I just got through listening to the new 1969/12/31 release. Really nice sound, seems like an honest representation of the live sound. Interestingly it sounds to me like it's bridging the gap between the original Band of Gypsys album and the later live recordings, particularly Berkeley which was May 1970. Yet it's still unimstakeably that "BOG" sound.
And listening again to bill bokey's clip it sounds like this modded fuzz can come very close to the BOG fuzz sound. I really, really want to try it myself, but will have to wait until a used Dunlop Hendrix fuzz comes up for a decent price. The BOG fuzz has this beautiful low-mid grunt and "clank", but also has excellent sustain and a lot of saturation full up, and a very gradual amount of fuzz. Very unlike a stock fuzzface which is wooly when full up, and cleans up rather abruptly.
Anyone have some easy-to-follow instructions and/or photos showing how to mod a fuzzface for this setup?
Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
Moderators: VelvetGeorge, BUG
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shakti
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Re: Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
JTM45 RS OT, 1973 18W, JTM45/100, JTM50, JMP50 1986, JMP100 "West Coast", AC15, AC30, BF Super Reverb, Boogie Mk 1, Hiwatt CP103, DR103
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daveweyer
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Re: Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
Here is a paragraph from Technology Of The Fuzz:
"At one point in the past, Dunlop made FF clones. The JH1 and JH2 were both attempts to combine the Fuzz Face circuit with the purchased rights to Jimi's name (bought from the JH estate, as noted on the bottom of the pedal). Both were made with high gain silicon transistors and sounded dreadful (IMHO). The JH2 used the MPSA18, with a typical gain of 900! To my ear, these seem to have a "sticky" or "constricted" quality about them.
Later, Dunlop bought the FF trademarks and began manufacturing the FF as a reissue. Dunlop actually arranged for new manufactured "NKT275" germanium devices to be made for them, and is shipping these in its latest reissues. Reports are that these are OK sounding, much better than the ill-fated JH series.
The JH1 and JH2 are a great value for the DIY'er. You get that neato round case for cheap because they sound horrible. You can then rebuild the real FF circuit onto the circuit board in less than an hour, and have your own great sounding FF.
This all makes good sense - in any device that has so few parts, the qualities of the parts will show through.
I've also done some experimentation with germanium devices other than the AC128 and NKT275. I found a number of germanium types, measured their gains, and then listened to them. The results are pretty consistent - get the right gain and frequency response and the numbers printed on the cases don't matter. I like the 2N527 from GE (very consistent!) and the 2N508, also GE. The 508 is a little hotter, for more of a metal tone. Reports of results on the ECG158 are mixed. Some people are very happy with it, some not. I suspect that this can be put down to the variablility of the devices. Measure what you get!!"
**********************************
There are good schematics on the site, and West Coast mods are shown but not named as such.
You just have to be careful not to get too much beta or the FF will sound all scratchy.
BC108s had widely varied current gain, from 100 all the way to 800. I think most of us who modded FF units feel most comfortable in the range of 100-200, say a 2N525 in the first slot, and a 2N591 in the second.
The silicon NPN devices will work well too, but their gain is usually higher. The 2N3391A is in the 200 range. Bill likes a little more of a metal twinge, so more beta for that especially. The tones he got were remarkably close I thought, at least to that period. It makes sense too, because we had replaced all of Jimi's NKT275s and AC128s by then. I remember having a dish full of the old metal cased transistors sitting there at West Coast.
"At one point in the past, Dunlop made FF clones. The JH1 and JH2 were both attempts to combine the Fuzz Face circuit with the purchased rights to Jimi's name (bought from the JH estate, as noted on the bottom of the pedal). Both were made with high gain silicon transistors and sounded dreadful (IMHO). The JH2 used the MPSA18, with a typical gain of 900! To my ear, these seem to have a "sticky" or "constricted" quality about them.
Later, Dunlop bought the FF trademarks and began manufacturing the FF as a reissue. Dunlop actually arranged for new manufactured "NKT275" germanium devices to be made for them, and is shipping these in its latest reissues. Reports are that these are OK sounding, much better than the ill-fated JH series.
The JH1 and JH2 are a great value for the DIY'er. You get that neato round case for cheap because they sound horrible. You can then rebuild the real FF circuit onto the circuit board in less than an hour, and have your own great sounding FF.
This all makes good sense - in any device that has so few parts, the qualities of the parts will show through.
I've also done some experimentation with germanium devices other than the AC128 and NKT275. I found a number of germanium types, measured their gains, and then listened to them. The results are pretty consistent - get the right gain and frequency response and the numbers printed on the cases don't matter. I like the 2N527 from GE (very consistent!) and the 2N508, also GE. The 508 is a little hotter, for more of a metal tone. Reports of results on the ECG158 are mixed. Some people are very happy with it, some not. I suspect that this can be put down to the variablility of the devices. Measure what you get!!"
**********************************
There are good schematics on the site, and West Coast mods are shown but not named as such.
You just have to be careful not to get too much beta or the FF will sound all scratchy.
BC108s had widely varied current gain, from 100 all the way to 800. I think most of us who modded FF units feel most comfortable in the range of 100-200, say a 2N525 in the first slot, and a 2N591 in the second.
The silicon NPN devices will work well too, but their gain is usually higher. The 2N3391A is in the 200 range. Bill likes a little more of a metal twinge, so more beta for that especially. The tones he got were remarkably close I thought, at least to that period. It makes sense too, because we had replaced all of Jimi's NKT275s and AC128s by then. I remember having a dish full of the old metal cased transistors sitting there at West Coast.
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Xplorer
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Re: Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
it's easy to do. there are the indications from Bill, and i've posted a link for some picture of mine.shakti wrote:I just got through listening to the new 1969/12/31 release. Really nice sound, seems like an honest representation of the live sound. Interestingly it sounds to me like it's bridging the gap between the original Band of Gypsys album and the later live recordings, particularly Berkeley which was May 1970. Yet it's still unimstakeably that "BOG" sound.
And listening again to bill bokey's clip it sounds like this modded fuzz can come very close to the BOG fuzz sound. I really, really want to try it myself, but will have to wait until a used Dunlop Hendrix fuzz comes up for a decent price. The BOG fuzz has this beautiful low-mid grunt and "clank", but also has excellent sustain and a lot of saturation full up, and a very gradual amount of fuzz. Very unlike a stock fuzzface which is wooly when full up, and cleans up rather abruptly.
Anyone have some easy-to-follow instructions and/or photos showing how to mod a fuzzface for this setup?
a 1k5, a 6k8, VR1 and VR2 down to zero, a 10 000 mustard pf, removing C5 Under the board, a 100k instead of the 82k, and a 15k at the signal input.
it's Worth it ! totaly.
i don't know how it sounds when used with another amp and tubes, but it's perfect for the west coast amp and the bog tone.
i think that it opens doors for some other tests, using other transistors, etc but overall, it's self sufficient, it's a working one ...
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daveweyer
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Re: Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
Still looking at the 3 transistor West Coast fuzz, I haven't forgotten.
Hope Bill will honor us with some more sounds in the meantime.
Hope Bill will honor us with some more sounds in the meantime.
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Tone seaker
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Re: Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
one thing to remember about 1970 tone. BOG was tuned down the rest of 70 was not. i have often wondered why he stoped tunning down in 1970 
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daveweyer
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Re: Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
For those of you who read my missive on Jimi's Wah pedal, you may have had the same questions that repeatedly pop up in my correspondence about it:
Did Jimi sign the pedal or not?
and,
Did he use the pedal at Woodstock or not?
My answer to both questions is yes, he did and he did. But that doesn't mean there are not skeptics who doubt the script on the inside of the pedal is his. It's just that I don't have time to argue about it and continually defend my work and relationship to Jimi, therefore I just let the believers and skeptics argue about it.
As for Woodstock, since we had repaired and modded all his gear just prior to the occasion, there was never any question in my mind that he used all the stuff we had just finished for him. After the concert I asked him how all of the modded gear performed and he said, (I think this is a pretty accurate quote too) "Groovy man really groovy, I love what you're doing for us, and I'm going to keep the pedal until you make me an even better one!"
One of our guys who made it to Woodstock and saw Jimi play close up, reported that he saw the West Coast sticker on the bottom of the pedal when they were setting up. I'd have him testify but he's gone now too.
The pedal has been examined closely by the forensic Jimi experts (like you guys too) and they believe it is the same pedal. Even the film was enhanced digitally to reveal hidden details on the pedal casing. That said, there are those who don't or can't believe it could be the same one, and again, I can't be in the middle of that argument.
So I have left the questions open for the world to sort out. That's why I wrote the article with the words I did. I'm sure my own thoughts and recollections are accurate, but I'm just a guy who worked for Jimi.
Did Jimi sign the pedal or not?
and,
Did he use the pedal at Woodstock or not?
My answer to both questions is yes, he did and he did. But that doesn't mean there are not skeptics who doubt the script on the inside of the pedal is his. It's just that I don't have time to argue about it and continually defend my work and relationship to Jimi, therefore I just let the believers and skeptics argue about it.
As for Woodstock, since we had repaired and modded all his gear just prior to the occasion, there was never any question in my mind that he used all the stuff we had just finished for him. After the concert I asked him how all of the modded gear performed and he said, (I think this is a pretty accurate quote too) "Groovy man really groovy, I love what you're doing for us, and I'm going to keep the pedal until you make me an even better one!"
One of our guys who made it to Woodstock and saw Jimi play close up, reported that he saw the West Coast sticker on the bottom of the pedal when they were setting up. I'd have him testify but he's gone now too.
The pedal has been examined closely by the forensic Jimi experts (like you guys too) and they believe it is the same pedal. Even the film was enhanced digitally to reveal hidden details on the pedal casing. That said, there are those who don't or can't believe it could be the same one, and again, I can't be in the middle of that argument.
So I have left the questions open for the world to sort out. That's why I wrote the article with the words I did. I'm sure my own thoughts and recollections are accurate, but I'm just a guy who worked for Jimi.
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daveweyer
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Re: Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
Just a quick update:
As might be expected, the sale of Jimi's gear has brought out a number of interested parties, either to bid on the equipment or to comment on it one way or another. There are some doubters of course, and even Roger Mayer weighed in with a denial of having done the reamp/slave mod on the Guild amp. His words were careful and measured so as not to take too strong of a position on the authenticity of the equipment, but he had obviously heard of the sale, and read the descriptions of the gear.
My point here is that West Coast Organ and Amp is not going to go away or be erased from history because some people find it inconvenient. We were there, worked on, and built gear for Jimi, end of story. Maybe some folks didn't notice West Coast stickers all over the gear, or notice that circuits had been changed, or that Jimi's sound changed, or that new necks and/or bodies were replaced on his guitars, or that fret jobs had been done, or that notches had been cut in the 12th fret on some of his Strats, or that his amps were loaded with 6550s, or a dozen other things. They SHOULD have noticed if they were that close to Jimi, and maybe that is why they prefer to ignore or diminish West Coast Organ and Amp as inconsequential; after all it sort of makes them look incompetent.
The gear is real and it will become part of the Jimi history as it rightfully should. My humble suggestion is that keepers of Jimi stories which do not include West Coast Organ and Amp make room for another chapter, and coordinate their stories to fit our story in a much more complete and encompassing narrative. The stories HAVE to be complementary after all because the actions of Hendrix regarding West Coast actually happened, took time out of his life, caused invoices to be generated, mileage to be used up, words and ideas to be exchanged, phone calls to be made, reports to be generated, amps to work longer and harder, and fans to be pleased with better and better sound among many other things.
Many of you here have proved the stories correct with your faithful builds of West Coast mods. Except for room acoustics and mics/placement, you HAVE BOG sound. Say what you will, it is pretty clear to rational and reasonable minds including some rock and roll hall-of-famers that I have shown the clips to. Lacking pictures of Jimi and me leaning on the back wall of West Coast smoking reefer together, the sound will have to bear the burden of proof.
I'll provide details of the sale when and if the gear finds a good historical home. This may take some time, the buyers in this range are few and far between.
As might be expected, the sale of Jimi's gear has brought out a number of interested parties, either to bid on the equipment or to comment on it one way or another. There are some doubters of course, and even Roger Mayer weighed in with a denial of having done the reamp/slave mod on the Guild amp. His words were careful and measured so as not to take too strong of a position on the authenticity of the equipment, but he had obviously heard of the sale, and read the descriptions of the gear.
My point here is that West Coast Organ and Amp is not going to go away or be erased from history because some people find it inconvenient. We were there, worked on, and built gear for Jimi, end of story. Maybe some folks didn't notice West Coast stickers all over the gear, or notice that circuits had been changed, or that Jimi's sound changed, or that new necks and/or bodies were replaced on his guitars, or that fret jobs had been done, or that notches had been cut in the 12th fret on some of his Strats, or that his amps were loaded with 6550s, or a dozen other things. They SHOULD have noticed if they were that close to Jimi, and maybe that is why they prefer to ignore or diminish West Coast Organ and Amp as inconsequential; after all it sort of makes them look incompetent.
The gear is real and it will become part of the Jimi history as it rightfully should. My humble suggestion is that keepers of Jimi stories which do not include West Coast Organ and Amp make room for another chapter, and coordinate their stories to fit our story in a much more complete and encompassing narrative. The stories HAVE to be complementary after all because the actions of Hendrix regarding West Coast actually happened, took time out of his life, caused invoices to be generated, mileage to be used up, words and ideas to be exchanged, phone calls to be made, reports to be generated, amps to work longer and harder, and fans to be pleased with better and better sound among many other things.
Many of you here have proved the stories correct with your faithful builds of West Coast mods. Except for room acoustics and mics/placement, you HAVE BOG sound. Say what you will, it is pretty clear to rational and reasonable minds including some rock and roll hall-of-famers that I have shown the clips to. Lacking pictures of Jimi and me leaning on the back wall of West Coast smoking reefer together, the sound will have to bear the burden of proof.
I'll provide details of the sale when and if the gear finds a good historical home. This may take some time, the buyers in this range are few and far between.
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niknik
- Senior Member
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Re: Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
Hello everybody,
my first post on this forum. here is Nicola from Italy, so please excuse me if my english is not good..
I read all the posts and topics here, and I have to thanks everybody for what now I know about amps and circuits. I am just at the beginning of my electronic travel, but I am a good student..
I'm here to give my little contribution, if I can..
Daveweyer thanks so much for all you've shared, it is a pleasure and an honor for me to read your post and I'm trying to experiment all you write, literally!
Also Xplorer, bill bokey, and you all, thanks again
I have a thousand questions, and I hope you could help me little by little
my last two buildings are: a super lead west coast spec with a nos Stancor A-8053 and a Mercury M3-67P with 6550 and some nos components, and a stock 45/100 with Marstran ot and pt with kt66
Xplorer, is your 45/100 stock? is it running at circa 560v or lower? 2k2 on screen? filtering?
my 45/100 is a very good amp but completely stock like it is, has some little ghosts at high volume, especially with a fuzz, I know it is usual with low filtering, but what is best way to solve this issue whitout changing to much the feeling? separate supplies for the screens? Marstran pt has also lower ht secondary windings
thanks again
hope talk to you soon
ciao!!
Nicola
my first post on this forum. here is Nicola from Italy, so please excuse me if my english is not good..
I read all the posts and topics here, and I have to thanks everybody for what now I know about amps and circuits. I am just at the beginning of my electronic travel, but I am a good student..
I'm here to give my little contribution, if I can..
Daveweyer thanks so much for all you've shared, it is a pleasure and an honor for me to read your post and I'm trying to experiment all you write, literally!
Also Xplorer, bill bokey, and you all, thanks again
I have a thousand questions, and I hope you could help me little by little
my last two buildings are: a super lead west coast spec with a nos Stancor A-8053 and a Mercury M3-67P with 6550 and some nos components, and a stock 45/100 with Marstran ot and pt with kt66
Xplorer, is your 45/100 stock? is it running at circa 560v or lower? 2k2 on screen? filtering?
my 45/100 is a very good amp but completely stock like it is, has some little ghosts at high volume, especially with a fuzz, I know it is usual with low filtering, but what is best way to solve this issue whitout changing to much the feeling? separate supplies for the screens? Marstran pt has also lower ht secondary windings
thanks again
hope talk to you soon
ciao!!
Nicola
Sammy who?!
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Mr.Glenny
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Re: Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
Goodmorning everyone!!! My name is Glen and I write from Italy ... I follow passionately! This forum is really cool !!! excuse me but I take this opportunity because I would like to contact niknik ...niknik wrote:Hello everybody,
my first post on this forum. here is Nicola from Italy, so please excuse me if my english is not good..
I read all the posts and topics here, and I have to thanks everybody for what now I know about amps and circuits. I am just at the beginning of my electronic travel, but I am a good student..
I'm here to give my little contribution, if I can..
Daveweyer thanks so much for all you've shared, it is a pleasure and an honor for me to read your post and I'm trying to experiment all you write, literally!
Also Xplorer, bill bokey, and you all, thanks again
I have a thousand questions, and I hope you could help me little by little
my last two buildings are: a super lead west coast spec with a nos Stancor A-8053 and a Mercury M3-67P with 6550 and some nos components, and a stock 45/100 with Marstran ot and pt with kt66
Xplorer, is your 45/100 stock? is it running at circa 560v or lower? 2k2 on screen? filtering?
my 45/100 is a very good amp but completely stock like it is, has some little ghosts at high volume, especially with a fuzz, I know it is usual with low filtering, but what is best way to solve this issue whitout changing to much the feeling? separate supplies for the screens? Marstran pt has also lower ht secondary windings
thanks again
hope talk to you soon
ciao!!
Nicola
"ciao Nicola mi piacerebbe fare due chiacchiere...se sei d'accordo ecco la mia mail: 69heyjoe@libero.it
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Xplorer
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Re: Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
hi, thanks. Well i didn't mod my 45/100 .... i modded a metro SL69 according to Dave's mod. it has 530 volts on the plates, not 560 volts.niknik wrote:Hello everybody,
my first post on this forum. here is Nicola from Italy, so please excuse me if my english is not good..
I read all the posts and topics here, and I have to thanks everybody for what now I know about amps and circuits. I am just at the beginning of my electronic travel, but I am a good student..
I'm here to give my little contribution, if I can..
Daveweyer thanks so much for all you've shared, it is a pleasure and an honor for me to read your post and I'm trying to experiment all you write, literally!
Also Xplorer, bill bokey, and you all, thanks again
I have a thousand questions, and I hope you could help me little by little
my last two buildings are: a super lead west coast spec with a nos Stancor A-8053 and a Mercury M3-67P with 6550 and some nos components, and a stock 45/100 with Marstran ot and pt with kt66
Xplorer, is your 45/100 stock? is it running at circa 560v or lower? 2k2 on screen? filtering?
my 45/100 is a very good amp but completely stock like it is, has some little ghosts at high volume, especially with a fuzz, I know it is usual with low filtering, but what is best way to solve this issue whitout changing to much the feeling? separate supplies for the screens? Marstran pt has also lower ht secondary windings
thanks again
hope talk to you soon
ciao!!
Nicola
i'll re do a Superlead build, this time with a marstran 45/100 PT with 560 volts.
yes, 2k2.
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niknik
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Re: Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
My 45/100 has stock specs too, except for 2k2 screen resistors, B+ is around 560v with bias 25ma.
all nos mustard caps, a mix of allen bradley and phier resistors, and some nos 12ax7 preamp tubes (mullard in v1 and telefunken in v3)
Power tubes are new gold lion kt66s
choke is a 3H from metroamp store
this amp is solid and tight, maybe a little too much, also with low filtering, but after all is a good amp when I play clean or semi crunch.
With volume at 1 or 2 o'clock and a stratocaster is ok (I play a lot with guitar volume, from 3 to 10) but when I engage a germanium fuzz face with full volume and fuzz at 0 or 1, I feel something wrong, distortion is not so good, short sustain and too much ghosts.
I'm trying to fix this issue, maybe I have to lower the screen voltage, I don't know..
Is better to change the choke with a 20H radiospare, or to utilize separate screen connections from lower ht secondary tap, like Dave mentioned?
I prefer not to raise filter caps value, to avoid stiffness, if possible.
thanx
all nos mustard caps, a mix of allen bradley and phier resistors, and some nos 12ax7 preamp tubes (mullard in v1 and telefunken in v3)
Power tubes are new gold lion kt66s
choke is a 3H from metroamp store
this amp is solid and tight, maybe a little too much, also with low filtering, but after all is a good amp when I play clean or semi crunch.
With volume at 1 or 2 o'clock and a stratocaster is ok (I play a lot with guitar volume, from 3 to 10) but when I engage a germanium fuzz face with full volume and fuzz at 0 or 1, I feel something wrong, distortion is not so good, short sustain and too much ghosts.
I'm trying to fix this issue, maybe I have to lower the screen voltage, I don't know..
Is better to change the choke with a 20H radiospare, or to utilize separate screen connections from lower ht secondary tap, like Dave mentioned?
I prefer not to raise filter caps value, to avoid stiffness, if possible.
thanx
Sammy who?!
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Roe
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Re: Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
I have a 45/100 that is fairly close to the west coast specs while staying very close to the original formula. Plate voltage at idle is 535v, with kt66s, 1k screen resistors in series with a RS choke with 690 ohms DC resistance. At full power, the screens sag to 400v and the plates to 500v. This setup has worked well for me and the new Russian Genalex kt66s sound fine in this application
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Super 100 amps: 1202-119 & 1202-84
JTM45 RS OT JTM50 JMP50 1959/2203/34/39
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Super 100 amps: 1202-119 & 1202-84
JTM45 RS OT JTM50 JMP50 1959/2203/34/39
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niknik
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Re: Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
Thanks Roe,
I will change the choke, I have got a spare RS 20H 690ohm somewhere.
I'll post the results
I will change the choke, I have got a spare RS 20H 690ohm somewhere.
I'll post the results
Sammy who?!
-
niknik
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Re: Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
Ok, I changed the choke in my 45/100, now with the RS choke, B+ is at 553v, and screen current is at 541v, with amp volume at zero.
with all the controls at full and with a strato strumming some chords, the plate sags to 495v and the screen sags to 403v, like Roe said.
The amp now is better, less ghosts than before,
but with fuzz engaged, ghosts are still too much presents for my taste..
I left 2k2 resistors in place for now, but I think I will try the separate supply for the screens from lower HT secondary tap, If I figure out how..
I suppose another full wave rectifier rail from low HT secondary, than straight to choke and to a filter cap (or maybe the contrary, I don't know), and than straight to screens with no res in pins 4.
Also modifying main rail supply, going from mains to PI through a 100ohm resistor..
is it quite correct?
when the amp will be ok, I'll do some clips
with all the controls at full and with a strato strumming some chords, the plate sags to 495v and the screen sags to 403v, like Roe said.
The amp now is better, less ghosts than before,
but with fuzz engaged, ghosts are still too much presents for my taste..
I left 2k2 resistors in place for now, but I think I will try the separate supply for the screens from lower HT secondary tap, If I figure out how..
I suppose another full wave rectifier rail from low HT secondary, than straight to choke and to a filter cap (or maybe the contrary, I don't know), and than straight to screens with no res in pins 4.
Also modifying main rail supply, going from mains to PI through a 100ohm resistor..
is it quite correct?
when the amp will be ok, I'll do some clips
Sammy who?!
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Xplorer
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Re: Jimi Hendrix' Gear and Mods at West Coast Organ and Amp
yes, please do some clips ! 