Search found 28 matches

by Jim777
09 Oct 2007, 22:16
Forum: Boutique Stompboxes dissected...
Topic: Lovetone - Brown Source [traced]
Replies: 49
Views: 27992

It would be interesting to know why it was designed like this. The other odd thing is the very low input impedance at 220 ohms. Maybe it was designed 'by ear'.
by Jim777
09 Oct 2007, 18:38
Forum: Boutique Stompboxes dissected...
Topic: Blackstone Appliances - Blackstone Mosfet Overdrive
Replies: 51
Views: 16328

I remember someone commenting on this saying it was like the Obsidian but with N channel mosfets and some steps taken to lower noise.
by Jim777
07 Oct 2007, 17:33
Forum: Boutique Stompboxes dissected...
Topic: Lovetone - Brown Source [traced]
Replies: 49
Views: 27992

Tried it again and still got 1.5khz. I'm assuming 470n is the correct value? On Analogguru's schem he has 47n which gives 15khz. What I think it will do is give max gain half way between the two at approx 650hz falling off at 6db/octave either side. However, because the cut is quite severe it's goin...
by Jim777
06 Oct 2007, 22:04
Forum: Boutique Stompboxes dissected...
Topic: Lovetone - Brown Source [traced]
Replies: 49
Views: 27992

If I have this right the 470n cap and 220 ohm R will start cutting bass from 1.5 khz. The treble cut at max gain will be from 185hz :shock:
by Jim777
03 Oct 2007, 18:29
Forum: Boutique Stompboxes dissected...
Topic: Zvex - Box of Rock [traced]
Replies: 383
Views: 169010

I don't see the similarity between the BOR and the BSIAB. :? The more I look at the SHO the more convinced I am that the idea came from a big muff stage. And the suggestive name :wink: Mosfets bias up very similar to a bipolar transistor. The BOR looks more like a mosfet big muff without the diodes.
by Jim777
16 Sep 2007, 23:49
Forum: Boutique Stompboxes dissected...
Topic: Fulltone - OCD [traced]
Replies: 622
Views: 282023

OK back on topic....I havn't tried this internal diode mosfet thing yet does it sound any different to a bog standard diode?
by Jim777
16 Sep 2007, 00:50
Forum: Boutique Stompboxes dissected...
Topic: Lovepedal - Octave Planet (modded)
Replies: 48
Views: 14850

It's not going to vibe much with just 2 stages is it? Stating-the-bleeding-obvious quote of the week. :wink: I said they sound shit as a vibe substitute because on his own website , Sean states :- The MOST ACCURATE and righteous Uni-Vibe sounds to be had in a package this size. Half the size of the...
by Jim777
15 Sep 2007, 11:20
Forum: Boutique Stompboxes dissected...
Topic: Lovepedal - Octave Planet (modded)
Replies: 48
Views: 14850

It's not going to vibe much with just 2 stages is it?
by Jim777
14 Sep 2007, 10:22
Forum: Boutique Stompboxes dissected...
Topic: Crowther Audio - Prunes & Custard
Replies: 173
Views: 75745

Maybe there's an earlier version with 2 extra diodes and resistor?
by Jim777
13 Sep 2007, 21:19
Forum: Boutique Stompboxes dissected...
Topic: Fulltone - OCD [traced]
Replies: 622
Views: 282023

The OCD has a 470k input resistor. So why not 1meg or higher? Probably because that's what's in the voodoolab. You could easily raise the value of that resistor and I'm sure you would hear a difference. How would a 10meg pulldown resistor turn it to mud? Are you saying it has a different effect beca...
by Jim777
13 Sep 2007, 13:46
Forum: Boutique Stompboxes dissected...
Topic: Zvex - Box of Rock [traced]
Replies: 383
Views: 169010

Very nice layout thanks. I wasn't aware of that Kicad program it looks interesting.
by Jim777
13 Sep 2007, 02:23
Forum: Boutique Stompboxes dissected...
Topic: Crowther Audio - Prunes & Custard
Replies: 173
Views: 75745

It used to be quite common for some jap pedals to have an 11volt zener at psu input to protect from over voltage.
by Jim777
11 Sep 2007, 14:12
Forum: Boutique Stompboxes dissected...
Topic: Fulltone - OCD [traced]
Replies: 622
Views: 282023

by Jim777
10 Sep 2007, 00:39
Forum: Boutique Stompboxes dissected...
Topic: Crowther Audio - Prunes & Custard
Replies: 173
Views: 75745

Theblackman said he measured the 56k so I assume it's ok. I have doubts about a couple of things. The two 10k resistors coming from +/- of the second opamp to the 10u cap. On the pic they look like red red black black. 220ohms? The 10k resistor from the wiper of the level pot looks like brown black ...
by Jim777
10 Sep 2007, 00:15
Forum: Boutique Stompboxes dissected...
Topic: Ashbass - FUZZbrite
Replies: 52
Views: 18592

The box looks nice :lol:
by Jim777
08 Sep 2007, 01:35
Forum: Amplifiers
Topic: Zvex - Nano Head
Replies: 220
Views: 172067

by Jim777
07 Sep 2007, 18:50
Forum: Boutique Stompboxes dissected...
Topic: Crowther Audio - Prunes & Custard
Replies: 173
Views: 75745

Looks good. Where did you get the extra 2 diodes and 10k resistor from? I can see on the board where they could go. Were they fitted originally?
by Jim777
06 Sep 2007, 13:16
Forum: Transistors
Topic: Russian Article about Fet tube emulation.
Replies: 24
Views: 15346

There's some interesting stuff here about tube emulation http://www.pritchardamps.com/pritchardamps.cfm
by Jim777
06 Sep 2007, 13:12
Forum: Transistors
Topic: Russian Article about Fet tube emulation.
Replies: 24
Views: 15346

Oops it's there just not in the translated one :roll:
by Jim777
06 Sep 2007, 13:10
Forum: Transistors
Topic: Russian Article about Fet tube emulation.
Replies: 24
Views: 15346

I have that page from a few weeks ago there was a complete schematic of a preamp at the bottom of the page that isnt there now.