JTM 45/100 completed!

[Vegard]

Hi!

I completed the amp today! No problems, works great. Dead quiet when not playing.
Alittle dark sounding. Dont think i like the AB CCs in all positions...

http://i267.photobucket.com/albums/ii28 ... CI0021.jpg" onclick="window.open(this.href);return false;

http://i267.photobucket.com/albums/ii28 ... CI0019.jpg" onclick="window.open(this.href);return false;

http://i267.photobucket.com/albums/ii28 ... CI0018.jpg" onclick="window.open(this.href);return false;

[myfoot]

Nice! Congrats, I think I may use all pink wire for the pots on my next one too.

[MacGaden]

Very nice build, congrats. Let it settle in before you change anything. I had an original block-end JTM45/100 in my house for at few weeks, and it took some time to get used to how different it sounded and felt from any other Marshall I´ve tried..

[Vegard]

Thanks guys! Yes i will give it some hours before i change anything, but i think some CF resistors will be better... to my ears.

[HTH]

I'm intrigued how people seem to use carbon comp resistors in alot of the builds on this website - didn't all but the very earliest of JTM45s use carbon film resistors?

[Vegard]

I have/had a 12xxx with almost only CF resistors.Very good sounding! Then i changed to AB CCs to all the positions because i belived that was the thing! But the amp just lost it...

[Wayne]

Wow !
Almost as good as mine !!!

Seriously - awesome looking build - Brians boards ??

What plate volts did you end up getting on V2 ?
and what pre amp tubes did you end up using ?

Mine was around 360 and i've been a little worried about it for a while - but all seems ok still after a month or so.

I absolutely LOVE the sound of these things.


Wayne

[Vegard]

Yes, thats Brians boards! Theyre beautiful!

I have JJ in V2 and Sylvanias in V1 and V3 !
Let me check Vp on V2 tomorrow, i dont remember exactly : )

Wayne, what have you noticed during the break in of the amp?

[Drifting]

You guys are KILLING ME!!!!!!!!!!!!

I so wish I had the money to start this build

Does the 45/100 have the same bass characteristics as a 45, or can you push the bass some more before getting flubby?

Brian's boards do look awesome, they will be in my next build...

Is the block logo or script logo considered to be correct for a 45/100 or can it go both ways? I can't really pin it down either way for memory.


Every time I watch this and look at the 45/100 section my need to build this amp gets significantly worse:

http://www.youtube.com/watch?v=gYwZ8I8wOGA" onclick="window.open(this.href);return false;

[Wayne]

Yes, thats Brians boards! Theyre beautiful!

I have JJ in V2 and Sylvanias in V1 and V3 !
Let me check Vp on V2 tomorrow, i dont remember exactly : )

Wayne, what have you noticed during the break in of the amp?

I really have not had the chance to crank it yet. Neighbours - you know !
It has smoothed out a bit if anything - but it would not have 20 hours on it yet. It sounded great straight up. It just seems to have more balls than the JTM45 - even at lower / comparative (is that a real word ?) volumes. You know what i mean ?
It just sounds huge.
I'd say mine is almost the same as yours - spec wise. Mustards & CC's, filtering looks identical though I do have the dual 32uF on board with an extra 10k to V1. I might disconnect one leg on this at some stage just to see if there is much difference. I used the erie coz it looked cool ! (sad - but true).
I have all JJ's in the preamp.

Hey Drifting.
As mentioned above it just sounds huge - but definately not flabby. I've got to get it out of here so i can push it a bit and see what happens. I don't have an attenuator but have used pedals on it to get a gainier sound and it does sound fantastic.

Well worth building in my opinion. It's now my favourite.
Not sure about the block logo or script either. I just copied one that i saw on amparchives which had the script logo. The re issues have a block logo though. Either way - i don't think it matters. Looks good both ways !

Wayne

[axeman]

Wow, Elite BUILDER.

[Drifting]

Sweet yeah, you aren't the first person I've heard say that either,

Everyone seems to have a hard time quantifying what makes a 45/100 a 45/100, but I recall older posts dubbing it a 45 with more balls!

And it's got the most headroom of any Marshall.

[Roe]

try a 270pf cap in the tone stack - early 45s and 100s used this value. It gives a little more brightness. also, ceramic caps can give some more edge and dirtiness.
get rid of those 100k CCs

[VelvetGeorge]

Looks fantastic Vegard!!!! Bravo!

I agree with Neil, let it break in a bit before you rip out all of those AB's.

george

[Vegard]

Thanks George! : ) Ill break it in before i change anything!

Wayne, my Vp on V2 is also 360V! And it also says 360 in the Voltage diagram...