TR JM 50w Build Thread

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TR JM 50w Build Thread

Post by Marshmallow »

About to start the JM amp.

Chassis and parts arrived last week. Restraining myself due to the lack of $$$. :lol: I'll see how I feel this weekend.
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Currently thinking whether to build an oversized speaker cabinet or a standard dumble speaker cabinet to match the head cabinets. :lol:

Poll up
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Last edited by Marshmallow on Fri Jan 15, 2021 3:38 pm, edited 2 times in total.

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Re: TR JM 50w Build Thread

Post by MogwaiBoy »

I'm debating the same thing for my Deluxe Reverb head and I'm leaning towards an oversized cabinet. The head looks and sits more comfy, and from what I gather a bigger cab = bigger sound?

As long as it fits through the side door onto the back seat of my car :)

BTW the DR head is about 610-615 wide anyway, so an "oversized" cab for it will be quite huge! Enough for me to wonder shall I go 2x12.

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Re: TR JM 50w Build Thread

Post by Marshmallow »

MogwaiBoy wrote: Thu Jan 14, 2021 8:16 am I'm debating the same thing for my Deluxe Reverb head and I'm leaning towards an oversized cabinet. The head looks and sits more comfy, and from what I gather a bigger cab = bigger sound?

As long as it fits through the side door onto the back seat of my car :)

BTW the DR head is about 610-615 wide anyway, so an "oversized" cab for it will be quite huge! Enough for me to wonder shall I go 2x12.
Good question. Bigger cab is definitely bigger sound. I've been trying out different cabs in the shop too. In terms of two rock cabinet design, an oversized open back 112 and a standard open back 212 sounds surprisingly similar to my ears and just as loud. The bass, the mid is just a tad bigger for the 212 but otherwise the same unless you have 2 different speakers inside your 212. For a 40w amp like yours, you might find it pleasing when you push a single speaker a little more in an oversized cabinet. I find 212 too heavy to move around. :lol:

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Re: TR JM 50w Build Thread

Post by Bg »

Marshmallow wrote: Thu Jan 14, 2021 1:58 pm
MogwaiBoy wrote: Thu Jan 14, 2021 8:16 am I'm debating the same thing for my Deluxe Reverb head and I'm leaning towards an oversized cabinet. The head looks and sits more comfy, and from what I gather a bigger cab = bigger sound?

As long as it fits through the side door onto the back seat of my car :)

BTW the DR head is about 610-615 wide anyway, so an "oversized" cab for it will be quite huge! Enough for me to wonder shall I go 2x12.
Good question. Bigger cab is definitely bigger sound. I've been trying out different cabs in the shop too. In terms of two rock cabinet design, an oversized open back 112 and a standard open back 212 sounds surprisingly similar to my ears and just as loud. The bass, the mid is just a tad bigger for the 212 but otherwise the same unless you have 2 different speakers inside your 212. For a 40w amp like yours, you might find it pleasing when you push a single speaker a little more in an oversized cabinet. I find 212 too heavy to move around. :lol:
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So, is that low alcohol or no alcohol at all? mmmm, no alcohol, do you want to try it? Noooooooooo.

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Re: TR JM 50w Build Thread

Post by Marshmallow »

Bg wrote: Thu Jan 14, 2021 2:15 pm
Marshmallow wrote: Thu Jan 14, 2021 1:58 pm
MogwaiBoy wrote: Thu Jan 14, 2021 8:16 am I'm debating the same thing for my Deluxe Reverb head and I'm leaning towards an oversized cabinet. The head looks and sits more comfy, and from what I gather a bigger cab = bigger sound?

As long as it fits through the side door onto the back seat of my car :)

BTW the DR head is about 610-615 wide anyway, so an "oversized" cab for it will be quite huge! Enough for me to wonder shall I go 2x12.
Good question. Bigger cab is definitely bigger sound. I've been trying out different cabs in the shop too. In terms of two rock cabinet design, an oversized open back 112 and a standard open back 212 sounds surprisingly similar to my ears and just as loud. The bass, the mid is just a tad bigger for the 212 but otherwise the same unless you have 2 different speakers inside your 212. For a 40w amp like yours, you might find it pleasing when you push a single speaker a little more in an oversized cabinet. I find 212 too heavy to move around. :lol:
If you're made out of twigs, then this...

Image
True that. Forgot people use cars in NZ. :lol: I just carry all my gear on the train. :lol:

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Re: TR JM 50w Build Thread

Post by Marshmallow »

After the poll. Two Rock style cabinet it is.

Trying to decide the front bar now.. New Poll up. Two votes each, 1 vote per amp.
Two rock will be finished in black and the ODSR will be finished in suede along with a matching cab. However I'm still waiting for them tolex. Might just rock the pine cab for the time being.

For the Overdrive Special Reverb
Which front bar design?
Two rock/ODS type - wood bar/aluminium
or Ampnation type/ods? - aluminium only

For the JM amp
Two rock/ODS type - wood bar/aluminium
or Ampnation type/ods? - aluminium only
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Re: TR JM 50w Build Thread

Post by Bg »

Marshmallow wrote: Thu Jan 14, 2021 2:50 pm
Bg wrote: Thu Jan 14, 2021 2:15 pm
Marshmallow wrote: Thu Jan 14, 2021 1:58 pm

Good question. Bigger cab is definitely bigger sound. I've been trying out different cabs in the shop too. In terms of two rock cabinet design, an oversized open back 112 and a standard open back 212 sounds surprisingly similar to my ears and just as loud. The bass, the mid is just a tad bigger for the 212 but otherwise the same unless you have 2 different speakers inside your 212. For a 40w amp like yours, you might find it pleasing when you push a single speaker a little more in an oversized cabinet. I find 212 too heavy to move around. :lol:
If you're made out of twigs, then this...

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True that. Forgot people use cars in NZ. :lol: I just carry all my gear on the train. :lol:
Yeah, you're buggered then... helix stomp into PA it is ;)
So, is that low alcohol or no alcohol at all? mmmm, no alcohol, do you want to try it? Noooooooooo.

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Re: TR JM 50w Build Thread

Post by jeremyb »

Definitely go with the two rock look!!
Slowy wrote: That's the problem; everything rewarding is just such hard work. Regret takes much less effort.

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Re: TR JM 50w Build Thread

Post by Marshmallow »

jeremyb wrote: Thu Jan 14, 2021 4:26 pm Definitely go with the two rock look!!
For the JM amp? :D or both? :D

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Re: TR JM 50w Build Thread

Post by jeremyb »

Marshmallow wrote: Thu Jan 14, 2021 7:34 pm
jeremyb wrote: Thu Jan 14, 2021 4:26 pm Definitely go with the two rock look!!
For the JM amp? :D or both? :D
For the JM amp of course!
Slowy wrote: That's the problem; everything rewarding is just such hard work. Regret takes much less effort.

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Re: TR JM 50w Build Thread

Post by Marshmallow »

jeremyb wrote: Thu Jan 14, 2021 7:55 pm
Marshmallow wrote: Thu Jan 14, 2021 7:34 pm
jeremyb wrote: Thu Jan 14, 2021 4:26 pm Definitely go with the two rock look!!
For the JM amp? :D or both? :D
For the JM amp of course!
Done. haha :lol:

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Re: TR JM 50w Build Thread

Post by Marshmallow »

ODRS 50w - > Cabinet with aluminium bar only
TR JM 50w - > Cabinet similar to Two Rock

TR starts on Monday.

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Re: TR JM 50w Build Thread

Post by Marshmallow »

Completed. JM amp is also one of the most documented amplifiers. Man, this amp is crazy. The harmonics, the response, the clean sound is just pure awesomeness. Could possibly be one of my favourites apart from the ODS. Only thing that was different from this and the original circuit is the half power switch, parallel speaker outs, speaker impedance selector and the 3 spring goodness rather than the 2 springs.

Vox speaker grille also just arrived after 3 months of waiting! Did a quick cut and staple. Only took about 10 mins. The quality is also worth 10 mins. :lol: Tolex is nowhere to be found though.

Enjoy.

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Re: TR JM 50w Build Thread

Post by jeremyb »

Epic.
Slowy wrote: That's the problem; everything rewarding is just such hard work. Regret takes much less effort.

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Re: TR JM 50w Build Thread

Post by StrummersOfThunder »

Absolutely gorgeous ....pristine layout and workmanship
Congratulations , that looks like a forever amp to me .

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