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JMF Spectra 212-7

1/21/2001 5:43 PM
Red G.
JMF Spectra 212-7
Hi everyone.. I got a JMF Spectra 212-7 amp about a month ago, and I can't find any info about it anywhere.. I've searched the net for hours and hours only to come up empty handed.. The only thing I know about this amp is that it's LOUD and it's an old tube amp.. I'd appreciate any info that anyone has.. Thanx in advance.
1/21/2001 7:03 PM

I used the Spectra 60 1x12 for 3 years. (Your amp's little brother. My buddy bought the 2x12 Spectra the same day I bought the 1x12.) It was a nice small club gig amp built by Dean Markley under the Spectra name (early 80s). Mine was a 3x 12AX7 pre-amp and 2x 6L6 output Channel Swithcer. It sounded like crap until I replaced the Pyle(of$hit) speaker with an EV Force12. It really came alive then. I never looked to see how the amp was biased ... I didn't know how at the time, but I remember that it ran so HOT temp. wise, that the output tubes actually turned grayish-black ... it still works though, my brother-in-law has it now & he loves to crank it up to bother his neighbors ... yes it is a loud amp! It was also a pretty thin sounding amp, but that seemed to work very well, since I was playing in a six piece band at the time & it cut through their "orchestrated mayhem" pretty well!  
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1/21/2001 8:56 PM
Red G.

Thanx for the info, Lee. This one seems to have a pretty good low end to it. I usually play my ESP M-107 7 string through it, and it sounds pretty good, as far as not rattling like the little Lainey amp I have. But, I have to admit, the reverb isn't as good as the dual spring in my little Squier Champ. Oh, I have another question about this amp.. Well actually several.. How do the Gain and Master on Lead work, and the 120/60 switch, and the POL switch.. This is my first tube amp (other 2 were solid-state), and I don't really know much about tube amps at all... Except that they sound excellent :) Thanks again for the info.
1/21/2001 10:03 PM

I hope I can answer your questions, but I have to make a couple of disclaimers:  
#1 I haven't played that amp since late 80's so I hope I remember correctly.  
#2 Those amps were good but I do remember that no two sounded the same ... (i.e. quality control must have been lousy!)  
Gain & Master: I don't remember, but I think the gain controls the amount of gain into pre-amp that runs the overdrive channel. The master controlled the over-all level of the overdrive channel of the amp ... somesuch idea, anyway ...  
120/60 Switch: supposedly gave 1/2 power option. It was supposed to cut out two of the power tubes, (I didn't have that switch on mine.) I believe that amp was rated at 120/60 watts depending on this switch setting.  
POL switch: Don't remember ... ("Pull Out Last, Put Out Lights???") ;)  
The 2x12 speaker will give you more bottom, but if they're the old Pyle stock speakers, I'd give 'em the boot and use anything good like JBL or EV and you'll not believe what this amp can do. For a cheapy, It made me a lot of giggin' money for quite a while, and kept up with the other guy's & their big name amps 'til I could afford my big name stuff, too ... (They called mine the "Booger" ???)  
I would have a qualified tech look at it for you and bias it correctly. I think this amp had a lot of potential for a cheapy!  
Hope This Helps Some!  
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