JCM800 4212 Tubes?

[spleenharvester]

Hey all.

Anyone know the amount/type of tubes needed in the JCM800 4212, and if it would need rebiasing if I got matched sets?

I'm about to drop £290 on one, the seller tells me it's all working fine and none of the tubes are going, but I figure they'll go sooner or later anyways so I need to be prepared. Looks to be quite a hefty sum to replace all tubes? How often will I need to?

Also, any other tips as to buying an amp of this age/price? Things I should watch out for? I'm gonna try it out after I've bought it to make sure it's all working okay etc. Going to be my amp for several years.

Cheers

 

[Edgecrusher]

Re: JCM800 4212 Tubes?

Its gonna have 4 ECC83's and 2 EL34's. Odds are it will need to be rebiased when you do swap the tubes. Tube life varies widely due to quality and usage. If your playing loud 6 days a week on junk tubes they will only last 6 months or so. Good tubes played at moderate volumes 3 times a week will probably last you 2 or 3 years maybe more.

Think looong and hard about this one though. If you can check it out first. They are HEAVY might be heavier than your willing to lug around they are also LOUD. They sound like poop if played on 2 and 2 will probably get you kicked out of your apartment. There were 2 versions of this amp the earlier on had an issue where the distortion channel bled through the clean channel so when you were playing clean you had this sounded almost like a 2nd amp through the same cab at a lower volume distorted. The later version fixed the bleed through issue but the clipping has a definite solid state buzzy sound to it. If it hasnt ever been recapped it will probably need it soon also if its been played a lot in these past 30 years or so its been around the transformers are probably pretty high mileage too or may have already been replaced.

Some people like this version of the JCM800 but to me its not one of the better. The first version sounds much more like a classic marshall but the gain is pretty low you wont notice any extra distortion from the preamp knob until past 8 or so. Then 2nd version has more distortion but still not a lot and like i said earlier has a buzzy quality to it that i dont like. If your in uni and dont have tons of cash and are having a small living space think hard about this one. yes i'm sure the idea of a tube marshall gives you a raging hard on but at this point thinking of the practical side of things might get you much farther and practical and JCM800 never enter the same sentence.

 

[spleenharvester]

Re: JCM800 4212 Tubes?

Wow, a lot of information there mate, thankyou!

-I can't try it out unfortunately since it's quite a drive away and I don't think my lift would appreciate going twice haha.

-Hopefully the tubes in there (who knows what they are) will last until I can sell my VT40+ and get a new set in there.

-As for lugging the thing about - I'm gonna buy a big ass amp trolley for it.

-It will probably sound better than the Valvetronix on 2 I would bet. It's not too hard to top that scratchy solid state DSP goodness lolol.

Honestly I think it will be a long time before I need to upgrade it anyways, my last amps have all been solid state (apart from the Valvetronix of course), so this should serve my needs easily.

EDIT: Oh just a follow up. http://home.roadrunner.com/~theoutpatients/JCM800Chasis.JPG there are only a few electrolytic caps in there, is it worth changing them out?

 

[jmh151]

Re: JCM800 4212 Tubes?

I had a 4211 which was the 100 watter with 4 EL34's- mine was an 89, so it had the bleed through fix.

Soon after I got mine, the sound died. I took it somewhere where they re-tubed it and "serviced" it , which cost $350 (I paid 899 for the amp). Afterwards it sounded much better, but for modern gain levels it would get quite noisy when boosted. When I traded it in, Guitar Center suggested using it as a recording amp since due to the age they wouldn't trust reliability on the road.

I liked it, but it really needed to be cranjed to reach full potential

 

[spleenharvester]

Re: JCM800 4212 Tubes?

Agh, the auction went way higher than I thought, guess that's what I get for putting all my eggs in one basket!

Anyways, plenty more in the sea. Does anyone know how the Laney VC30-210 would compare? I have found one being sold for £240 used.

EDIT: http://www.youtube.com/watch?v=8GUYbxMoPio wow, that sounds pretty good to me.

 

[Lake Placid Blues]

Re: JCM800 4212 Tubes?

Anyone know the amount/type of tubes needed in the JCM800 4212, and if it would need rebiasing if I got matched sets?

Even though you didn't get it, just for the sake of knowing; Marshalls should be re-biased every single time.