Make an original Blackface Deluxe better?

[MrCoolGuy]

My apologies. So, he likes the Normal channel over the Vib channel, correct? So, he likes the gain that is in the Normal versus the loss of gain due to the tremolo in the Vib Ch. Has he played through a BFDR? Or a SFDR…..through the Vib channel.…or any BF/SF reverb amp? He may be looking for that richness that comes with the little bit of extra gain????
ime, a player who won’t play their guitar through their amp in front of a tech while seeking what they want but don’t hear is impeding possible progress.

I agree, but it's not him... he probably would play in front of me if I asked...
I've just been super busy. It's baseball season and I coach two teams. But I am going to try to get him over. He has a 65 Twin Reverb (it was with the Deluxe, literally in the and barn. I fixed it too. He used it for big/outdoor shows - what pics I could find attached-), and a Deluxe Reverb RI.
He said that he prefers the Nor channel on this amp because the vib channel is too bright. He plays a strat. But, to me, the vib channel sounds fantastic.

 

[cobaltu]

The sound you hear when listening to the recording is after the amp is miked and then engineered further to create the track, and then there is additional mixing and mastering.

I feel like this is commonly the problem. We don't really like the sound of electric guitar amps in person, we like the sound of them on recordings.

 

[cobaltu]

To answer the OP, I would:

1) Change the V2b to ~4.7uF. This will trim off a bit of the unnecessary sub-bass, and make the amp more focused and tighter.

2) If more trimming is needed, change the coupling caps b/w the PI and power tubes to 0.047-0.022uF. Basically the same effect as before but just more HPF.

Trimming bass in the Fender reverb amps is hard. They don't have too many coupling caps b/w stages that make enough of a difference. And in some places it's not a good idea because it affects the mixing of the dry/reverb signal.

 

[Twang Deluxe]

Wow!!! Amazing amp. Leave it as it is and use an EQ-Pedal

 

[Trenchant63]

A while back, a working local musician brought me an original '64 blackface Deluxe (non-reverb). It was in terrible physical condition, but it was almost all original.
I cleaned it up, installed new E. Caps,
3-prong cord, etc. All the voltages are where they should be. I got everything working as it should and gave it back to him. He was very happy with it and it's been his main amp for indoor venues ever since.
But he thinks it could be better. He's thinks the vib channel is too bright, so he's been using the nor channel. He wants me to remove the bright cap from the vib channel and he wants the bass tightened up a little. I was thinking of just upping the first filter stage capacitance a bit, but I'm curious what you guys think.
And I know the easy answer is to tell him that maybe it's not the amp he wants...
But apparently, this amp is as close to being perfect for him as any amp he's played, just wants to dial it in.
Also, right now it has a 5U4GB rec tube.
I know this can change the feel of the amp, but it puts the voltage closer to what it's supposed to be. How much capacitance can that 5U4GB handle?
Some charts say 20uf max, some say 40uf max...
Thoughts?

Also, he sent his as an example of what tone her likes...Can't Hide a Heartache:

Here's a couple pics from when I first got it. Yes, that's a dirt dauber nest... lol
View attachment 1099667 View attachment 1099668

I was trying to listen to the guitar tone when the steel guitar sound took over my ears - what a gorgeous sound! Back to your point (I’m not an amp tech) - sounds like he might be asking for a bit beyond what the DR is designed to do? I’ve never associated DRs with tight bass - at least the ones I’ve played. I always thought because of the tube rec and the shallow cab depth/open back, that the bass is a bit softer and fat vs tight and punchy.

 

[Engine Swap]

My guess is he’s missing the reverb. Does he have a pedal?

 

[NTC]

I was trying to listen to the guitar tone when the steel guitar sound took over my ears - what a gorgeous sound! Back to your point (I’m not an amp tech) - sounds like he might be asking for a bit beyond what the DR is designed to do? I’ve never associated DRs with tight bass - at least the ones I’ve played. I always thought because of the tube rec and the shallow cab depth/open back, that the bass is a bit softer and fat vs tight and punchy.

It is not a DR, it is a D non-R. Similar but different animal.

 

[Pete Farrington]

He said that he prefers the Nor channel on this amp because the vib channel is too bright

With non verb models, the normal channel also has a touch more gain, about 4-5dB. And a touch more gain almost always gets perceived as better.

change the coupling caps b/w the PI and power tubes to 0.047-0.022uF

Yes, I suggest that as a default, as it’s pretty much entirely beneficial, no downsides. By definition it’ll at least halve bias excursion time, reducing the tendency to flubby breakup. And with non master volume designs, the output valve grids are almost always where, as signal level rises, overdrive will occur first and the depth of overdrive will be greatest.

 

[MrCoolGuy]

With non verb models, the normal channel also has a touch more gain, about 4-5dB. And a touch more gain almost always gets perceived as better.

Yes, I suggest that as a default, as it’s pretty much entirely beneficial, no downsides. By definition it’ll at least halve bias excursion time, reducing the tendency to flubby breakup. And with non master volume designs, the output valve grids are almost always where, as signal level rises, overdrive will occur first and the depth of overdrive will be greatest.

Why would the Normal channel have more gain? I thought the Vib channel gained a little from the trem circuit
..

 

[MrCoolGuy]

With non verb models, the normal channel also has a touch more gain, about 4-5dB. And a touch more gain almost always gets perceived as better.

Yes, I suggest that as a default, as it’s pretty much entirely beneficial, no downsides. By definition it’ll at least halve bias excursion time, reducing the tendency to flubby breakup. And with non master volume designs, the output valve grids are almost always where, as signal level rises, overdrive will occur first and the depth of overdrive will be greatest.

Why would the Normal channel have more gain? I thought the Vib channel gained a little from the trem circuit.

 

[Phrygian77]

Why would the Normal channel have more gain? I thought the Vib channel gained a little from the trem circuit
..

It's the opposite. The 50k intensity pot puts a heavy load on the output of the second gain stage. The amps with reverb make up for that with an extra gain stage.

 

[MrCoolGuy]

It's the opposite. The 50k intensity pot puts a heavy load on the output of the second gain stage. The amps with reverb make up for that with an extra gain stage.

I see. Thank you. I didn't know that.

 

[schmee]

Listening to the track provided that the amp owner likes, I think the tone on that track is more about using a Tele and maybe a compressor than about the amp.

 

[Telenator]

This one is easy. Make it a mid 70's silverware spec amp. Much smoother.

 

[MrCoolGuy]

And for the record, on that Kilgore track, he was referring to the solo at 1:20... not the pedal steel...

I should have cleared that up.

 

[Lowerleftcoast]

The bass frequencies of the guitar on that track seem to fall off a bit. That is pretty much what I expect from *this circuit* and the V30 speaker. Usually to stay out of the way of the bass player, bass energy from a guitar is not desired. (I know, I know, some CW tele style leads maintain a lot of bass frequencies.)

In light of the guitarist's request, I don't see any reason to keep the Vibrato channel treble cap.

I am curious how he is liking the GA SC64. I am also curious if it is *broken in* yet. As you know, a *broken in* speaker will have different bottom and top end frequencies.

My gut tells me to start with the stock circuit and change things to suit his liking. Since he seems to like what he is hearing with the voltage drop of the rectifier, I am hesitant to go back to a GZ34. Your interpretation of what the owner wants seems like it might be accomplished with some tube rolling and maybe a speaker swap if the GA SC64 doesn't work for him.

After that...
To reduce highs a little more, place a 500pF to 1000pF cap parallel to the V2a plate resistor.

To help the bass, idk. The 5R4 might not like the 16uF reservoir cap that is in there now, so, imo, going higher is not an option. (It might be a good idea to place protection diodes in front of the tube rectifier.)
You could try a 2.2uF - 4.7uF cathode bypass cap on V2a. This would get rid of some subs, so it might clean up the bass he is hearing.
A costlier mod would be to change the OT. I would change from the 6.6k primary to a 8k primary. Try a Hammond 1750PA or a Hot Rod Deluxe OT configured for ~8k primary. I think both of those transformers are physically larger than a deluxe OT so some modifications will have to be made to make them fit. If I am interpreting correctly, it seems he is liking a woollier sound with the lower B+. An OT with 8k primary will take it further towards woolly.

He might like it to compress more. Changing the 470R 6V6 screen resistors to ~1k would result in a little more compression.

 

[David Barnett]

And I think I'm going to have to try to pull some more info out of the owner...
He said it doesn't have too much bass...
Just that the low end is "missing something" and isn't as "pretty" as the recording he referred to. Lol

An amp in a room will never sound like a recording.

 

[MrCoolGuy]

The bass frequencies of the guitar on that track seem to fall off a bit. That is pretty much what I expect from *this circuit* and the V30 speaker. Usually to stay out of the way of the bass player, bass energy from a guitar is not desired. (I know, I know, some CW tele style leads maintain a lot of bass frequencies.)

In light of the guitarist's request, I don't see any reason to keep the Vibrato channel treble cap.

I am curious how he is liking the GA SC64. I am also curious if it is *broken in* yet. As you know, a *broken in* speaker will have different bottom and top end frequencies.

My gut tells me to start with the stock circuit and change things to suit his liking. Since he seems to like what he is hearing with the voltage drop of the rectifier, I am hesitant to go back to a GZ34. Your interpretation of what the owner wants seems like it might be accomplished with some tube rolling and maybe a speaker swap if the GA SC64 doesn't work for him.

After that...
To reduce highs a little more, place a 500pF to 1000pF cap parallel to the V2a plate resistor.

To help the bass, idk. The 5R4 might not like the 16uF reservoir cap that is in there now, so, imo, going higher is not an option. (It might be a good idea to place protection diodes in front of the tube rectifier.)
You could try a 2.2uF - 4.7uF cathode bypass cap on V2a. This would get rid of some subs, so it might clean up the bass he is hearing.
A costlier mod would be to change the OT. I would change from the 6.6k primary to a 8k primary. Try a Hammond 1750PA or a Hot Rod Deluxe OT configured for ~8k primary. I think both of those transformers are physically larger than a deluxe OT so some modifications will have to be made to make them fit. If I am interpreting correctly, it seems he is liking a woollier sound with the lower B+. An OT with 8k primary will take it further towards woolly.

He might like it to compress more. Changing the 470R 6V6 screen resistors to ~1k would result in a little more compression.

I hear ya, @Lowerleftcoast, but it wasn't a V30, it was a V Type. He said he likes the Alessandro much better. And, yes, it is broken in. Very well broken in. After talking to him, apparently the GZ34 burned up... that's when he put in the 5R4.

In a stunning turn of events, lol,
I was playing and listening to the machine today and it got nasty... then lost volume.
I quickly figured out that the power tubes are bad. So I asked him in a condescending voice... had it been losing power while you're playing? "Yeah, it'll just fall right out, then the bass sounds ugly"...
SMH... Was this his problem the whole time?
I put in a WZ34 copper cap I had laying around, (I use that thing a lot working on amps), some good tubes, rebiased.... sounds amazing! Here's gonna come play it with me to see how it sounds, but I can't imagine him not liking it.
It is interesting, though, that these tubes were working intermittently... and seem fine between crashes... hopefully something else isn't causing this.

 

[Pete Farrington]

I put in a WZ34 copper cap

At full load current, those things sag far more than a decent GZ34.

 

[MrCoolGuy]

At full load current, those things sag far more than a decent GZ34.

Yeah, just temporary. I didn't have another gz34 laying around. Ordered him a proper tube.