Authentic JTM 45/100 build diary. Clips added.
Posted: Sun Jun 06, 2010 8:42 am
Dear forum members,
i received my metro package recently and i've also hunted down almost all of the NOS parts for the build (the hunt was obsessive, with highs and lows and lasted 3-4 months). I thought i'd go over my stuff to see if i haven't forgotten something, so i put the parts on the boards to see if everything's there. I didn't want to miss the opportunity to show off and share some close-up vintage-parts-porn with you here. So this is sort of "Part I" of the build - still looking for some parts and checking if everything else is there.
As you see i still don't have 2x 8uF or 10uF @ 150v Hunts electrolytics and the 250uF Wima has one very short lead that has to be extended (so i hope to find one with better leads). Also the Erie 32+32uF is not "vintage correct" and from a tad later era - maybe i will find a good substitute for this one too. The 68k's are the only ones i couldn't find NOS - so these are used and looks like they've been pulled of a JTM-45 - for what ever reason ( i still don't know if they are any good though). And of course i'm short of 7x 32uF arced RS logo electrolytics @ 450v. Maybe i'll hunt these and add one by one during the next year(s) when the amp is built.
Almost everything else is there. BrianH's boards are fantastic, but i still hope to get some original RS turret board material somewhere for this build, as almost every single part is era correct (including even date codes for the most part). So please let me know if you have some of it or know where i might get some. (as i've stated earlier - i have loads of nos Marshall parts to trade for the RS boards - lot's of them can be seen here and there is more - i'll make pics of the rest sometime next week). Almost anything can be added later on, but it's, of course, different with the turret board itself - so this is what keeps me back from starting the build right away.
Ah, and the last thing i'm still hoping to find are the era correct, black, not brown, colored impedance and voltage selectors - that would be the only parts really indicating a non-vintage 45/100. I think i even got the switches right, including the ring, that looks pretty much spot on to me.
I haven't decided yet if i want to go with Dickinson specs or not and i'm open to suggestions either way. I have all the needed parts for that and i think, if i dig deep in my parts box, i should find also EXACTLY the same differing parts - the iskras, except 470r and 100k, i have the 500pF RS mica (though the leads are crappy short), etc.
I also haven't decided which parts to choose at the positions where i have put some parts close to the board - should i go with the corresponding pihers instead of carbon comps? If i go with carbon comps, shall i choose the standard ones or the mil spec ones (i suppose they mught have slightly different characteristics?)? Also i've heard that the wimas actually sound crappy - so maybe go with the BC cap instead. And when we're taling BC caps - maybe better changing them alltogether to Rifa?
I'm very interested in your opinions and suggestions guys, so please let me know if you have anything to say about these questions.
I haven't ordered the KT66's yet, but as NOS is out of question because of $ right now, i think i will order TAD KT66's - i've read here on the forum, mostly in Re's posts, that these are the best from the chinese and russian ones - even better than Valve Art, which actually makes these, but afaik they are selected and tested to better tolerances or something.
Ok, cut to the chase, here are the pics:
And here's a link to the whole album with more and higher res pics:
http://s802.photobucket.com/albums/yy30 ... S%20Parts/" onclick="window.open(this.href);return false;
Kind regards,
VintageCharlie
i received my metro package recently and i've also hunted down almost all of the NOS parts for the build (the hunt was obsessive, with highs and lows and lasted 3-4 months). I thought i'd go over my stuff to see if i haven't forgotten something, so i put the parts on the boards to see if everything's there. I didn't want to miss the opportunity to show off and share some close-up vintage-parts-porn with you here. So this is sort of "Part I" of the build - still looking for some parts and checking if everything else is there.
As you see i still don't have 2x 8uF or 10uF @ 150v Hunts electrolytics and the 250uF Wima has one very short lead that has to be extended (so i hope to find one with better leads). Also the Erie 32+32uF is not "vintage correct" and from a tad later era - maybe i will find a good substitute for this one too. The 68k's are the only ones i couldn't find NOS - so these are used and looks like they've been pulled of a JTM-45 - for what ever reason ( i still don't know if they are any good though). And of course i'm short of 7x 32uF arced RS logo electrolytics @ 450v. Maybe i'll hunt these and add one by one during the next year(s) when the amp is built.
Almost everything else is there. BrianH's boards are fantastic, but i still hope to get some original RS turret board material somewhere for this build, as almost every single part is era correct (including even date codes for the most part). So please let me know if you have some of it or know where i might get some. (as i've stated earlier - i have loads of nos Marshall parts to trade for the RS boards - lot's of them can be seen here and there is more - i'll make pics of the rest sometime next week). Almost anything can be added later on, but it's, of course, different with the turret board itself - so this is what keeps me back from starting the build right away.
Ah, and the last thing i'm still hoping to find are the era correct, black, not brown, colored impedance and voltage selectors - that would be the only parts really indicating a non-vintage 45/100. I think i even got the switches right, including the ring, that looks pretty much spot on to me.
I haven't decided yet if i want to go with Dickinson specs or not and i'm open to suggestions either way. I have all the needed parts for that and i think, if i dig deep in my parts box, i should find also EXACTLY the same differing parts - the iskras, except 470r and 100k, i have the 500pF RS mica (though the leads are crappy short), etc.
I also haven't decided which parts to choose at the positions where i have put some parts close to the board - should i go with the corresponding pihers instead of carbon comps? If i go with carbon comps, shall i choose the standard ones or the mil spec ones (i suppose they mught have slightly different characteristics?)? Also i've heard that the wimas actually sound crappy - so maybe go with the BC cap instead. And when we're taling BC caps - maybe better changing them alltogether to Rifa?
I'm very interested in your opinions and suggestions guys, so please let me know if you have anything to say about these questions.
I haven't ordered the KT66's yet, but as NOS is out of question because of $ right now, i think i will order TAD KT66's - i've read here on the forum, mostly in Re's posts, that these are the best from the chinese and russian ones - even better than Valve Art, which actually makes these, but afaik they are selected and tested to better tolerances or something.
Ok, cut to the chase, here are the pics:
And here's a link to the whole album with more and higher res pics:
http://s802.photobucket.com/albums/yy30 ... S%20Parts/" onclick="window.open(this.href);return false;
Kind regards,
VintageCharlie