Tubescreamer Mod question...

[trumpus]

Hey,

I just received the parts i ordered from SB to mod my stock TS-9 RI using this diagram here:



I think i may have ordered the wrong capacitors, however.  I ordered Poly caps - mine look like brown chicklets of 2 different sizes, and are labeled on 1 side, but there is nothing to deonote polarity.  Was I supposed to order polarized caps?  The ones i ordered are the Panasonic ECQ-B from Small Bear.  They look like this:



While on topic, are there any other mods that can be done to this pedal - with details that i can find on the web (rather than send it off to be modded...)

Thanks,
Brian

[Dave_B]

The brown caps are fine.  The polys aren't polarized so stick them in however you see fit.  They have "224k" on them, right? 

Regarding further mods, try typing "tubescreamer mods" into the search box.  Lot'sa stuff to do.

[twabelljr]

     The thing I disliked most about my stock TS-9 was the annoying hiss with the gain up. The mod that took care of that was changing the input and output capacitors to MPSA18's. The pinout of a MPSA18 (E-B-C) is different from Original 2SC1815 (E-C-B). With the flat side up, carefully bend the center and right side leads around each other to switch positions. Follow Bellyflop's recommendation to search for other mods. There are quite a few different opinions and mods available.

[trumpus]

The brown caps are fine.  The polys aren't polarized so stick them in however you see fit.

So am i changing it from a polarized tantalum to a non-polarized, or were the tantalum caps non-polarized as well?

They have "224k" on them, right?

I actually have to different ones - .22 uf and 0.1uf.  The 0.22 uf have 4F3 and 224J printed on them; the 0.1 have 4F9 and 104J printed on them.

I think I must have found another site that had instructions to change these out as well - seeing as how i bought 2 different types.  So which should i use?

Brian.

[bancika]

Those caps are fine, 224J means 22 * 10^4 pF which is 220nF or 0.22uF. I used those panasonics in my TS build as well.
You need both 0.1 and 0.22, use 0.1 caps to replace .047 cap (keeley suggested mod) and other 0.1 is for replacing stock one IIRC. Two 0.22 are for replacing those tantals.
Tantals are polarized but you can always stick non-pol. cap instead of polarized one.

[Bron-Y-Aur-Stomp]

i changed the 51pF to 100pF in my TS-808 and got a big treble boost. i really liked that because it gave me the Cold Shot SRV sound i searced for when i started this build - good for shuffle tone 

[bwanasonic]

Just a note- I didn't like the results of replacing the tantalums in my vintage TS9. It seemed to take away some of the character of the TS and made for a more *generic* sounding pedal. I did like the results of replacing both of the electrolytic 1uf NPs with metal film, but as with the tantalum swap, the perceived difference could have been from an actual change in capacitance rather than cap construction (let alone the placebo effect).

Kerry M

[gulliver]

For what it's worth, I used this mouser part number for the caps on my TS-5 mod: 581-BF014D0224K

TS-5 Mod
R34 – 100 ohm [71-RN60D-F-100K]
R35 – 10K Carbon film [71-RN60D-F-10K]
Poly film caps 0.22mfd/35V [581-BF014D0224K]
*Circle on board is negative, plus on top of tantalum is positive.
IC Socket for easy swapping – [575-113308]
Popular chips:
JRC4558D – [513-NJM4558D]
LM833N – [511-LM833N]
RC4558P – [595-RC4558P]
NE5532 – [595-NE5532P]
RC4559 – [595-RC4559P]

[Bron-Y-Aur-Stomp]

http://www003.upp.so-net.ne.jp/kazuhee/eindex.htm

[trumpus]

You need both 0.1 and 0.22, use 0.1 caps to replace .047 cap (keeley suggested mod)

Which cap is this?

and other 0.1 is for replacing stock one IIRC

Which one is this?

changed the 51pF to 100pF

Which is this one?

As you can tell, i'm kinda a newbie.   A little help would be great!

Thanks,
Brian

[trumpus]

Just a note- I didn't like the results of replacing the tantalums in my vintage TS9. It seemed to take away some of the character of the TS and made for a more *generic* sounding pedal. I did like the results of replacing both of the electrolytic 1uf NPs with metal film, but as with the tantalum swap, the perceived difference could have been from an actual change in capacitance rather than cap construction (let alone the placebo effect).

Kerry M

Are the electrolytic 1uf NP's the smaller barrel looking ones?

Brian

[bwanasonic]

Are the electrolytic 1uf NP's the smaller barrel looking ones?

I think both of them are marked by "NP" on the board and have the value marked on the cap.

Kerry M

[brett]

Hi.

i changed the 51pF to 100pF in my TS-808 and got a big treble boost.

The 51pF cap reduces high frequency gain (out in the RFI region).  Yes?
Increasing that cap from 51pF to 100pF will reduce high-end treble (by doubling the negative feedback of high frequencies).  Maybe at frequencies too high to notice.
I'm not saying you imagined the increase in treble, but any increase in treble wasn't due to this mod, and the imagination is an amazing thing.
cheers

[twabelljr]

     I've illustrated some of the typical mods. so they will be easier to understand. I do recommend getting a copy of the schematic and learning the resistor color codes so you can trace out the circuit on your board and understand what is going on. Read R.G.'s "Technology of the Tubescreamer" for circuit explanation and gain calculating formula. The 4.7k resistor and the .047uF cap form the RC filter. Changing these affects the frequency roll-off into the clipping circuit. See the AMZ "Fat Mod." and use the AMZ RC calculator to determin freq. roll-off with different combinations. Hope this helps.

http://www.geofex.com/Article_Folders/TStech/tsxtech.htm

http://www.muzique.com/lab/fatt.htm

http://www.muzique.com/schem/filter.htm

[trumpus]

     I've illustrated some of the typical mods. so they will be easier to understand. I do recommend getting a copy of the schematic and learning the resistor color codes so you can trace out the circuit on your board and understand what is going on. Read R.G.'s "Technology of the Tubescreamer" for circuit explanation and gain calculating formula. The 4.7k resistor and the .047uF cap form the RC filter. Changing these affects the frequency roll-off into the clipping circuit. See the AMZ "Fat Mod." and use the AMZ RC calculator to determin freq. roll-off with different combinations. Hope this helps.

http://www.geofex.com/Article_Folders/TStech/tsxtech.htm

http://www.muzique.com/lab/fatt.htm

http://www.muzique.com/schem/filter.htm

Thanks for all that great info!

Just a few follow up questions.  SO i've already done the 808 mod (470 --> 100, 100K -->10K and the Chip upgrade).  I went to radioshack last night and grabbed whatever i vcould for the other mods (in addition to the 0.1 and 0.22 uf poly caps i already had).  I couldn't, however, find a 1 uF poly film cap that would fit in place of each of the electrolytics.  The 1uF they had was HUGE.  Does smal bear have smaller ones, or will i just have to make them fit?  I also picked up a 100pF ceramic disc capacitor to swap out for 51pF cap that is stock

Additionally, could you recommend some other diodes that sound good?  I don't know anything about them, and it seemed that they came in different voltages and had different 1N____ numbers.

Finally - does anyone have any comments on the suggestion above to swap the in/out caps to MPSA18?

Thanks for all of your help!  I really appreciate it!

Brian

[Melanhead]

the Panasonic Polies from digikey work well ro replace 1uf np electros.

Part number P4675-ND

A lot of modders prefer them because of their small size ...

[R.G.]

You know, I was always a sucker for a guy who could tell the difference in a 98% of vintage Italian Wah sound and 100% of vintage Italian Wah sound.   

[$uperpuma]

You know, I was always a sucker for a guy who could tell the difference in a 98% of vintage Italian Wah sound and 100% of vintage Italian Wah sound.   

[Melanhead]

You know, I was always a sucker for a guy who could tell the difference in a 98% of vintage Italian Wah sound and 100% of vintage Italian Wah sound.   

Somehow I knew that was coming ... 

[trumpus]

You know, I was always a sucker for a guy who could tell the difference in a 98% of vintage Italian Wah sound and 100% of vintage Italian Wah sound.   

Huh?