small clone chorus for more warnth less hiss?

[hershey]

I built a tonepad small clone chorus which sounds great. From memory the analogman clone chorus was warmer and quieter. my clone has some background hiss and more top endy (also relative to bypassed tone). Anyway to  mod it for more warmth and less hiss? Or is the hiss inherent with inconsistent quality of bbd chips?
thanks in advance

[Fp-www.Tonepad.com]

"Hershey",

The small clone from tonepad is as warm and clean as can be. I have built it a few times and I always get the same results: warm extremely clean without any hiss or clock noise chorus.

You may have a wrong part somewhere.

Regards,
Fp

[Pushtone]

The Tonepad Small Clone Chorus project sounds GREAT! Don't know about AnalogMans but the sound of the TPSC is warm and lush as described and has more character than my DSP chorus. Fab project, thanks Fp.
But...
My Small Clone build is a little noisy too. A constant hissssss, that dosen't change even when the Depth pot is at minimum or maximum. I can get the hiss to be minimal by boosting the signal before the chorus and turning down the amp. Maybe I chose a poor IC?

Hum.. wrong parts eh?
Well, lets have a look.

I used...
Tonepad layout
Made PCB w/ PnP Blue + feric cloride
10k Depth pot mod.

These Transistors
IC1 - JRC4558D 4025B not sure where I got this from?? SB?
IC2 - 595-LM358AP    LM358AP    Texas Instruments Amplifiers DIP-8 Dual
595-CD4047BE    CD4047BE    Texas Instruments Multivibrators 14-Dip CMOS LP Mono/Astable
Q1 - 512-2N5087_J18Z    Fairchild Small Signal Transistors TO-92 PNP Transistor General Purpose    
Q2 & Q3 - 512-2N5088D11Z    Fairchild Small Signal Transistors TO-92 NPN Transistor General Purpose    
MN3007 from SmallBearElec.com
512-1N914    1N914    Fairchild Diodes DO-35 100V 4.0ns Diode Single Junction

Good resistors
Example (used one of these two brands for all values)
660-MF1/4CL1003F  KOA Speer 1/4Watt Metal Film Resistors 100Kohms 1%
271-180K Xicon 1/4W 1% Metal Film Resistors 180Kohms 1%

Lots of different Caps
140-XRL25V1.0  Xicon Radial Electrolytic Capacitors 25V 1.0uF 20%
140-XRL25V220  Xicon Radial Electrolytic Capacitors 25V 220uF 20%
140-XRL25V10 Xicon Radial Electrolytic Capacitors 25V 10uF 20%
140-PF1H473K  Xicon Radial Polyester Film Capacitors CAP 50V .047uF 10%
140-PF2A272F  Xicon 2% Radial Polyester Film Capacitors CAP 100V .0027uF
5982-15-500V180    CDE Mica Capacitors MICA 180PF500VJ
5982-15-500V100  CDE Mica Capacitors MICA 100PF500VJ
140-PF1H103K  Xicon Radial Polyester Film Capacitors CAP 50V .01uF 10%
80-T355C225K035    Kemet Dipped Radial Tantalum Capacitors 35V 2.2uF 10%
140-50S5-471J Xicon Ceramic Disc Capacitors 50V,SL,470PFD,5%
140-PF1H153K Xicon Radial Polyester Film Capacitors CAP 50V .015uF 10%
140-PF2A332F Xicon 2% Radial Polyester Film Capacitors CAP 100V .0033uF
140-PF2A333F Xicon 2% Radial Polyester Film Capacitors CAP 100V .033uF
140-PF2A472J  Xicon Radial Polyester Film Capacitors CAP 100V .0047uF 5%

The controls are even over their range. I can get a "chopper" noise out of it when RATE and DEPTH are both set to max, but this setting is extreem. Should it be silent even at this extreem setting?
Otherwise it just has a constant hiss.

I noticed that the Small Clone can take a lot of input level without breaking up. So I use a Minibooster or Orange Squezzer in front of it to boost up the juice, then I turn my amps master volume down. Hiss is gone and chorus sounds great.

Could there be a better choice for IC1? One with more input gain? I used a JRC4558.
Or a way to get more gain at the input?
Or maybe it's just because of sloppy soldering. I'll have to build another to find out for sure.

Pics of the PCB

http://www.primacoustic.com/pics/SmallClone-pcb.jpg
http://www.primacoustic.com/pics/SmallClone-pcb2.jpg

[nelson]

Arent most of the original EH pedals prone to noise? I am yet to build a TPSC but I def plan on building one. This thread is of interest to me, just incase I run into the same problem. However I fear that this is an inherent flaw in old EH designs.

[Pushtone]

...And some folks are pickier about noise.

The TPSC is no more noisy than my BOSS GE-7 EQ pedal. Totaly exceptable for a 9v pedal. I don't want ya'all to think the TPSC is bad noisy in any way.

But could it be better? Are there better choices as far as IC/transistors than the ones I used?

I've been using it for over a month now but is currently disassembled for painting. I will post back with a finished pic.

Here's another thread that I talked about troubleshooting the project.

http://diystompboxes.com/sboxforum/viewtopic.php?t=33445&highlight=

[Fp-www.Tonepad.com]

Mine is dead quiet...

I would suggest using a TL072 in place of the 4558 or even one of the high end dual opamps there.

Fp

ps: TPSC I like the sound of that

[nelson]

1% metal film resistors would be a good idea too.  

[Ed G.]

My small clone from tonepad's layout is dead quiet. I used metal film resistors, not sure if that made a difference. I use one of those high-end burr-brown chips in there, but I didn't notice any more noise with a 4558.

[Pushtone]

About the chopper noise at max knob settings...
Should the TPSC be totaly silent when the rate and depth controls are set to max?


Mine produces a "chopper" noise when idling and when playing through at this max setting. It would help to know if this is normal or not. Chopper noise goes away when both knobs are backed off by 25% (3 O'clock). Even with the controls backed off, the sound is intense with fast swooshing and swirling, a setting I would rarely use. In more tipical settings I hear the constant hiss.

Mine is dead quiet...

I would suggest using a TL072 in place of the 4558 or even one of the high end dual opamps there.

Fp

I have a couple of those, oh but they're JRC too  
I'll have to get a couple of different brands of TL072 just for my own experience.

[hershey]

I think the hiss may be due to the mn3007.
Ce-1 pedals varied in background noise apparently due to bbd chips. The one I havbe is dead quiet, where others I heard are hissy.
Yes I used metal film resistors and correct components. You need to have analogman chorus side side to compare, there is more warmth and fullness in tone in the analogman.

Nonetheless it still sounds great. Thanks FP!

[Fp-www.Tonepad.com]

Sure!

Hey, since you have one there, why don't you compare it with the schematic and see why that is. (and tell us, of course).

Fp