Ace Tone 601 power supply

[vaughandy]

Hi folks,

I'm hoping someone with a bit more knowledge of power supplies for tube amps might be able to give me some insight. I recently acquired an Ace Tone Model 601, all tube amp head. I'm pretty excited to get this thing up and running, as it seems like it's gonna be pretty badass. Check it out:

1969 Ace Tone Model 601 50w Tube Head | Flickr - Photo Sharing!

So, this was apparently wired for use in Europe, as it had a 220V power supply. The guy who I got this from was going to replace it with something more conducive to US 120 v, but aside from removing the power cable and probably something else it was connected to, he never got around to replacing it.

So at this point, I have this amp with everything else ready to go but no way to plug it in. It looks like the original transformer is still there, I just don't really know how to hook it up to AC, or whether I even can, or whether I need to get a new transformer.

I've posted a picture of part of the schematic with the power supply and transformer. If anyone has any advice, I would be forever grateful.

[olddawg]

Hi folks,

I'm hoping someone with a bit more knowledge of power supplies for tube amps might be able to give me some insight. I recently acquired an Ace Tone Model 601, all tube amp head. I'm pretty excited to get this thing up and running, as it seems like it's gonna be pretty badass. Check it out:

1969 Ace Tone Model 601 50w Tube Head | Flickr - Photo Sharing!

So, this was apparently wired for use in Europe, as it had a 220V power supply. The guy who I got this from was going to replace it with something more conducive to US 120 v, but aside from removing the power cable and probably something else it was connected to, he never got around to replacing it.

So at this point, I have this amp with everything else ready to go but no way to plug it in. It looks like the original transformer is still there, I just don't really know how to hook it up to AC, or whether I even can, or whether I need to get a new transformer.

I've posted a picture of part of the schematic with the power supply and transformer. If anyone has any advice, I would be forever grateful. [ATTACH=CONFIG]12624[/ATTACH]

So you posted everything but a shot of the back of the amp! Does it actually say 220/240v on it? The schematic doesn't specify the primary voltage. This power supply has a voltage doubler circuit on the B+. The PT itself seems to have two 6.3v filament taps, a 15v bias tap, and a 175v B+ tap. The doubler circuit would bring the B+ closer to 350v. If I was messing with this amp I would be tempted to choose a different PT and get rid of the doubler, but this amp has some old PCBs and may be a bitch to modify. You could always get an external step up transformer to power it. In that case remove the ground reverse switch and the death cap, connect the primary high and low sides to the power cord, and ground the earth wire to the chassis. BTW, if you are not experienced with working on tube amps this will not be an easy process and you could hurt yourself if you don't know the basic skills. Once you get the power supply up you will probably have a bunch of bad electrolytic capacitors.

[vaughandy]

So you posted everything but a shot of the back of the amp! Does it actually say 220/240v on it? The schematic doesn't specify the primary voltage. This power supply has a voltage doubler circuit on the B+. The PT itself seems to have two 6.3v filament taps, a 15v bias tap, and a 175v B+ tap. The doubler circuit would bring the B+ closer to 350v. If I was messing with this amp I would be tempted to choose a different PT and get rid of the doubler, but this amp has some old PCBs and may be a bitch to modify. You could always get an external step up transformer to power it. In that case remove the ground reverse switch and the death cap, connect the primary high and low sides to the power cord, and ground the earth wire to the chassis. BTW, if you are not experienced with working on tube amps this will not be an easy process and you could hurt yourself if you don't know the basic skills. Once you get the power supply up you will probably have a bunch of bad electrolytic capacitors.

Someone else suggested the external transformer and I think that's the way to go. Unfortunately, I have no idea which of the leads coming from the transformer are which. Anyone have any suggestions for this?

I appreciate the warnings, and am somewhat of a novice at this sort of thing. However, I am very careful about working with high voltages and always make sure to discharge any caps.

[vaughandy]

I wonder if there's some way of measuring resistance with a multimeter between the various leads to figure out which windings are which...

[Jazz P Bass]

Quote"I appreciate the warnings, and am somewhat of a novice at this sort of thing. However, I am very careful about working with high voltages and always make sure to discharge any caps."
We are dealing with the primary of the transformer which you are attempting to hook up to the mains voltage.
The capacitors are on the secondary.
You really should take this to a tech.

[vaughandy]

Quote"I appreciate the warnings, and am somewhat of a novice at this sort of thing. However, I am very careful about working with high voltages and always make sure to discharge any caps."
We are dealing with the primary of the transformer which you are attempting to hook up to the mains voltage.
The capacitors are on the secondary.
You really should take this to a tech.

Yeah, I aware of that. I was just anticipating someone reading me the riot act. Obviously I'm not charging up any capacitors as the transformer isn't connected to anything.

I'm not just blindly attaching this thing to ac power and touching my multimeter to various leads. My plan is to use a much lower voltage AC source to test the secondaries once I've determined the primaries. Unfortunately there are 4 leads on the primary side, so even figuring that out isn't a no-brainer.

[vaughandy]

very low volume, scratchy output,flickering standby light on old tube amp

hey dudes,

So I'm making progress! I'm now able to get some, albeit shitty, sound from it.

Here's the deal: I can only get very low volume, intermittent sound. Does this sound like a manifestation of bad tubes, bad caps, or...? I'm sure I'll need to replace the caps as they're original from 1969, but I guess I'm curious if this sort of thing is something one would expect bad caps to manifest as. I **think** all the tubes I'm using are in working order, but I haven't exhaustively determined that.

Also of note is that the standby light is behaving strangely... it flickers, and occasionally turns completely off and then back on. I've read somewhere that this could just be an old resistor on that light, but I wonder if it could be a manifestation of something more. Also very much of note is that I'm only able to get ~160V out of my power transformer to a circuit (most of which goes to the speaker transformer I believe) that is supposed to see 175V. Is that voltage deficit enough to be a major culprit? Any experience with that sort of thing?

Any ideas would be very much appreciated!!!

1969 Ace Tone Model 601 50w Tube Head | Flickr - Photo Sharing!

[Udonitron]

I have a 601
There is a switch on the inside left side chassis that allows you to switch from 100v to 117v
I need to rebuild mine...bought it without tubes etc.
I will follow this thread for sure...did you rewire for 6L6's or kept the 7591's?

Notice the lower left corner of the photo

[vaughandy]

unfortunately mine had no such switch, as it originally had a 220V primary power transformer. They must have made two versions, one for US power and one for euro / japan power. I ultimately got a great power transformer from Edcor that works perfectly for me.

I kept the original 6L6 tubes, and they sound killer! My only complaint with the amp at this point is that it's still pretty noisy. I think the reverb circuit might be the culprit, so I'll be looking into that.

Is your amp currently working? If so, do you hear a noticeable difference between channel 1 and channel 2? For whatever reason, channel 1 overdrives for me way earlier than channel 2. I can't really figure out what up with that. Does yours do the same?

I have a 601
There is a switch on the inside left side chassis that allows you to switch from 100v to 117v
I need to rebuild mine...bought it without tubes etc.
I will follow this thread for sure...did you rewire for 6L6's or kept the 7591's?

Notice the lower left corner of the photo

[Udonitron]

Ah the Euro version, cool!
It should have come with 7591's power tubes, yours might have been swapped out at some point.
The 7591's are amazing but loads of headroom so little tube distortion but take pedals well.

Mine has yet to be heard lol
Learning slowly about tube amps and thus I have 2 Guyatone's, a Teisco, and 2 Ace Tone's to repair...the Ace Tone Duetto should arrive on Friday

[vaughandy]

oops, yeah, replied to quickly. I do use the original 7591s. I got an extra pair with the amp as well, both pairs sound nice.

Ah the Euro version, cool!
It should have come with 7591's power tubes, yours might have been swapped out at some point.
The 7591's are amazing but loads of headroom so little tube distortion but take pedals well.

Mine has yet to be heard lol
Learning slowly about tube amps and thus I have 2 Guyatone's, a Teisco, and 2 Ace Tone's to repair...the Ace Tone Duetto should arrive on Friday