RAM Head Muff modded by BJF!

picassochild · Post by **picassochild** » 18 Dec 2007, 15:08

Hey, guys, what do you think about this mod?

https://cgi.ebay.com/BJF-Electro-harmon ... dZViewItem

The Rotagilla · Post by **The Rotagilla** » 18 Dec 2007, 15:19

I think either Yun or AMZ posted it awhile back. Not sure who to credit.

analogguru · Post by **analogguru** » 18 Dec 2007, 15:35

People are really sick: $305,-- for a non-original BMP - Ram....

I don´t understand why BJF didn´t assemble a DIY-board when he used 2N 5087 instead of the original transistors..... sorry, I forgot the (possible) carbon-comp resistors...

analogguru

AL · Post by AL » 18 Dec 2007, 16:10

I've worked on one Ram's Head. It was/is the best sounding Big Muff I've heard. If I had one I wouldn't mess with it except to do some basic, needed maintenance.

AL

alteredsounds · Post by **alteredsounds** » 18 Dec 2007, 16:35

I've got several muffs of different eras, styles etc (

) but to my ears the Rams head is the worst sounding. The green russian is to my ears the nicest.

AL · Post by AL » 18 Dec 2007, 18:48

alteredsounds wrote:I've got several muffs of different eras, styles etc ( ) but to my ears the Rams head is the worst sounding. The green russian is to my ears the nicest.

Wow !! Complete opposite view here. Different ears = different tastes. I hate the Green version. We shouldn't play in a band together - we'd be too busy yelling at each other to turn down the racket.

AL

Dirk_Hendrik · Post by **Dirk_Hendrik** » 18 Dec 2007, 19:16

alteredsounds wrote:I've got several muffs of different eras, styles etc ( ) but to my ears the Rams head is the worst sounding.

I may assume you replaced the electrolytics? They tend to be totally dead after some 30 years, giving an incredible lack is sustain and drive and result in a very crappy Muff.

In personal taste I go with Al. A good, reconditioned rams head, is pure pedal porn in my subjective taste.

analogguru · Post by **analogguru** » 18 Dec 2007, 19:38

In personal taste I go with Al. A good, reconditioned rams head, is pure pedal porn in my subjective taste.

Personally I have a little problem with this "recapping-saga"....
It can occur that several types of electrolytics don´t last very long...

I had to recap the SMD-electrolytics in a (was it a Hartke?) bass-amp from the 90´s.
On the other side I recently had to service a Crumar Multiman-S (keyborad) from the 70´s and there was not a single electrolytic to replace. The trimpotis were the only problem.

So this general tendency to recap everything appears to me a little bit like:
"I don´t know what is the failure so I will recap everything...."
this is BS.... first secure that there is not another failure causing the problem and - maybe - then start searching for faulty electrolytics....

Please explain me:
After "reconditioning" what remains left, what cannot be assembled in a new board... ?

The pcb has been mounted in a new case....
This can be done with a new pcb too....

Then the transistors have been changed to 2N 5087.....
They can be assembled in a new board too....

Then the electrolytics will be replaced....
The new one can be assembled in a new pcb too...

The remaining parts are the:
pots, resistors, diodes and eventually ceramic caps....

Do you want to tell me that they are responsible for the sound ?????

Better do it like Jeorge did it:
Make a nice case, a new pcb, a mojo-IC what is a transistor-array and name this thing: "Stolen Nickle" (ah... sorry "Swollen Pickle")

analogguru

BJF · Post by **BJF** » 18 Dec 2007, 19:50

Hi,

OK the story goes as follows. The owner of this unit had a Big Muff that he had picked from many and liked this one the best but the EH casing would threaten to fall apart and it would be hard to use live from this so would I rebox this in a supplied box and at the same time make this effect work from standard supply of +9V and through a 2,1 Marushin jack? Normally I'd say no to any such work but thought it might be fun for once andexamining the circuit I decided to match a set of transistors of NPN variety close in hfe and hie and cm for each position and replace or flip any polarized component and unit recieved truebypass , the 2,1 Marushin jack and since I have never really liked the T-filter type used as tonecontrol for the Big Muffs I made a midrange control by connecting a potentiometer to the LP side of the T filter the same way you would with a T-filter, if you are familiar with those.

The original transistors and original parts were ofcourse returned with the pedal aswell as with a schematic of both the original circuit and the changes done.

Have fun
BJ

Skreddy · Post by **Skreddy** » 18 Dec 2007, 20:01

The auction states that the 2N5087 transistors were the originals (PNP of course), and perhaps Bjorn switched them to 2N5088s? (Auction does not state exactly how BJ switched the polarity, but it can be assumed that he changed transistors to NPN types).

And of course ceramic caps make a huge difference to the sound, as do of course different diode types. Carbon comp? I use them 'cause I like them. I may stop just to get RoHS compliant, but that would be the only reason for me to do so.

This is a basic re-housing with a few "improvements." I don't see why BJ should have had to make a new PCB in order to perform this job.

Still with the hating. What's up with that? I see original Big Muffs go for big bucks on eBay, and this one would be expected to go for a lot, considering the owner's investment and subjective valuation of it.

BJF · Post by **BJF** » 18 Dec 2007, 20:02

analogguru wrote:People are really sick: $305,-- for a non-original BMP - Ram....

I don´t understand why BJF didn´t assemble a DIY-board when he used 2N 5087 instead of the original transistors..... sorry, I forgot the (possible) carbon-comp resistors...

analogguru

Hi,
Well you see some people want just that pedal.Besides the box was supplied. I don't believe in myths and could well have built one but am not that interested in building copies, but making an original work is another thing.I suppose there would be ample Big Muff copies around anyway to choose from but now this guy wanted just this one.
Oh it might have had some CC resistors not that it would matter much to the sound of a unit like this.
There would on the other hand be a point in getting very similar transistors of NPN variety to replace the PNP's it came with - do you think it would have sounded differently if I had reversed the supply instead?

No, I don't believe I'll get 305 USD from this pedal being sold on e-bay and it may not either tell what I actually asked for the work....
Changing the transistors and the polarities I felt was the most economical thing to do.........

Oh right, if I remember correctly the transitors I used were BC239C, BC549C, BC550C in all four transistors. These were picked to match the properties of the original transistors.

Have fun
BJ

analogguru · Post by **analogguru** » 18 Dec 2007, 20:11

There would on the other hand be a point in getting very similar transistors of NPN variety to replace the PNP's it came with - do you think it would have sounded differently if I had reversed the supply instead?

No, I don't believe I'll get 350 USD from this pedal being sold on e-bay and it may not either tell what I actually asked for the work....
Changing the trasistors and the polarities I felt was the most economical thing to do.........

Never say this loud when a "true believer" in the mojo FS37000 (or FS 36999) is around

Did you know ? The mystery FS36999 is nothing else than a custom stamped Fairchild 2N 5133 .....

analogguru

BJF · Post by **BJF** » 18 Dec 2007, 20:16

analogguru wrote:
There would on the other hand be a point in getting very similar transistors of NPN variety to replace the PNP's it came with - do you think it would have sounded differently if I had reversed the supply instead?

No, I don't believe I'll get 350 USD from this pedal being sold on e-bay and it may not either tell what I actually asked for the work....
Changing the trasistors and the polarities I felt was the most economical thing to do.........

Never say this loud when a "true believer" in the mojo FS37000 (or FS 36999) is around

Did you know ? The mystery FS36999 is nothing else than a custom stamped Fairchild 2N 5133 .....

analogguru

Hi

Mum's the word

Actually I'd look at the properties of the transistor more than what happens to be stamped on it and no, I didn't know FS36999 was a mystery.

have fun
BJ

Skreddy · Post by **Skreddy** » 18 Dec 2007, 20:35

analogguru wrote:
There would on the other hand be a point in getting very similar transistors of NPN variety to replace the PNP's it came with - do you think it would have sounded differently if I had reversed the supply instead?

No, I don't believe I'll get 350 USD from this pedal being sold on e-bay and it may not either tell what I actually asked for the work....
Changing the trasistors and the polarities I felt was the most economical thing to do.........

Never say this loud when a "true believer" in the mojo FS37000 (or FS 36999) is around

Did you know ? The mystery FS36999 is nothing else than a custom stamped Fairchild 2N 5133 .....

analogguru

Yeah; that's fairly well known (although there are some who mistakenly claim it's a BC239 or some such).

Another myth is that EH had those transistors custom stamped to hide their identity. Poppycock. EH simply used surplus parts at that time, most of which were 2-4 years old already; and the FS36999 probably came from some sort of TV-related company.

But it seems to me that the FS36999 was PNP? I don't recall for sure, but I think it was. Funny it sounds EXACTLY the same as a 2N5133 of the same era.

I've tried thousands of various 2N5133's, and trust me; the circa 1968 NOS versions have "that" something that none others have.

analogguru · Post by **analogguru** » 18 Dec 2007, 21:46

I've tried thousands of various 2N5133's, and trust me; the circa 1968 NOS versions have "that" something that none others have.

@BJF
Did I promise to much ?

The funny thing is - what only few mojo-people know - that NPN and PNP transistors of that era had different characteristics.... even when they were sold as complementary.....

analogguru

BJF · Post by **BJF** » 18 Dec 2007, 22:31

analogguru wrote:
I've tried thousands of various 2N5133's, and trust me; the circa 1968 NOS versions have "that" something that none others have.
@BJF
Did I promise to much ?

The funny thing is - what only few mojo-people know - that NPN and PNP transistors of that era had different characteristics.... even when they were sold as complementary.....

analogguru

Hi

Well analogguru, I wouldn't know if you promised too much....

Now let's have a look in the mojo box and what do I find but a James Bond transistor the CCS5084023 in a TO-106 capsule.......alas a little to low gain for this particurlar Ram's head.

But those do look nice hehehe

The transistors it came with, and I will say it was a fine sounding BM at that had hfe's around 440 ....and were a standard high beta type at the time of manufacturing and in TO-92 capsule

Oh yes, the BC239C's at least were from about the same era but they fitted nicely anyhow woohoo

Complementary applies only to some applications and doesn't necessarily mean exactly alike apart from opposite polarity. With a given transistor you'd easily find 20-30 other types that match but may have something completly different printed on them depending on what parameters would be important to the application.

Usually though with nonlinear amplification most important is the workingpoint and so the transfer at overload this is not specified by the parts manufacturers.
Another important thing is the gainbandwidthproduct much affected by cm and hfe and hie.

Oh yes you can find transistors that distort in a certain way in a given circuit and examine why too if it is important.

There are a couple of things that make the BM circuit somewhat stable in this and that's that none of the transistors run at maximum gain( unless hfe is low........) and then the two stages that would clip from running out of voltage also has clipping diodes.
This distorting on distorting makes saturated effect, compressing-actually if you'd lift the first diodepair there would be more midrange and more output but less compression and you'd be more at the mercy of the transistors used.

Hey Anaolog guru, you wouldn't happen to have a few variant schematics on the BM?
Perhaps could make a fun comparision and produce some hints...

Disclaimer
I'm not a real fan of the EH Big Muff, while I always felt EH made exciting and new effects, but unfortuantely such that would break down and in fact my first pedal ever was an EH Screaming Bird-served me well for a few years but it broke down once a month from how it was built like a birds nest and eventually I made a perfboard for it but by then I had no further use for a treblebooster.

Have fun
BJ

alteredsounds · Post by **alteredsounds** » 18 Dec 2007, 23:30

I havent changed the caps on the bm and to be honest wont because i like to leave the older pedals intact and virginal

Here's my more interesting muffs:

Heavily modded US muff, Old dlx, Green Russian, modded Black Russian, Rams Head, old LBM, Muff Fuzz and 1980 Muff. Any gut shots etc, just ask.

theehman · Post by **theehman** » 19 Dec 2007, 14:09

BJF wrote:Hi,

OK the story goes as follows. The owner of this unit had a Big Muff that he had picked from many and liked this one the best but the EH casing would threaten to fall apart and it would be hard to use live from this so would I rebox this in a supplied box and at the same time make this effect work from standard supply of +9V and through a 2,1 Marushin jack? Normally I'd say no to any such work but thought it might be fun for once andexamining the circuit I decided to match a set of transistors of NPN variety close in hfe and hie and cm for each position and replace or flip any polarized component and unit recieved truebypass , the 2,1 Marushin jack and since I have never really liked the T-filter type used as tonecontrol for the Big Muffs I made a midrange control by connecting a potentiometer to the LP side of the T filter the same way you would with a T-filter, if you are familiar with those.

The original transistors and original parts were ofcourse returned with the pedal aswell as with a schematic of both the original circuit and the changes done.

Have fun
BJ

Any chance you could post a schematic of the mod?

theehman · Post by **theehman** » 19 Dec 2007, 14:12

Skreddy wrote: But it seems to me that the FS36999 was PNP? I don't recall for sure, but I think it was. Funny it sounds EXACTLY the same as a 2N5133 of the same era.

fs36999 = NPN
fs37000 = PNP

Dirk_Hendrik · Post by **Dirk_Hendrik** » 19 Dec 2007, 15:31

analogguru wrote:Personally I have a little problem with this "recapping-saga"....
It can occur that several types of electrolytics don´t last very long...

I had to recap the SMD-electrolytics in a (was it a Hartke?) bass-amp from the 90´s.
On the other side I recently had to service a Crumar Multiman-S (keyborad) from the 70´s and there was not a single electrolytic to replace. The trimpotis were the only problem.

So this general tendency to recap everything appears to me a little bit like:
"I don´t know what is the failure so I will recap everything...."
this is BS.... first secure that there is not another failure causing the problem and - maybe - then start searching for faulty electrolytics....

Eeuh AG,

Where exactly did I say that I hadn't looked for other faults first?

But by hooking up the scope the problem was evident and the Electrolythics were done. Measured em as well. Then, when you have had something like 10 Muffs with the same symptoms and the same problem, might it be a little on the safe side to assume the problem is the same when number 11 shows up with exactly the same symptoms?