Brownface Princeton OP Trans in Brownface Deluxe?

guitback1

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Would it be possible to substitute a Brownface Princeton OP Trans in Brownface Deluxe in order to cut the 20 watts or so to around 12? Is that a "no-go" because of voltage problems or other circuitry incompatibility? I love my Brown Deluxe Clone, but due to people trying to bring down stage volumes (me included!), I'd like to have one that isn't quite so loud, but is similar in tone. Yes, having a Brown Princeton in addition to my current amp would be nice, but it'd be pricey. I certainly cannot afford a Fender Chris Stapleton Princeton! I've built a number of amps from kits, so I am reasonably familiar with working under the hood. My Deluxe has nice Mercury x-formers now, and they sound great. However, I really am trying to replicate the sound I have (WITH the GA64 speaker) at a lower volume level. Another question might be..."Is there a speaker that sounds like an Eminence GA64, but is not so efficient?
 

printer2

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How about an attenuator, that way you have the power on tap when you want it?
 
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schmee

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You could do that. But there are inexpensive new trannies that you wont risk killing. I think the actual voltages are high in both amps? ... or are they?

Have you tried just plugging into input 2?
Would a weaker version of the Preamp tube get you there? 12AY7? 12AU7?
How about backing off on the rectifier tube from a GZ34 to a 5Y3?

The Emi does sound great.
 
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guitback1

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You could do that. But there are inexpensive new trannies that you wont risk killing. I think the actual voltages are high in both amps? ... or are they?

Have you tried just plugging into input 2?
Would a weaker version of the Preamp tube get you there? 12AY7? 12AU7?
How about backing off on the rectifier tube from a GZ34 to a 5Y3?

The Emi does sound great.
Thanks for answering schmee! I really love the sound of the Brown Deluxe through the GA64. I live mostly clean(ish). I know, just like everybody else, pretty much where the amp is between 3 to 5 on the volume knob. I love the way the Brownies are somewhat more spanky than a tweed, but still having some of that blackface definition. I'm just hoping to find a way to do this without having to buy an attenuator of some sort. The preamp tube change won't do what I'm looking for, and believe me, I've tried. I just need to knock the amp's volume down to Princeton level. I do have a 5Y3 rectifier tube (or "rectum-fryer" as my fave guitar player refers to them). I imagine the amp would be a little squishier and not quite as loud, but I was afraid to try it before I asked someone who knows it won't destroy anything. So do people actually just "sub" a rectifier for knocking the edge or headroom off?
 

guitback1

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How about an attenuator, that way you have the power on tap when you want it?
Thanks Printer2 for replying. I really was hoping not to have to buy an attenuator, but it does make sense. Maybe nowadays attenuators really don't murder the tone and feel of an amp like they used to.
 

schmee

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Thanks for answering schmee! I really love the sound of the Brown Deluxe through the GA64. I live mostly clean(ish). I know, just like everybody else, pretty much where the amp is between 3 to 5 on the volume knob. I love the way the Brownies are somewhat more spanky than a tweed, but still having some of that blackface definition. I'm just hoping to find a way to do this without having to buy an attenuator of some sort. The preamp tube change won't do what I'm looking for, and believe me, I've tried. I just need to knock the amp's volume down to Princeton level. I do have a 5Y3 rectifier tube (or "rectum-fryer" as my fave guitar player refers to them). I imagine the amp would be a little squishier and not quite as loud, but I was afraid to try it before I asked someone who knows it won't destroy anything. So do people actually just "sub" a rectifier for knocking the edge or headroom off?
Yes you can sub. You should rebias though. A tiny bit of "squish" in the brown cleanness may not be a bad thing.
But a PR tranny could work out for you, I just dont like you risking a vintage brown OT. A lot of vintage Deluxes run very high on plate voltage. Mine run 455-460!
I'm now using a simple "browner" for 115 VAC input.
 

2L man

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Obviously only using volume knob is not enough for you to decrease power because you want tube distortion :)

Just installing smaller OT does not drop power until OT begin to saturate. Changing OT impedance change loadline angle and it effect power but without knowing operative voltages it is quessing how.

If you are after warm tube distortion you could test two very different power tubes and amp produce more 2nd harmonics already low power.

If you are after fierce 3nd (clipping) harmonics you could change OT impedance half and this make loadline steeper and max output power drop when loadline is not optimized and cant produce highest power and therefore distortion comes already lower power. Possibly bias should be lowered slightly as well so that tubes dont "redplate" but this can be test watching tubes when playing but if backplate must be removed to see tubes they should run bit cooler and when backplate is installed back they run hotter. I have read that old Fender amps function just fine when this is done and I think this is quite common user error which careless users have done and kept playing without knowing it.

Third way is to make power supply sag more. If amp use tube rectifier changing it less efficient can be test. This possibly require changing filter capacitor value smaller. Possibly you could find the same you have but very used rectifier asking around? Installint voltage dropper resistors to rectifier anodes is best way to increase sageffect and often not too difficult if tube socket has all eight pins and only four are used and resistors can be soldered to pins and feed wires are moved too.

None of these make amp as quiet and still sound "tube exhausted" as an attenuator will!
 
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printer2

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But who says that brownie is making 22W? And a half power drop is only going to drop you three dB. Will the new transformer drop power to 12W? What if it stops at 15W. Also when a transformer saturates will you like the sound? Also when the transformer saturates the inductance drops and it looks more like a short to the tubes.

Never realized it was a real Brown. If it were my amp I would put a PPIV master volume in the ext speaker jack and leave the rest of the amp alone.
 

schmee

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The small Princeton PT has a lot to do with the whole gambit for sure. I had a Vibrolux PT in a Princeton Rev until about a year ago, and although it was near the same voltages, it was amazing what it did for more headroom in the Princeton.

But it's also obvious how Fender designed their BF style amps from the Deluxe to the Twin, the significant difference being transformer size of the PT and OT.

A Princeton definitely becomes more of a gigging machine with a Deluxe OT and no other changes. I have no reason to believe it wont do the opposite with a Deluxe having a little Princeton OT.
 

guitback1

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Yes you can sub. You should rebias though. A tiny bit of "squish" in the brown cleanness may not be a bad thing.
But a PR tranny could work out for you, I just dont like you risking a vintage brown OT. A lot of vintage Deluxes run very high on plate voltage. Mine run 455-460!
I'm now using a simple "browner" for 115 VAC input.
That makes sense schmee, but not to worry there. I'm not going to use a true vintage OT. The idea is that I'd source an OT as close to a brown Princeton as I can get. My 6G3 is a clone in the first place -a good one, but still a clone nonetheless. While I do like the Mercury transformers, I'm trying to take that volume down a bit by subbing an output tran close to a brown Princeton.
 

guitback1

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But who says that brownie is making 22W? And a half power drop is only going to drop you three dB. Will the new transformer drop power to 12W? What if it stops at 15W. Also when a transformer saturates will you like the sound? Also when the transformer saturates the inductance drops and it looks more like a short to the tubes.

Never realized it was a real Brown. If it were my amp I would put a PPIV master volume in the ext speaker jack and leave the rest of the amp alone.
Printer2, you may be right. That really might be easier than switching out the OP tran in the first place. BTW, it isn't a real Brown Deluxe, but a clone. I had a real one back in the 90's that I foolishly traded for a Blackface Deluxe (no reverb). It worked for me at the time, because I needed clean in a small package. Little did I know things were going to be so cra cra with the prices of Brownies going up even more than other vintage Fender amps!
 

slider313

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Have you tried switching to a 5Y3 type rectifier, like the indirectly heated GE 6087, and re-biasing the amp?
 




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