JCM800 DIY Build Kit on Ebay: Worth It?

[Wailin' Tele]

http://cgi.ebay.com/JCM-800-2204a-50...d=p3286.c0.m14


Comes with everything but tubes, chassis, cabinet, and speakers. Wondering if it is a good deal, and if so what would the rest of the stuff cost?

[Ben Harmless]

At $329 it seems almost too good to be true. It sort of hinges on the quality of the transformers and choke. I don't know anything about that manufacturer, so maybe someone can fill me in there.

Factoring in cheaper transformers, and the fact that you'll still need to get a chassis, and the cost of the minor specialized tools (turret staking tool, etc) that I bought when I built mine, it comes close to what I paid, but considering that I paid more than $200 for my Hammond iron alone, I have to wonder where the corners are being cut.

[muchxs]

Anything that doesn't include a chassis can't be considered a kit.

Good luck finding a repro JCM800 chassis...

[Flynman]

Go over to www.Metroamp.com the have anything you could possibly need for building a JCM800. Price out what you don't have and then compare it to one of their complete kits or drop in circuit boards. I have built 2 kits from them and they are second to none.


Keith

[muchxs]

Originally Posted by Flynman

Go over to www.Metroamp.com the have anything you could possibly need for building a JCM800. Price out what you don't have and then compare it to one of their complete kits or drop in circuit boards. I have built 2 kits from them and they are second to none.

O.k.. Metro offers their 100 watt master volume kit for $1099 plus shipping. I can buy JCM800 heads for around $1100 each so I'm not sure how excited I can get over a $1k+ "JCM800" kit.

They'll sell you pre-'74 or so repro chassis but no JCM800. Only available as a kit, show up with $1100.

[Flynman]

I could also buy a Tele for less that what I spent to build my last one...So I guess I shouldn't be too excited either?

[Wailin' Tele]

If I did this I'd just build a head. So why is the chassis so hard to get. Stupid question time, can't a metal guy easily fabricate one, or am I missing something?

[Ben Harmless]

I think Muchxs is referring to a chassis that's actually a reproduction of the JCM800 chassis, (with faceplace and everything) vs on that will work just fine for the purpose. I personally went with the medium box from Watts Tube Audio.

[JohnnyCrash]

I'd snatch that in a heartbeat. Add the price of tubes, a chassis, and a cab and you're looking at a HANDWIRED JCM800 for about $600-$800... plus the fun of building it and the learning process.

--

The issue is not finding a cheap chassis, it is this:
If you build with a non-repro chassis, will it fit in a repro head cab?

If you build your own cabs, cool - you can make them fit together. If you don't, then you'll need a chassis that will fit whatever cab you will end up buying.

If you plan on a Marshall smallbox style cab (JTM45, or 1987 plexi50, which is not the larger, "true" JCM800 style cab) you can look for a chassis at least 16.5" wide (cab cutout is 16 and 3/8ths), and one exactly 6.5" front to back).

The depth (top to bottom) will depend on how you mount the power tranny - into a square cutout or standing up. Chassis depth + PT height in whichever config (standup or in cutout) will have to fit in the repro smallbox's 9" height. BUT this is external height, so you have to subtract at least 3/4" from both top and bottom for birch ply thickness (so perhaps 7.5" total height inside the cab)... not to mention the EL34 power tubes standup height on top of the chassis (PT's are usually taller than the tubes though).

So figure on a chassis at least 16.5" (but no more than 24") by exactly 6.5" with a height able to fit a PT on top no higher than 7.5" once the PT and tubes are standing up. Ideally, a repro size for a smallbox headcab

--

Commercial options for chassis/cab.

If you go with Mojo, they only offer JTM45 and plexi style chassis+faceplates - the JCM800 only has two inputs, so you'd have two empty input holes in the front.

I solved this by making my JCM800 two channels and added a Gain control for each channel in the unused input jack holes, turning it into a single input, and adding the front panel channel switch (footswitch jack is in the rear):





For what its worth, Ken at Watts Audio (www.turretboards.com) is awesome and I've used all sorts of his stuff for builds. Coincidentally, right now, I'm using one of his blank chassis in a JCM800 style two channel 2x10" combo build. His Large blank headbox (20" x 6.5" x 2.5") will be better suited to fitting in a smallbox repro Marshall cab.

I've used Ceriatone, Mojo, and Weber chassis+faceplates in three Mojo smallbox headcabs (but any repro smallbox cab will be the same size). The build with a Weber chassis had a standup PT (since his cheapy PT blew up, I replaced it with an OEM style Hammond replacement), I've also used a standup on the Mojo chassis... no problems there. So I'd think that kit has a typical sized PT that could standup no-problem on a 2.5" high chassis.

You can see all three here:





Top left is my 50w plexi, Mojo chassis and their orange colored cab - my BEST sounding Marshall hands-down! Under that is my dual channel JCM800/2204 build with Weber chassis (both are all tube, unlike real 2 channel JCM800's) in a classic black Mojo cab, and to the right is my Vox AC30 (with halfpower AC15 switch) in the red Mojo cab (that one used a Ceriatone Marshall style chassis).

[Wailin' Tele]

Originally Posted by JohnnyCrash

I'd snatch that in a heartbeat. Add the price of tubes, a chassis, and a cab and you're looking at a HANDWIRED JCM800 for about $600-$800... plus the fun of building it and the learning process.

--

The issue is not finding a cheap chassis, it is this:
If you build with a non-repro chassis, will it fit in a repro head cab?

If you build your own cabs, cool - you can make them fit together. If you don't, then you'll need a chassis that will fit whatever cab you will end up buying.

If you plan on a Marshall smallbox style cab (JTM45, or 1987 plexi50, which is not the larger, "true" JCM800 style cab) you can look for a chassis at least 16.5" wide (cab cutout is 16 and 3/8ths), and one exactly 6.5" front to back).

The depth (top to bottom) will depend on how you mount the power tranny - into a square cutout or standing up. Chassis depth + PT height in whichever config (standup or in cutout) will have to fit in the repro smallbox's 9" height. BUT this is external height, so you have to subtract at least 3/4" from both top and bottom for birch ply thickness (so perhaps 7.5" total height inside the cab)... not to mention the EL34 power tubes standup height on top of the chassis (PT's are usually taller than the tubes though).

So figure on a chassis at least 16.5" (but no more than 24") by exactly 6.5" with a height able to fit a PT on top no higher than 7.5" once the PT and tubes are standing up. Ideally, a repro size for a smallbox headcab

--

Commercial options for chassis/cab.

If you go with Mojo, they only offer JTM45 and plexi style chassis+faceplates - the JCM800 only has two inputs, so you'd have two empty input holes in the front.

I solved this by making my JCM800 two channels and added a Gain control for each channel in the unused input jack holes, turning it into a single input, and adding the front panel channel switch (footswitch jack is in the rear):





For what its worth, Ken at Watts Audio (www.turretboards.com) is awesome and I've used all sorts of his stuff for builds. Coincidentally, right now, I'm using one of his blank chassis in a JCM800 style two channel 2x10" combo build. His Large blank headbox (20" x 6.5" x 2.5") will be better suited to fitting in a smallbox repro Marshall cab.

I've used Ceriatone, Mojo, and Weber chassis+faceplates in three Mojo smallbox headcabs (but any repro smallbox cab will be the same size). The build with a Weber chassis had a standup PT (since his cheapy PT blew up, I replaced it with an OEM style Hammond replacement), I've also used a standup on the Mojo chassis... no problems there. So I'd think that kit has a typical sized PT that could standup no-problem on a 2.5" high chassis.

You can see all three here:





Top left is my 50w plexi, Mojo chassis and their orange colored cab - my BEST sounding Marshall hands-down! Under that is my dual channel JCM800/2204 build with Weber chassis (both are all tube, unlike real 2 channel JCM800's) in a classic black Mojo cab, and to the right is my Vox AC30 (with halfpower AC15 switch) in the red Mojo cab (that one used a Ceriatone Marshall style chassis).

Holy s**t can I come over. That's like showing candy to a kid.

Great info BTW, Ill be PMing you when I get chance. Thanks for the post.

[markito787]

Originally Posted by Wailin' Tele

http://cgi.ebay.com/JCM-800-2204a-50...d=p3286.c0.m14


Comes with everything but tubes, chassis, cabinet, and speakers. Wondering if it is a good deal, and if so what would the rest of the stuff cost?

Hey! Im building one theese too! Have you finished yours yet?

[Wailin' Tele]

Haven't even started, life got in the way. Let me know how things go with your build.

[BlueJim]

Originally Posted by Flynman

I could also buy a Tele for less that what I spent to build my last one...So I guess I shouldn't be too excited either?

I don't believe building guitars and building amps compares in an apples-to-apples sense, at least not for me. I work on my guitars to make a guitar I like more than one I can buy for a comparable price. I built an amp hoping I could save money compared to buying one of comparable function.

[EdMax]

FYI,

At one time many decades ago Chicagoland was a Mecca of the tube era electronics. Countless Amp, TV, Stereo and component companies were at the forefront.

This transformer company dates back to the Supro era and has been in business at that location forever almost.

Anyway, they do indeed make a very good product and the quality is easily on par with the over priced competition.

Check out the shoot-out clips at their website (which is very slow)
http://magneticcomponents.net/HearWh...merFromUs.html

These guys might not be well known, but they are far from being cheap.

[tele4me2]

I Purchased A Fender deluxe 5E3 kit from this company and installed it in a old Crate combo that died on me. It was my first amp build and It sounds great. I would totally trust this company with this kit. If I had the 300 plus cost of tubes I would build my own box and fashion up a chassis for myself.

[guitardude57]

Triode amp kits are a decent buy.......especially the Fleabay stuff......a no brainer on the price for the Marshall kit.