Metal Ace Ultimatum mod

The definitive headphone guitar amp.
Ash517
Posts: 37
Joined: Mon Jul 31, 2017 6:14 pm

Metal Ace Ultimatum mod

Post by Ash517 »

https://www.facebook.com/groups/Rockman ... 590521604/

I’m wondering 2 things
1. How this mod sounds
2. If it works on the Guitar Ace

I’m no good at electronics, so I don’t wanna risk the life of my beloved Dunlop Guitar Ace. Anyone here know how removing that jumper affects things? Is it related to the compressor? The poster says it sounds less “choked-down” with the jumper removed, hence the compressor theory.
GEAR:
Rockman Guitar Ace (Dunlop)
Epiphone Les Paul Studio (Alpine White)
Boss Katana 100
Line 6 POD Go
RockmanCentralBob
Posts: 421
Joined: Fri Feb 06, 2015 2:10 am

Re: Metal Ace Ultimatum mod

Post by RockmanCentralBob »

I'm not on Facebook so I can't read it.
Ash517
Posts: 37
Joined: Mon Jul 31, 2017 6:14 pm

Re: Metal Ace Ultimatum mod

Post by Ash517 »

I’ve attached an image of the post with a circle around where the jumper-thinggy was.
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GEAR:
Rockman Guitar Ace (Dunlop)
Epiphone Les Paul Studio (Alpine White)
Boss Katana 100
Line 6 POD Go
RockmanCentralBob
Posts: 421
Joined: Fri Feb 06, 2015 2:10 am

Re: Metal Ace Ultimatum mod

Post by RockmanCentralBob »

Interesting.... I'll have to dig around to see if I have the schematics for the Metal Ace to see what's going on. Based on my understanding of the design of the Ultimatum, I highly doubt if it's doing the same thing. But, it could be that it sounds more like an Ultimatum that it did before the adjustments.

I will say that I take these "it sounds just like..." posts with a grain of salt. I'm guilty of it myself, but I've found that these comparisons are rarely made in an A/B comparison setting. And even then, it's a degree of comparison only.
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darthoverdrive
Posts: 64
Joined: Tue Mar 25, 2014 1:39 pm
Location: Kansas

Re: Metal Ace Ultimatum mod

Post by darthoverdrive »

I traced out a Guitar/Metal ACE a few years back, not sure if I posted the schematic on this site. I’ll dig it up if anyone is interested.

The trim pot and the jumper are for the compressor circuit. The trim adjusts the gain of the compressor opamp and removing the jumper removes the compressor from the feedback loop of the input circuit.

Removing the jumper won't hurt the amp but remember to put it back on the correct pins. Placing it on the opposite pins will greatly reduce the output volume.

If you going to adjust the trim pot I'd suggest measuring the ohms first, that way you can always try to get it back to the original setting.