I have a question for you Marshall Guys... I am building a 1987 plexi 50 watter using EL34's. What are the transformers to use? I'm not really going for originality but I am not sure which ones to chose? What is the difference between the JCM800, JCM900 and the JTM45 trannies? I know the JTM45 power transformer will have tap for the rectifier. I am Fender guy for the most part and I really don't know all of the Marshall details. Is this the vertical mount verses the horizontal mount? Or is one set bigger then the other? If I am not mistaken is the JTM45 OT smaller then the JCM800/900 OT's? Last question what is the best Marshall book to buy to learn and digest this info? Thanks for all of the help.
Thanks,
Steve
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Marshall Transformers??
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Plexi
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I'll probaly answer these in reverse.. The best marshall refrence book,is the Doyle book. Just don't use the 18watt schematic..lol
But realy it is packed with info.
As for the transformers.. Everyone has there own view of "best" one.
If your building plexi.. there are many.. And prices vary..
OEI OT is wonderfull, and some like the Mercury Magnets..
Heyboer has the PT and OT too.
New Sensor also sells the PT and OT.
I've built some with the OEI OT, and Heyboer PT, Great price and amp turned out very good. the PT had a tube recto,and could switch from SS to tube for an option. And it didn't cost that much. those Heyboer guys are just great, you tell them what you want, and they give you options,and usually better than what you ask for..lol
Don't go with any of the new 900 stuff..
Weber sells a chassis. And has links to transformers.
I also think Hoffman amps,has tons of good info and links.
Richie
But realy it is packed with info.
As for the transformers.. Everyone has there own view of "best" one.
If your building plexi.. there are many.. And prices vary..
OEI OT is wonderfull, and some like the Mercury Magnets..
Heyboer has the PT and OT too.
New Sensor also sells the PT and OT.
I've built some with the OEI OT, and Heyboer PT, Great price and amp turned out very good. the PT had a tube recto,and could switch from SS to tube for an option. And it didn't cost that much. those Heyboer guys are just great, you tell them what you want, and they give you options,and usually better than what you ask for..lol
Don't go with any of the new 900 stuff..
Weber sells a chassis. And has links to transformers.
I also think Hoffman amps,has tons of good info and links.
Richie
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jaysg
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I replaced the Drake in a JCM800 2204 with the 50W OEI plexi OT. I hesitate to call the difference extreme, but it is at some level. The Drake results in a generally treblier tone regardless of knob settings. If you want the 80's sound, the OEI probably won't get you there. The midrange is different. With the OEI, I had to increase the presence. The rest of the setting changes were subtle, iirc.
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Plexi
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Oh, there are many links to sites that show the insides of plexi amps. It helps sometimes to see the layouts..
Joe has some good info mapped out on them..
http://www.obsoleteelectronics.com/Mars ... l_tech.htm
And a link to some inside shots
http://home.socal.rr.com/fiftywatt/
Richie
Joe has some good info mapped out on them..
http://www.obsoleteelectronics.com/Mars ... l_tech.htm
And a link to some inside shots
http://home.socal.rr.com/fiftywatt/
Richie
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EBE
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myamp
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This link is a little off the subject it is a JTM45 but the pictures are good
http://www.cathedralstone.net/Pages/JTM45.htm
http://www.cathedralstone.net/Pages/JTM45.htm
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Plexi
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Norm: """Have you tried the deluxe reverb transformer from new sensor?"""
Yes i've used them.But its been a long time ago. Bruce Collins brought up not to long ago,he was using them for his 5E3 kits. And then NS changed something on them,or who they had making them. And that they went downhill. But they were supposed to change them back to the way they were. I know Bruce stocks all the trannys for his kits,and you can get them from him.
I don't know if he still uses the NS or they did in fact change back. but he would know.
I do know,i've used there PTs and sure didn't like those, all the ones i had ran very hot.
I've been useing heyboer for all the fender stuff now days,and never had a problem. All very well built,and they send them very quick.
I've even had to get oddball fender OTs. And just tell them the number,and they build one like it,or better. I'm sure they would also have one.
Richie
Richie
Yes i've used them.But its been a long time ago. Bruce Collins brought up not to long ago,he was using them for his 5E3 kits. And then NS changed something on them,or who they had making them. And that they went downhill. But they were supposed to change them back to the way they were. I know Bruce stocks all the trannys for his kits,and you can get them from him.
I don't know if he still uses the NS or they did in fact change back. but he would know.
I do know,i've used there PTs and sure didn't like those, all the ones i had ran very hot.
I've been useing heyboer for all the fender stuff now days,and never had a problem. All very well built,and they send them very quick.
I've even had to get oddball fender OTs. And just tell them the number,and they build one like it,or better. I'm sure they would also have one.
Richie
Richie
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bnwitt
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New Sensor
Plexi,
I have used plenty of the Deluxe reverb trannies from New Sensor and what happened in the last year is they took on a second line of fender style trannies made in Taiwan for a cheaper alternative. They also (simultaneously) ran out of the american made units and shipped some of the foreign units to fill orders. Bruce wasn't happy with the foreign model's impedance and returned them. I had the same reaction and have returned 5 of them and am waiting on replacement american units which are fine. I have only used their 25 watt Deluxe, and 50 watt fender style PT's but I haven't had any run hot issues with them. I have a 100 watt fender style PT I am about to use for a Big Box twin though. Any particular model you had heat issues with?
I have used plenty of the Deluxe reverb trannies from New Sensor and what happened in the last year is they took on a second line of fender style trannies made in Taiwan for a cheaper alternative. They also (simultaneously) ran out of the american made units and shipped some of the foreign units to fill orders. Bruce wasn't happy with the foreign model's impedance and returned them. I had the same reaction and have returned 5 of them and am waiting on replacement american units which are fine. I have only used their 25 watt Deluxe, and 50 watt fender style PT's but I haven't had any run hot issues with them. I have a 100 watt fender style PT I am about to use for a Big Box twin though. Any particular model you had heat issues with?
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jaysg
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I know this is getting farther off topic, but have any of you had much experience with Dave Allen's OTs? I'm looking for a sonic improvement with a 2x6L6 Fender that isn't broken. The prices seem fair to me - $60 to $70 for a retail customer depending on the model. I did a head to head comparison with an old BF Showman and I could hear some sour harmonics in mine that weren't in the Showman. The circuits were close enough. fwiw, the sour harmonics were also in a non-UL MV SFTR that we tried.
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EBE
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Re: New Sensor
Great, this isn't what I a had hoped to hear. I have a NSC041318 (made in tawain) that I picked up off of ebay that I planned on either an 18watt build or maybe a homebrew deluxe reverb.bnwitt wrote:Plexi,
I have used plenty of the Deluxe reverb trannies from New Sensor and what happened in the last year is they took on a second line of fender style trannies made in Taiwan for a cheaper alternative. They also (simultaneously) ran out of the american made units and shipped some of the foreign units to fill orders. Bruce wasn't happy with the foreign model's impedance and returned them. I had the same reaction and have returned 5 of them and am waiting on replacement american units which are fine. I have only used their 25 watt Deluxe, and 50 watt fender style PT's but I haven't had any run hot issues with them. I have a 100 watt fender style PT I am about to use for a Big Box twin though. Any particular model you had heat issues with?
Norm
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Wannatone
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Some Marshall related links:
http://www.drtube.com/marshall.htm
http://marstran.8k.com/Transformer%20Codes.htm
http://marstran.8k.com/Historic%20Data%20Base.htm
http://members.shaw.ca/house-of-jim/
http://www.lastwordsmusic.com/clay/mars ... s_101.html
Trannies:
http://www.mercurymagnetics.com/axiompricing.htm
Btw, you can build your own output tranny:
http://europa.spaceports.com/~fishbake/ot1/ot.htm
Just get a high quality iron. You won´t have fun with cheapo stuff. BUT, you might do even better to start with the most crappy tranny to learn by doing.
Adrian
http://www.drtube.com/marshall.htm
http://marstran.8k.com/Transformer%20Codes.htm
http://marstran.8k.com/Historic%20Data%20Base.htm
http://members.shaw.ca/house-of-jim/
http://www.lastwordsmusic.com/clay/mars ... s_101.html
Trannies:
http://www.mercurymagnetics.com/axiompricing.htm
Btw, you can build your own output tranny:
http://europa.spaceports.com/~fishbake/ot1/ot.htm
Just get a high quality iron. You won´t have fun with cheapo stuff. BUT, you might do even better to start with the most crappy tranny to learn by doing.
Adrian
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