...
by cpm
21 Jun 2012, 21:38
Forum: DIY Stompbox designs
Topic: my new delay, over the top PT2399's
Replies: 57
Views: 24979

Re: my new delay, over the top PT2399's

Thanks for the info. These components are all new for me, but I'm slowly starting to piece together the control flow. Just checking if I understand: For the bypass state, the 4027 stores the bypass state (based on the event of momentarily closing the SW_BYPASS pins), and its output is routed to one...
by cpm
20 Jun 2012, 21:36
Forum: DIY Stompbox designs
Topic: my new delay, over the top PT2399's
Replies: 57
Views: 24979

Re: my new delay, over the top PT2399's

I found this thread while going through the DIY designs and am so impressed by the sound that I'm considering building it, but some of the concepts in this project are new to me and I have a few questions: 1. To start with, I want to put together a list of parts, but I couldn't tell a couple of thi...
by cpm
04 May 2012, 08:14
Forum: Ready-To-Build Effect Projects
Topic: A Switching Scheme
Replies: 247
Views: 27589

Re: A Switching Scheme

Nowadays, there are very good quality single pole push switches available for much less than the nasty TPDT footswitches. I use "vandal proof" stainless steel push buttons that are designed for outdoor use. The ones I use are latching ones, but momentary ones are available for use with CM...
by cpm
29 Mar 2012, 23:11
Forum: Ready-To-Build Effect Projects
Topic: MXR Sustain - NOT the nasty Dynacomp!
Replies: 22
Views: 2717

Re: MXR Sustain - NOT the nasty Dynacomp!

is the noise from the OTA is smaller than the "in-path" topology because of it going for less gain? What about a OTA in the path, but settled at near-unity gain, and amplifying only the sidechain input. That would be the same noise as this ota-in-the-feedback, but one less opamp in the mai...
by cpm
29 Mar 2012, 21:52
Forum: Ready-To-Build Effect Projects
Topic: MXR Sustain - NOT the nasty Dynacomp!
Replies: 22
Views: 2717

Re: MXR Sustain - NOT the nasty Dynacomp!

but...
if the OTA is noisy by itself, it would still inject the noise in the feedback path, doesn't it?
by cpm
20 Mar 2012, 14:26
Forum: Electric Guitar Rewiring
Topic: Do no load pots actually "click" ?
Replies: 7
Views: 3971

Re: Do no load pots actually "click" ?

cant a regular guitar pot be modded into this no-load thing? if its open at the legs you can cut with a sharp knife the top track.
i remember doing it some time to a smaller pot for a pedal...
by cpm
08 Mar 2012, 10:44
Forum: Absolute Beginners
Topic: An aspiring circuit board designer who needs 2 know what do
Replies: 2
Views: 2255

Re: An aspiring circuit board designer who needs 2 know what

kimanistar wrote:I'm pretty sure I understand how they all work but I can't seem 2 figure how they relate 2 pedal design
:applause: :popcorn:
by cpm
28 Feb 2012, 23:48
Forum: Ready-To-Build Effect Projects
Topic: Fred Briggs - Super OCD
Replies: 63
Views: 9833

Re: Fred Briggs - Super OCD

The OCD tonestack is where it has its characteristic sound. If you change it there is no more OCD, imho, just a more generic clipper (as good as it can be)
Actually, i didnt like at all that OCD tone, way too bassy with my gear
by cpm
16 Feb 2012, 14:47
Forum: DIY Stompbox designs
Topic: DMM with 6xmn3008
Replies: 4
Views: 1556

Re: DMM with 6xmn3008

thats a very good chance to try it out by the OP, please test it on your breadboard and report back!