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JL Sargent

Separating good tube amp from an otherwise bad Magnavox console.

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History: Stopped at the thrift store today. What was I thinking? Oh well, I found an old '59 stereo Magnavox console, all tubes. Tag said it worked. Price was $6.49. So I brought it home, plugged it up and sure enough it kinda worked. Looks like two 6BQ5s for output tubes. I connected my MP3 player to the amps RCA type connectors and sure enough it sounded good.

So I'm thinking how easy can this be for an amp pull. The 120v plug goes straight in the amp so I'm thinking I can just unplug the wiring harness to the rest of the console and all will be good, WRONG. It won't do squat with that harness disconneced much to my disappointment. What to do next?

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History: Stopped at the thrift store today. What was I thinking? Oh well, I found an old '59 stereo Magnavox console, all tubes. Tag said it worked. Price was $6.49. So I brought it home, plugged it up and sure enough it kinda worked. Looks like two 6BQ5s for output tubes. I connected my MP3 player to the amps RCA type connectors and sure enough it sounded good.

So I'm thinking how easy can this be for an amp pull. The 120v plug goes straight in the amp so I'm thinking I can just unplug the wiring harness to the rest of the console and all will be good, WRONG. It won't do squat with that harness disconneced much to my disappointment. What to do next?

The wiring harness probably has 120 volts going to the pre-amp. And in order to complete the connection to the primary taps of the power supply transformer, the plug has to be connected.

The PS primary wires are going to be both black, or one black, and one red and black striped one. Both the primary taps should go to that plug to the wiring harness. You may just be able to use a jumper wire to get power to both primary wires.

Or if you plan on using the amplifier for stand alone use, you may as well find the primary wires, wire a fuse/fuseholder, and a power switch on the line side.

If that's the single-ended 6BQ5 Magnavox with the 5U4 rectifier tube and choke in the power supply, it's a good sounding little amp to keep around.

I have my black SE maggotbox going on my LaScalas now......It's a poor man's triode amp.....

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Thanks, thats what I suspected. A daisy chained 110v basically. Yes, its single ended 6BQ5s with the 5U4 tube. I'm guessing a 2 amp fuse?

I'm hoping to use it with my Heresys.

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That is a nice looking amp! I think its the exact amp I have. Your handling of the old socket hole and the new speaker terminals have inspired me. How did you get the output transformers to look so good? They look like they've been polished with a cotton wheel.

Thanks for sharing that.

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That second picture has really jump started me this afternoon. I located the two primarys for my power trans. I pulled them and tested, ok. I then pulled the old socket and removed all the extra wiring associated with it. Well on my way here. Now I really appreciate how much work you have in that one.

Geeze, you must of had those output transformers chromed! Mine will never look that good!

What about impedance? Are these original transformers ok with my Heresy 8 ohm speakers?

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I'm pretty sure the output transformers are around 4 ohms. I have two of the little amplifiers. I've used my other little Magnavox SE 6BQ5 on my Cornwall's and LaScalas with good results.

I've never listened to the amplifiers using Heresies, I imagine it should be ok.

A friend and I listened to one of the amplifiers with a pair of JBL (L20?) Decades. The tone of the amplifier sounded great, but they tend to run out of steam with bookshelf type speakers being around 5 watts per channel. The bigger and more sensitive the better.

The amp was a complete tear-down. I taped off the output transformer windings and wires, and then sanded on the frames. I started with a heavier grit paper, and worked my up to around 1500 grit, until they polished out. It was a chore.

I poured a ton of time into that amp. Dunno why........Well, I wanted to prove to myself that you can take a ugly console pull amplifier and make it into something pleasing with regard to looks.

post-6643-13819437767622_thumb.jpg

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"I wanted to prove to myself that you can take a ugly console pull amplifier and make it into something pleasing with regard to looks."

I'd say you did it![H]

Mine has what looks like a little adjustable pot on top. Whats that? Also my amp is an 8601-20.

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It's either a balance or a hum pot I would guess. The two amplifiers I have never had any balance or hum pots. I have PP Magnavox 6BQ5 amplifier (9300 series) that uses a hum pot.

A friend has a SE 6BQ5 Magnavox 196 series that uses a 12AX7,2 6BQ5,a 5U4 rectifier, and a choke in the PS. The OPT's are a little bit larger. That amp has a hum or balance pot.

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Looks good!

They are nice sounding little amps. It may not be a whole buncha watts, but it's single-ended class A watts.

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Those are just cables that were hanging near my work bench. By the colors Id guess they were intended for video, but in reality they're probably identical to audio cables in function. They just have different colored covers.

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