Blackface Deluxe non-reverb servicing

Ronno25

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What do you guys think the $ value of this amp is? It has the original oxford speaker. Condition is not great but it's all there except for 5 knobs.
 

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Ten Over

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Would this hi pass filter reduce frequencies below the cutoff point while passing frequencies above the cutoff point? If so, then I can understand why one rarely sees this circuit in a Bf/SF Fender, neh???? New one for me…..I have an amp I need to open up for a look-see. Same non-verb circuit but built before this one was.
The second order high pass filter reduces the signal for frequencies below the cut-off point at the rate of 12dB per octave. The first order high pass filter reduces those frequencies at the rate of 6dB per octave. Theoretically. So at a couple of octaves below the cut-off point, the second order filter will reduce the signal way more than the first order filter even though both filters have the same cut-off point. It gives one the impression that the second order filter has a higher cut-off point when listening even though it doesn't.

There is no call for a second order filter in a guitar amp like this one.
 

slider313

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What do you guys think the $ value of this amp is? It has the original oxford speaker. Condition is not great but it's all there except for 5 knobs.

Probably in the $1,500-$1,800 range, as is.

This near mint one sold for $2,600 about 8 months ago.

 

David Barnett

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They look original to me:

Big blob of solder, soldered from the bottom and not touched since 1963, yep that's original as all heck. And odd.

Amp's probably an "MI" September '63, they did a LOT of Deluxe-Amps that month. The first real month of Blackface production. The extra network looks like maybe something Fender were playing with in the transition from Brownface to Blackface.

An AlNiCo speaker in one of these amps would be even more odd. Even the Brownface Deluxe-Amps had ceramic magnets. Mine had a big ol' whoppin' Oxford 12T6. I've seen two other "MI" Deluxe-Amps with that speaker, although the usual fitment was the 12K5.
 

Wally

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@Ronno25, what lower left coast wasking in an earlier post was IF you can use an ohmmeter to check for continuity between the 220k ohm resistors and the junction of those two ceramic caps in the tone circuit.
This would be done with the amp off, unplugged and preferably with the filter caps drained. If you are not familiar with putting an amp in a safe state, please do not work inside there.
 

Ten Over

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@Ronno25, what lower left coast wasking in an earlier post was IF you can use an ohmmeter to check for continuity between the 220k ohm resistors and the junction of those two ceramic caps in the tone circuit.
Check for a dead short. He might have a continuity mode on his DMM that will give us useless info.
 

Ten Over

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I can see the nub of an under board connector at the junction of the series capacitors. Both channels. I think there is a very high probability that this is the leg of the mysterious 220k resistor that was routed through the eyelet that is between the 100k resistors then under the board to the junction of the caps.
 

Ronno25

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Sorry if I'm misunderstanding. Is this what you're looking for?
 

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Wally

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I would love to hear this amp.…preferably up next to another BF guitar amp. The Normal channel of any of them compared to the Normal channel in this one would be interesting…especially if both amps were in the same operational condition with the same tubes and Biasing…through the same speaker.
 

Ronno25

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I would love to hear this amp.…preferably up next to another BF guitar amp. The Normal channel of any of them compared to the Normal channel in this one would be interesting…especially if both amps were in the same operational condition with the same tubes and Biasing…through the same speaker.
Unfortunately, I don't own any other blackface amps. Closest I have is a blackfaced sf twin reverb and some sf champs. I am familiar with how they sound though. If you were closer I'd bring it by!
 

David Barnett

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I would love to hear this amp.…preferably up next to another BF guitar amp. The Normal channel of any of them compared to the Normal channel in this one would be interesting…especially if both amps were in the same operational condition with the same tubes and Biasing…through the same speaker.

You and Ronno25 are welcome to come here and compare it to my AA763 "MI" Deluxe-Amp. :)
 

slider313

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An AlNiCo speaker in one of these amps would be even more odd. Even the Brownface Deluxe-Amps had ceramic magnets. Mine had a big ol' whoppin' Oxford 12T6. I've seen two other "MI" Deluxe-Amps with that speaker, although the usual fitment was the 12K5.
That alnico Oxford is not original to the amp.
 

Paul G.

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Could be a prototype? We'll never know.

BTW: I can fake those big bulbous solder joints from the top -- there's a technique.
 

schmee

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What do you guys think the $ value of this amp is? It has the original oxford speaker. Condition is not great but it's all there except for 5 knobs.
I dont think that is the original speaker, it should have an Oxford in it, ceramic not alnico.
My guess is it's worth $1500-1800 also, but could be worth more on a good day.
 

schmee

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I would love to hear this amp.…preferably up next to another BF guitar amp. The Normal channel of any of them compared to the Normal channel in this one would be interesting…especially if both amps were in the same operational condition with the same tubes and Biasing…through the same speaker.
Yes interesting, I used to play the normal channel on my DR quite often. I play the non reverb Deluxe a lot now, I think it's pretty similar, but just from memory, not able to AB them, as I sold the DR a couple years ago .
 

Robnik33

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If you want to do a next level restoration, put new capacitors inside the existing shells

Look up "how-to-restore-vintage-astron-minimite-electrolytic-capacitors" on the Hardway Vintage Electronics site. It won't let me link directly.

1662430981453.png
 




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