fuzzcentral DS-1 Mod build report

scottosan · February 08, 2005, 12:09:42 PM

Last night I bought a shiny new DS-1 and rushed home to tear the guts out and the Fuzzcentral DS-1 hybrid "based off the ultra and seeing eye mod". The mod went smooth and I finished rather quick. I was really excited, turned on my amp and........... It sounded pretty bad. I was getting a bunch of bass distortion and it sounded really flubby and the gain characteristics were definately not "Keeleyeque". I double and triple checked my soldering joints and values and everything was good. I switched c2 from .1uf back to the original value 0.47 in a metal film. This really helped balance the tone, but the distortion was to "ice-picky" for my liking. I took out the red-led used to replace D5 and after a couple taste tests, I used a 1n34a germanium diode in D5. It was getting there, I then removed the suggested 47pf cap across D4 and D5. Has anyone else had experiences with the fuzzcentral ds-1 mod?

jimbob · February 08, 2005, 12:22:48 PM

I just did mine too and need to change the input cap - a little too bassey. Mine turned out sounding really good otherwise but I also changed and socketed ic and used the NE5532. That Really made a difference! Give that a try. Did you use those expensive Digikey parts or more common values and parts?

jimbob · February 08, 2005, 01:27:35 PM

Heres some more of the info-
Post subject:

--------------------------------------------------------------------------------

OK. finished the ds-1 but w a few changes. in comparison to axis central site of Phillips.( Awsome btw!!! Give it a look!!!!!!) anyway, i took his mods and experimented with the different values I had and came to my own conclusions.
513-NJM5532L - now that SIP worked great!!! Sounds So much better than the stock!!! .49 $ is all..and the price of the 8pin Dual op amp . NJM chip.

For the 1 ufs I used the blue box ones from RDV, most the resistors were either carbon film or metal. The caps were Polypropylene Capacitors for the pf's (very small box type) a greenie, and Poly film.
here the few diff I made-

I socketed the chip- Used a njm5532 per AMZ idea. Sounded Alot better!
r-12 was 2.2k
5mm red for the d5
Replaced the led indicator w a Bright Blue 5mm led (drilled it our) -easy - placed on led board and screwed back on. It sits there nicely.
r-39 22k instead of 20k
r-14 1k
r-2 610k ( might go back to 470 though)

Fret Wire · February 08, 2005, 01:46:59 PM

I've found with the NE5532, the 47pf cap needs to be lowered in value. The 5532 sounds nice and quiet but can sound a little rounded off treble wise. Basically, the input cap and smoothing cap across the diodes should be adjusted to your preference/rig/ears.

As far as caps, even greenies will sound better than the factory caps.

Jimbob: Did you have any interference with the socket and chip? It does sit right above the input jack. I just solder it directly in now.

jimbob · February 08, 2005, 01:59:15 PM

I never did the 47pf cap but ill give a try soon . As far as the socket and chip went there was no problem. I was really carefull to remove and re-install the socket/s. It was actually 1 millmax machined dual 8 pin cut in half and soldered in seperately. I did just go ahead and solder in the red 3mm diode in place as it sits there more firmly than when i socketed it. I dont recommend anyone to socket the red diode -esp with individual machine pinned sockets. This is cause the leads on the leds 3mm's are larger than the hols and although they may get to fit- its a tight fit and you might bend /break the solder joints, board, and socket leg while trying to get it to fit. I think i will socket the input cap and try different ones that will match to my set up a little better.

Ed G. · February 08, 2005, 06:53:35 PM

I wonder if the sip 5532 would work in the metal zone. I've got one given to me that isn't working and I'm sure it's one of the opamps. Man, those things stock are the most fizzy pedals I've ever heard but I wonder if it could be refined into something useful.

jimbob · February 08, 2005, 06:57:12 PM

Mt-2 works well for a FEW things and thats after some tweeking and a Eq or 2. Ed- giver a try. Im seriously thinking the world needs some info out theere bout this one --and i think im going to open it up soon and experiment. Then- Give all the results out to anyone who wants them or takes the time to read the page.

Hal · February 08, 2005, 07:42:14 PM

didnt really read the replies, but anyway, I did those mods, and I love them :-D. No weird flabby sounds for me.

I have a DS-1 from around '96, with a different op-amp and one different resistor than the newer ones.

KORGULL · February 08, 2005, 08:17:47 PM

scottosan wrote

Quote........... It sounded pretty bad. I was getting a bunch of bass distortion and it sounded really flubby and the gain characteristics were definately not "Keeleyeque".

QuoteHas anyone else had experiences with the fuzzcentral ds-1 mod?

I did the Fuzz Central mods. Mine turned out pretty much like yours - way too much low end and not-so-smooth distortion.
My pedal doesn't have the same IC in it that the mods were created for, but all the components matched up except C7 - mine had a 100pf disc instead of the 10pf that is on the list.

Here's what I did (after the mods) to improve the sound:
Changed C3 to .068 metal film. (stock value was .047uf/mod value was 0.1uf)
Made C4 (about) 260pf mica.
Those two changes tamed the bassiness.
Made R14 2k2 metal film (stock value was 2k4/mod value was 1k5) - this really seemed to improve the distortion characteristics.

I tried germanium diodes, LEDs, and the stock diode again before going back to the LED. After the above changes were made the LED sounded pretty good. At first I thought the LED was the cause of the bad distortion sound but I believe the main culprit was the R14 mod change.
I left the 47pf cap across the diodes. Sometime maybe I will remove it and see if there is much of a difference.
I think a toggle switch to choose between an LED and a germanium diode like I've seen some people do is a good idea to try too.
In the end I do think the pedal sounds better now - it certainly isn't thin and trebly like it was when I first got it.

MartyMart · February 09, 2005, 08:06:06 AM

I agree with Korgull, C3 at 0.68 works well and I left R14 stock, as there was more than enough "drive" and "gain" increase from using LED's !!
Using one 3mm red LED and one 1N4001 was what I settled on for clipping diodes, thats quite a nice combo.
I didn't enjoy 1N34a/1N4001 as a pair quite as much, it sounded a bit "soggy"

Marty.

AL · February 09, 2005, 08:48:30 AM

One thing to keep in mind when doing the mods - To my knowledge Phillip plays through a Fender twin and he just showed a picture of his Telecaster. That's a lot of high end, so if it sounds muddy or has too much low end it probably sounds on the money for the Fender set up. Just a thought.

AL

KORGULL · February 09, 2005, 06:54:15 PM

MartyMart:

QuoteUsing one 3mm red LED and one 1N4001 was what I settled on for clipping diodes, thats quite a nice combo.

1N4001 you say? I didn't think to try that one - have to give it a shot.

Prive · February 10, 2005, 01:26:38 AM

What IC comes with that DS1 i have similar problems and the IC isn't none of Keeley's mod says.

Saludos, Marcelo.

KORGULL · February 10, 2005, 10:22:30 PM

The IC in mine is called a BA728N.
I bought the pedal about 3 years ago.
It is made in Taiwan.

News:

fuzzcentral DS-1 Mod build report