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Hi guys! I am currently building a Muff’n and am building the ‘Ram’ version. C1 is listed in the BOM as a 10uF cap. I have Tantalum (polarized) version of the 10u but according to the schematic, the 10u called for is a bi-polar cap. So my question is, can the Tantalum cap be used in that location?
Thanks, in advance!SteveO
P.S. Doing a quick internet search I couldn’t locate any 10uf’s that weren’t polarized…
Hi Steve,
Yes. Tantalum caps are bi-polar. They are usually marked with a + for the anode sand quite often that lead is longer as with an LED.
Cheers
Thanks ‘fig’… I am aware that the Tantalum caps are polarized, my question is can that Tantalum cap be used in the C1 location on the Muff’N PCB?
Apologies Steve.
Yes, you can use an EC or tantalum there. Orient it with the cathode to R1.
Cheers.
Correct. That’s my understanding. Perhaps an admin would confirm or correct that understanding for your peace of mind. Best of luck with the build.
Cheers
I would not use a Tantalum. Get it wrong and there could be fireworks.
Use a 1uF at C1. I believe 1uF is a typo I have to fix.
ACTUALLY . . . . . C1 is a 100nF, 120nF or 1µF cap – depending on which variant is being built. I’ve built a number of Muff’Ns and used the 100nF without issue on all of them. The “RAM” variant calls for a 1µF at C1and can be an MLCC, a box film or a non-polarized electrolytic.
See? Better answers!
Still, now I have to breadboard this to see if I was right….I’ll be sure to have the camera going, LOL!
Thanks guys. Best Steve.
I guess if I looked further across the page, I would have noticed the values of the other C1’s and figured out that it might have been a typo. Lesson learned. 😉
Thanks again everyone!
http://www.bigmuffpage.com/Big_Muff_Pi_versions_schematics_part2.html
The third schematic down on this page shows that it is a 10uF. I bet you that there’s no way you can tell the difference between 1uF and 10uF though. The only reason to go with 10uF Would be for “exactly matching” purposes. It’s not gonna sound any different than a 1uF.
I think that if you go through and read a lot of the pages dedicated to the big muff pi, you’ll find that some small variations exist within each variant. I think that some have speculated that this was because of part inventory on hand or because a slightly different value came in at a better price point for the manufacturer when they made a particular production run.
I would be remiss if I did not point out the “Official Schematic” hand drawn from the same link as above shows a value of 1uF for C1 dated Oct 15/1975 which is Rams Head because of THIS. BYOC and General Guitar Gadgets interestingly all have the same typo as well.
Also no mention of changing the value to 10uF anywhere. I would find that odd if it were not a typo.
Wilkie1 pointed out that 1uF gives you Bass frequency to 3hz.
Guitars do not reproduce 3hz (movie theater rumble) let alone what 10uF would drop that to so it is kind of a ridiculous value. I will make a note of that in the document.
I have no doubt that units of the Rams head were produced with both values within that variant. That was my point. Either should work fine. I think that each of the schematics listed on the big muff page different examples of the same variant but show different parts because that’s what they did back then. On that page they list several Rams head units’ schematics. If they all matched then there would be no reason for them to show more than one schematic. Both are correct in my opinion. For what it’s worth, I do agree with Barry that the circuit does not make the low movie theater rumble sound, and therefore does not require a 10 µF capacitor.
Yes I agree with Bruce in that I saw this original Muff Rams Head dissected that had 10uf caps at C1, C2, C13, a .05uf cap at C7 and a .0068uf tone cap at C8. So EHX shoved whatever they had in stock on any particular day (which Bruce already mentioned) for the coupling capacitors since lower frequency did not mean anything as it was all below what was required for guitar or Bass.
That said IMHO the actual important things to consider are:
- 10uF electrolytic can possibly go bad. (as in the thread above)
- 10uF caps are hard to find in other capacitor materials.
- Don’t use a Tantalum unless you are 100% sure of the orientation
- capacitor values from 1uF to 10uF will make (0) sonic difference with guitar or Bass
If you are after copying an original only then there really is no true original based on the dissected build in the thread above as well as the iterations covered by kitrae.
At the end of the day I would go with the EHX’s schematic and use a 1uf film cap. That type will last forever and has bottom end down to 3hz and if that is too boomy then substitute that for a 100n like most of the other variants.
Good advice Barry.
While breadboarding I came across a question: Is C15 (power stage) oriented correctly in the schematic? In other words, is that a positive + sign?
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