50 watt lead or JTM45

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Spunky99
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50 watt lead or JTM45

Post by Spunky99 »

I dug this out of my closet and decided to complete it.
Not sure if I want a JTM45 or a 50 watt Super Lead or something else.

I don't know what Mfg the PT is. Marked as 1202-018 and 9960622 under it. The OT is a Drake 784-139 NOS and the choke is a MM Toneclone MC10H.

It's sitting on a Weber chassis but I can change that as I've not touched anything yet.

Any suggestions on what build I should do?

BTW: I got the Drake 10 years ago. Not sure what year it is.
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Colossal
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Re: 50 watt lead or JTM45

Post by Colossal »

I'm kind of concerned with the proximity of that OT to the PT. You could try the headphone trick to determine if it will be an issue. Honestly, I would get them apart even if it means another chassis.
tictac
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Re: 50 watt lead or JTM45

Post by tictac »

Put the choke were the OT is and the OT where the choke is....

TT
Spunky99
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Re: 50 watt lead or JTM45

Post by Spunky99 »

:D That might work.
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Reeltarded
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Re: 50 watt lead or JTM45

Post by Reeltarded »

-139 3k4
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
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Littlewyan
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Re: 50 watt lead or JTM45

Post by Littlewyan »

From here it looks like you've got the chassis that has 3 octal holes instead of 4. So may be easier to build a JTM50 with solid state rectifier. You could still build a JTM45 and just have two cap cans inside, others have done that. Either way you're gonna be using EL34s for this build.

Need to sort that Transformer situation first.
Spunky99
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Re: 50 watt lead or JTM45

Post by Spunky99 »

Thanks Littlewyan,
Since it is a Weber chassis, they use this dual Cap Can thing so that is why there are only 3 octal holes.

I'm leaning towards a lead 50 plexi build.
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Reeltarded
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Re: 50 watt lead or JTM45

Post by Reeltarded »

I always try to steer everyone away from tube rectifiers. Just another thing to go wrong during battle without spares on hand or 5 JJs in a row explode into a magnificent display of "wish it was a real Mullard".

:)
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
Spunky99
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Re: 50 watt lead or JTM45

Post by Spunky99 »

But the sag is so beautiful to the ears.....
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Reeltarded
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Re: 50 watt lead or JTM45

Post by Reeltarded »

What sag? If you walk away and come back in 15 minutes I'll prove you can't tell with a $400 real tube vs $1 silicon. Same settings. Olaying with the filtering and the choke cand make all that happen in a much more transparent feeling way.
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
Spunky99
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Re: 50 watt lead or JTM45

Post by Spunky99 »

I see your point Reeltarded

I heard a huge difference in my Dual Rectifier and always ran it on the tube rectifier. It was a really huge difference when playing bluesey to metal crunch. I only used the solid state rectifier if I was playing really clean tones.

In my Valve Junior build I used FREDs as it is solid state.
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Reeltarded
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Re: 50 watt lead or JTM45

Post by Reeltarded »

Yeah, in that boogie it does something, dut'n it? It does. I am not aware of what they do there but is it only rec swap?

I don't work on those amps for love or money.
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
tictac
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Re: 50 watt lead or JTM45

Post by tictac »

Putting a diode between each B+ winding and the tube rectifier adds some protection for the tube rectifier....

TT
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gui_tarzan
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Re: 50 watt lead or JTM45

Post by gui_tarzan »

But those Boogies are soooooooooooo cool!!!

What a nightmare inside the box though. Yuk.
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pdf64
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Re: 50 watt lead or JTM45

Post by pdf64 »

The 784-139 OT can be mismatched to put a 6k8 load on the power tubes, which seems to work fine for KT66 or EL34.[/quote]
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