Had this awesome block end 45 in the shop and was able to make a clip comparing it to a GPM 45 with GECs and mustards. I think it fared very well, at times I couldn't tell a difference at all.
This was a real pleasure to work on and document.
george
[youtube]http://www.youtube.com/watch?v=SqLQfJ2URG0[/youtube]
'66 JTM 45 block end vs GPM 45040
Moderator: VelvetGeorge
-
VelvetGeorge
- Site Owner
- Posts: 7233
- Joined: Tue Oct 14, 2003 5:12 pm
- Just the numbers in order: 13492
- Location: The Murder Mitten
- Contact:
-
bill bokey
- Senior Member
- Posts: 490
- Joined: Sun Jan 02, 2011 2:54 pm
- Just the numbers in order: 13492
- Location: France
- Contact:
-
neikeel
- Senior Member
- Posts: 7231
- Joined: Tue Dec 06, 2005 8:31 am
- Location: Suffolk, England
Re: '66 JTM 45 block end vs GPM 45040
Yup the replica does nail it. 
BTW apart from mustards what resistors did you use?
BTW apart from mustards what resistors did you use?
Neil
-
VelvetGeorge
- Site Owner
- Posts: 7233
- Joined: Tue Oct 14, 2003 5:12 pm
- Just the numbers in order: 13492
- Location: The Murder Mitten
- Contact:
Re: '66 JTM 45 block end vs GPM 45040
Mostly NOS Allen Bradley CC.
george
george
- Attachments
-
- 1803 inside.jpg
- (172.87 KiB) Downloaded 1714 times
-
- 45040 inside.jpg
- (163.19 KiB) Downloaded 1714 times
-
VelvetGeorge
- Site Owner
- Posts: 7233
- Joined: Tue Oct 14, 2003 5:12 pm
- Just the numbers in order: 13492
- Location: The Murder Mitten
- Contact:
Re: '66 JTM 45 block end vs GPM 45040
These are the pics you see inset on the video.
george
george
- Attachments
-
- GPM 45040.jpg
- (152.09 KiB) Downloaded 1713 times
-
- JTM 45 1803 small.jpg
- (212.92 KiB) Downloaded 1713 times
-
neikeel
- Senior Member
- Posts: 7231
- Joined: Tue Dec 06, 2005 8:31 am
- Location: Suffolk, England
Re: '66 JTM 45 block end vs GPM 45040
Ok so I see you replaced th etone stack cap on the original. It only has one screen dropper and there is another resistor on the filter cap (bleeder?/).VelvetGeorge wrote:Mostly NOS Allen Bradley CC.
george
On yours you have a PPIMV (Metro type 2, as opposed to LarMar) and, by the look of it a 0.68uF cap on the presence?
Neil
-
VelvetGeorge
- Site Owner
- Posts: 7233
- Joined: Tue Oct 14, 2003 5:12 pm
- Just the numbers in order: 13492
- Location: The Murder Mitten
- Contact:
Re: '66 JTM 45 block end vs GPM 45040
Yes, that tone stack cap is temporary, until he gets an era correct part.
Single 1k feeding the output screens.
Do you mean the .047uf box cap going to the main filter cap? That's the HT cap, goes to pin 2 of the rectifier tube.
The replica does have the PPIMV. The caps there and on the presence are .1uf, they are the rectangular type.
george
Single 1k feeding the output screens.
Do you mean the .047uf box cap going to the main filter cap? That's the HT cap, goes to pin 2 of the rectifier tube.
The replica does have the PPIMV. The caps there and on the presence are .1uf, they are the rectangular type.
george
-
neikeel
- Senior Member
- Posts: 7231
- Joined: Tue Dec 06, 2005 8:31 am
- Location: Suffolk, England
Re: '66 JTM 45 block end vs GPM 45040
Ah yes a box shaped cap! My old ones are the red tubular Hunts ones.VelvetGeorge wrote:Yes, that tone stack cap is temporary, until he gets an era correct part.
Single 1k feeding the output screens.
Do you mean the .047uf box cap going to the main filter cap? That's the HT cap, goes to pin 2 of the rectifier tube.
The replica does have the PPIMV. The caps there and on the presence are .1uf, they are the rectangular type.
george
Neil
-
Big Mike
- Senior Member
- Posts: 796
- Joined: Tue Oct 31, 2006 12:42 am
- Just the numbers in order: 7
- Location: East Bay California - Raider Nation
Re: '66 JTM 45 block end vs GPM 45040
Great job G! Sounds so good I don't think I could tell the difference.
Interesting way of laying out the PPIMV with the PI caps there. VEry cool.
I'd try it...but I switch my presence and master around LOL
Awesome work.
Interesting way of laying out the PPIMV with the PI caps there. VEry cool.
I'd try it...but I switch my presence and master around LOL
Awesome work.
Metroamp kit JMP50 - CM OT
Metroamp JTM45 turned JMP50 w/Classictone OT
Marshall 2550 Jubilee
Powered by Thorn and Kauer guitars
Scumback Speakers
Metroamp JTM45 turned JMP50 w/Classictone OT
Marshall 2550 Jubilee
Powered by Thorn and Kauer guitars
Scumback Speakers
-
VelvetGeorge
- Site Owner
- Posts: 7233
- Joined: Tue Oct 14, 2003 5:12 pm
- Just the numbers in order: 13492
- Location: The Murder Mitten
- Contact:
Re: '66 JTM 45 block end vs GPM 45040
This can only mean one thing......
you just knew this would happen.
george
you just knew this would happen.
george
- Attachments
-
- 1966 JTM 45 block end - front qtr view 600p.jpg
- (93.04 KiB) Downloaded 1611 times
-
- JTM 45 block end full amp rear qtr 600p.jpg
- (95.39 KiB) Downloaded 1611 times
-
MacGaden
- Wiki Editor
- Posts: 2189
- Joined: Wed Apr 20, 2005 5:57 am
- Just the numbers in order: 7
- Location: Fredericia, Denmark
Re: '66 JTM 45 block end vs GPM 45040
Very cool video, George. And block ends are just cool... Dare we ask for a block end JTM50 ? Neil has a cool one you can clone....
MacG.
"Play it right, Dad ! No More Dwiddely Dwiddely !
My son Adam at 3 years old. Best advice I ever got..
"Play it right, Dad ! No More Dwiddely Dwiddely !
My son Adam at 3 years old. Best advice I ever got..
-
neikeel
- Senior Member
- Posts: 7231
- Joined: Tue Dec 06, 2005 8:31 am
- Location: Suffolk, England
Re: '66 JTM 45 block end vs GPM 45040
MacGaden wrote:Very cool video, George. And block ends are just cool... Dare we ask for a block end JTM50 ? Neil has a cool one you can clone....
Neil
-
VelvetGeorge
- Site Owner
- Posts: 7233
- Joined: Tue Oct 14, 2003 5:12 pm
- Just the numbers in order: 13492
- Location: The Murder Mitten
- Contact:
Re: '66 JTM 45 block end vs GPM 45040
Well played MacG. This could be the makings of a Worldwide alliance replica project. 
george
george
-
NY Chief
- Wiki Editor
- Posts: 6589
- Joined: Thu Apr 28, 2005 6:02 pm
- Location: SoCal
Re: '66 JTM 45 block end vs GPM 45040
Damn that sounds dead on. Anybody notice George's wiring is much neater than the 'real thing" 
NY Chief 5-0, transplanted in SoCal
"Book 'em, Dan-o!"
"Book 'em, Dan-o!"
-
neikeel
- Senior Member
- Posts: 7231
- Joined: Tue Dec 06, 2005 8:31 am
- Location: Suffolk, England
Re: '66 JTM 45 block end vs GPM 45040
Yes, it's much neater!
In response to this I A-B'd my 65 with my Metro clone. Very similar results.
The Metro is cleaner and crisper at lower volumes, does not bloom in the same way that the old amp does. Both running similar Brimar/Mullard pre amp tubes and GEC KT66s. The metro does have a Mullard GZ34 and the Marshall a pinnacle
Interesting that when you get the Metro up to 9 or 10 on the dial it really gets cooking and is a little louder and rockier without losing any , kudos to GM!
Difference probably comes down to the filter caps, the resistance of the pots and possibly the rectifier.
In response to this I A-B'd my 65 with my Metro clone. Very similar results.
The Metro is cleaner and crisper at lower volumes, does not bloom in the same way that the old amp does. Both running similar Brimar/Mullard pre amp tubes and GEC KT66s. The metro does have a Mullard GZ34 and the Marshall a pinnacle
Interesting that when you get the Metro up to 9 or 10 on the dial it really gets cooking and is a little louder and rockier without losing any , kudos to GM!
Difference probably comes down to the filter caps, the resistance of the pots and possibly the rectifier.
Neil