A Tale of Two Maggies - Magnavox 9300 Series Amplifier Repair 

Admirable the elegant composure and calm scholarly detachment exhibited when confronted with prior intrusions. On other channels dedicated to repair & restoration: "SOMEONE WAS IN HERE BEFORE!!" [as if a chassis was King Tut's chambers]. Bark! Bark!!". But here: "let's see if this is some kind of improvement to the circuit..." Very special! ;-)

I shipped these amps. I received them both in the shape they were in. I just did not have the time or desire for them. lol The purchaser said he was sending to you. I am glad to see they're getting worked by you. Great video.

Nice work, Mark. Very educational following along as you unravelled the “mods”.

Fascinating. I just bought the amp in this video from the owner that sent it to Blueglow. I ran across this video while trying to learn more about the 9300 series. It's currently running off of an AR LS17SE to a pair of AR2ax drivers and sounds pretty dog gone good. Small world.

12AX7 would be the correct replacement for 6EU7, not AU7. The 6EU7 initially had been developed as a replacement for 12AX7 in attempt to reduce hum. Same tube with different pin assignment. Non tapped 6.3 filament brought to pins 1 & 2. BTW enjoyed this video very much as well and hope the client will be happy with this fine amplifier.

Great video Mark !

Problably jumpered the transformer wires to get rid of that fuse blowing all the time and burned the primary because of that silliness.

That was fun. Only thing I do in these cases is cut a hardboard base and add some rubber feet. Saves fingers slipping inside when moving the thing. Here in the UK with our 240 it is even more of a wise move. Of course if it's mine I don't bother....

Power transformer is not hard to substitute, Value is in the audio transformer and the chasis. can be fixed with replacement transformer

Hi Mark, Can you ask that artist if there are any Way to purchase their track. Preferably digital copy of it.

You mention the "noise capacitor" -- I'm trying to figure out how to refurb/update a 1957 Maggie amp and the power cord first- replacing it w/ a modern TV or computer male/female cord, and work a fuse into that.. Anyhow I removed the "Death Cap" as many call it and -will a magnet-tube sort of EMI filter work as well as that cap? trying it is .. not something i've done, haha, the damn thing's sitting there.

Great video! Great fun! I have a Marconi amp and receiver from a console as well. It looks almost identical with four 6BQ5's and 2 6C4 in the front end. I'm trying to restore it. Cap job etc. Before I go out and buy a tube tester, I'm wondering if anyone has any Idea why the two 6C4's are not lighting up? Everything else seems to be working.

If there was feedback pulled from plate of the output tubes then someone could have tried to add shunt feedback to lower the output impedance

Thanks for the great video, was wondering the best way to contact you? I am just getting into tube amps and pre amps and bought a 9300 amp and pas 2 pre amp. I have some questions for someone that can explain their knowledge. Would you be able to help me?

I have to say. You have a very calming voice. I have a Marconi stereo phonograph(amp and am/fm. It looks very similar to those Maggies. However, my unit has output transformers with 4 ohm o/p impedance. Are those Maggies 4 or 8 ohm?

I just found one of these 9302. Do you think it’s worth it to fix up as a main stereo? Is it quality sound?

where can i get a schematic for the 9300's?

BLUEGLOW ELECTRONICS, if the B+ voltage is at 450vdc and you increase it to 600vdc will this increase the AC ripple voltage and output wattage of the amplifier?

that transformer can be rewound if you have the proper equipment. i think there are still places that do that.

Did you say RCA jacks?