Gibson EH-125

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Phil_S
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Re: Gibson EH-125

Post by Phil_S »

Wow, I'm shocked to see the voltages on the 6SJ7, Va=39 Vg2=16. I had no idea you could run a tube at such low voltages and get that kind of tone. When I built the GA-20 circuit, it was muddy. I did a few things to raise the plate above 100v and that helped a great deal. In this case, the tone is just outrageously grand. Really, really nice job.
bluesfendermanblues
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Re: Gibson EH-125

Post by bluesfendermanblues »

ic-racer wrote:Overdriven sounds EH125:
https://youtu.be/b4xgKfXheEU

Clean sounds EH125:
https://youtu.be/IaYIE8olw28
Great clean sound -what guitar?
Diva or not? - Respect for Mr. D's work....)
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ic-racer
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Re: Gibson EH-125

Post by ic-racer »

The clean sounds were done with a 1993 Telecaster . When I started playing guitar that would have been like having a 1956 Telecaster.
"You feel like you're floating on a football field filled with marshmallows." -Dumble
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ic-racer
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Re: Gibson EH-125

Post by ic-racer »

Not shown yet on the schematic is the fact that the only grounding input jack is the one for "Microphone," which is the one attached to the volume control.
So, if the guitar is plugged in there, the other two jacks are 'open' and can pick up noise.

Rather than alter the amp, I just made a shorting 1/4" Phone plug and plug that in one of the "Instrument" jacks.
"You feel like you're floating on a football field filled with marshmallows." -Dumble
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ic-racer
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Re: Gibson EH-125

Post by ic-racer »

Just finished the guitar that goes with this amp.
[img:1024:768]http://img.photobucket.com/albums/v670/ ... nished.jpg[/img]
"You feel like you're floating on a football field filled with marshmallows." -Dumble
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rp
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Re: Gibson EH-125

Post by rp »

Oh my. I need a cold shower.
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ic-racer
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Re: Gibson EH-125

Post by ic-racer »

This is a clip of both the guitar and amp together.
https://youtu.be/f4tcIQXNC2E
"You feel like you're floating on a football field filled with marshmallows." -Dumble
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ToneMerc
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Re: Gibson EH-125

Post by ToneMerc »

ic-racer wrote:This is a clip of both the guitar and amp together.
https://youtu.be/f4tcIQXNC2E
Very nice, you are a true artist with your work as well.

TM
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ic-racer
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Re: Gibson EH-125

Post by ic-racer »

Nine years leater and the amp needed some work.

The cardboard in side the field coil deteriorated. That, in combination with rust on the metal cylinder, caused the original voice coil to tear apart.

I did try to fix it again, but the busted voice coil, combined with that very old paper cone were at the point of being un-repairable.
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"You feel like you're floating on a football field filled with marshmallows." -Dumble
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ic-racer
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Re: Gibson EH-125

Post by ic-racer »

I tried to clean out the deteriorating cardboard residue from inside the field coil. I then tried to seal it with lacquer.
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"You feel like you're floating on a football field filled with marshmallows." -Dumble
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ic-racer
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Re: Gibson EH-125

Post by ic-racer »

In the end I wound up removing the output transformer (which was attached to the basket of the field coil speaker) and I had already removed the field coil.

I attached both the field coil and the output transformer to a ceramic speaker and bid farewell to the original speaker.
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"You feel like you're floating on a football field filled with marshmallows." -Dumble
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ic-racer
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Re: Gibson EH-125

Post by ic-racer »

Lastly, the volume pot had deteriorated, so I replaced that with a new one.
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"You feel like you're floating on a football field filled with marshmallows." -Dumble
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ic-racer
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Re: Gibson EH-125

Post by ic-racer »

"You feel like you're floating on a football field filled with marshmallows." -Dumble
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