Can I use a Bassman 70watts PT and OT for a Deluxe reverb?

[Ronnnnie]

Hi There,

I have a Fender Bassman 10 (70 watts - 4 x 10") that is too clean for guitar so I am looking to build a Deluxe Reverb into the Chassis.

Can I use the Power & Output transformers for the Deluxe Reverb build?
The Codes are these:
PT: 125P5DX (02280)
OT: 021848

I think these would be OK for a Vibroverb or a Super reverb build, am I correct?
Would prefer a Deluxe Reverb build but what do you suggest on building into this chassis?
Looking for a not-too-loud and early break-up sound.

Thanks! Ron

[pdf64]

It depends how closely you want your build to comply with the design of a Deluxe Reverb.
On the face of it, neither transformer aligns with the DR spec.
Why have you chosen a DR, rather than eg a Super Reverb 70 https://el34world.com/charts/Schematics ... tr_rev.pdf

How about building a Dumble style amp with it?
Your amp would probably be a very suitable platform for that https://www.aaelectronicspcb.com/produc ... pecial-pcb

[Ronnnnie]

I already built a Dumble AMP... #102

Went smooth and was lot's of fun so now I am thinking of redesigning the old Bassman 10 and reuse the Transformers in order to save cost.

So it would be better to go for a Super reverb or is a Tweed Bassman a better option?

[dorrisant]

Maybe you could build it with the TX set you have and add a Lar-Mar type MV if that helps... quicker breakup at a lower volume.

You must not want much more dirt if switching from the Bassman circuit to the DR.

[Reeltarded]

Isn't this a late silver model with UL taps on output?

[chaccmgr]

the DR reverb has trannies that are undersized for the circuit by design, esp. the PT
this leads to sag and compression which makes an important part of the DR's sound and feel

if you build it with way oversized trannies, you will lose that. The preamp should be probably quite similar between a DR and a bassman, the result might still sound pleasant, but it won't be a DR

Another issue will be the voltage on the power tubes wich is supposed to be too high for the 6V6s of the DR

[didit]

Hello —

The simple answer to your question should be clear by now. Nope.

Looking for a not-too-loud and early break-up sound.

Buy a Deluxe or Princeton transformer set, plus a Princeton or Deluxe chassis; and follow more or less directly Martin Manning’s Deluxe build thread. Depending on goals and finances keep or sell that Bassman 10.

..

[pdf64]

Isn't this a late silver model with UL taps on output?

Not from those transformer codes, they match this earlier version https://el34world.com/charts/Schematics ... man_10.pdf
Still super high HT voltage though.
I seem to recall that the OT there is surprisingly wimpy.

[Stevem]

Yes, all the silverface 70 and 135 watt amps where Ul and as such not what you want it your looking for a true Deluxe playing feel and response .

[sluckey]

The Bassman 10 is a silverface amp, but it's 50 watts, not 70 watts. And it is not a U/L amp.

[pdf64]

Yes, all the silverface 70 and 135 watt amps where Ul and as such not what you want it your looking for a true Deluxe playing feel and response .

To describe those OTs / output stages as UL implies that their design has been optimised for linearity.
As the taps are at about 12.5%, my understanding is that's probably not the case.

Whatever, as noted, the OT refered to in post 1 is intended for regular pentode operation, see the schematic link.

[Smitty]

I don't think you need transformers. Those are two really good transformers for a build. I think they're the same as the bantam bass amp. I've got two bantams and have done the ultraphonix mod to both them. I also changed to regular speakers. One has a Jensen 15 and the other has a Jensen 12. Everyone is surprised at how good my Bantams sound.

If I remember correctly Fender tied off the yellow rectifier heater leads in those amps so all you have to do is punch out the chassis (half way done from the factory), add a socket and you've got a tube rectified amp. Where you want to invest your money is in speakers. There are lots of good 8 ohm 10s out there. That will really wake up that amp. Wire them series parallel for 8 ohms.

A quick and easy mod would be to convert the phase inverter to a 12AX7. If the idle current is low you can also change the bias feed resistor from 3.3K to something lower like 2.7K to warm up the amp . Then move the the master volume to the second channel with the mid control. Run the first channel without a master. Two channels. One clean one dirty. Do you have an A/B pedal?

If you ran 6V6 output tubes you'd get around 18 to 20 watts with a 4K load (I like that sound). Or you could source 16 ohm 10s for a 16 ohm load which would translate to 8K.

[JD0x0]

I would think those voltages will be way high for 6V6's.

Maybe consider just modding the Bassman to have less headroom? Bias the PI like a Marshall, remove the NFB from the PI. Increase the midrange pot to 100kA and adjust the B+ dropping resistors to lower the preamp voltages a bit. Post PI MV. Maybe a cathode bias switch to drop down power a bit?