So I have a triaxis

G

guidedbyechoes

Member
I bought a triaxis a few years ago because of clips I heard online. I got it, and it is noisy and flabby. Changed tubes and it got a little better. Got busy with other things and just tossed it in my closet. Decided to sell it and some one asked what version it is. It appears it is a V2 tx4 chip and recto vintage channel with the phat mod. Well I hate the " phat mod". I did some searching and the mod is actually the omission of some components. I have a vauge idea of what components it might be lacking, but I haven't been able to track down reliable schematics to verify what the non fat mod with the recto channel should include. As is it is the worst sounding preamp I've ever owned and it's supposed to be the best. Can anyone point me in the right direction? I feel bad dumping this device on someone else.
 
I have been using a Triaxis a lot 15 years ago. Bought it in 1995. It is not noisy, much less flabby. I had the phat mod removed at the time by a local tech. There's a good chance yours is kinda defective. I tried to use mine again some monthes ago after years in storage and I was greeted with flabby tone, crazy amount of noise (hiss especially lead 2 modes) and bleeding between channels etc. Not at all like I remembered. Turns out the yellow tantalum caps used in it have badly aged and all need to be replaced. It is currently being repaired by an electronician friend. Full schematic is not available online so it's not an easy task. I contacted Boogie and they have been friendly and helpful. They told me about the tantalum caps and gave me other pointers (they don't want to give the schematic though). We did what they suggested and it solved 80% of the problems I had with mine. Still not fully fonctional. Repair is ongoing. If you're in the US, I suggest you send yours to Boogie for a tune-up. They can remove the phat mod too. They still service the Triaxis and their fee is very reasonable if you're local, given the complexity of the task.
 
Jack Luminous":e6sdyxjw said:
I have been using a Triaxis a lot 15 years ago. Bought it in 1995. It is not noisy, much less flabby. I had the phat mod removed at the time by a local tech. There's a good chance yours is kinda defective. I tried to use mine again some monthes ago after years in storage and I was greeted with flabby tone, crazy amount of noise (hiss especially lead 2 modes) and bleeding between channels etc. Not at all like I remembered. Turns out the yellow tantalum caps used in it have badly aged and all need to be replaced. It is currently being repaired by an electronician friend. Full schematic is not available online so it's not an easy task. I contacted Boogie and they have been friendly and helpful. They told me about the tantalum caps and gave me other pointers (they don't want to give the schematic though). We did what they suggested and it solved 80% of the problems I had with mine. Still not fully fonctional. Repair is ongoing. If you're in the US, I suggest you send yours to Boogie for a tune-up. They can remove the phat mod too. They still service the Triaxis and their fee is very reasonable if you're local, given the complexity of the task.
Click to expand...

Yeah that's what I thought was happening. I have a similar type of friend and he looked it over, and there was nothing visually obvious that he could find with it. But it's hard to be sure without the schematics. From what I've red the phat mod is an omission of components, but I wanted to be sure which ones. I'm one the fence. The pre I have has never sounded good so I'm unsure if I even like it. I would hate to spend more money on it then hate it and have to sell it at a loss.
 
FWIW, I mentioned to a local amp tech that I was looking for a Triaxis and he gave me a look. I asked him what that meant and he said that they often (not always) do not age well. Lots of amps tht are even older use LDRs for switching (the Mark series among many others, like SLO) but they only use 3-5 or so. But he said there are a ton of them in the Triaxis and can be a cause for issues.

There are other guys here that use them or have recently and say they sound great, so even now they CAN sound good.

Hate to say it but you'll never really know until you play a properly functioning one and you won't feel comfy selling it as is. I'd just bite the bullet and send it to Mesa. Sometimes this gear thing is neither easy nor cheap
 
SpiderWars":366raoq6 said:
FWIW, I mentioned to a local amp tech that I was looking for a Triaxis and he gave me a look. I asked him what that meant and he said that they often (not always) do not age well. Lots of amps tht are even older use LDRs for switching (the Mark series among many others, like SLO) but they only use 3-5 or so. But he said there are a ton of them in the Triaxis and can be a cause for issues.

There are other guys here that use them or have recently and say they sound great, so even now they CAN sound good.

Hate to say it but you'll never really know until you play a properly functioning one and you won't feel comfy selling it as is. I'd just bite the bullet and send it to Mesa. Sometimes this gear thing is neither easy nor cheap
Click to expand...

That sucks. That's at least 300 there. If there is no other option it's just going back in my closet until I get more funds.
 
I removed the phat mod from my old tx4, took about an hour and a few parts. I found the diagram online on some forum, could have been this or the boogie forum. Made it 1000% better on lead 1 red channel. Still wish I had never sold it.
 
dpeterson":22k9dryp said:
I removed the phat mod from my old tx4, took about an hour and a few parts. I found the diagram online on some forum, could have been this or the boogie forum. Made it 1000% better on lead 1 red channel. Still wish I had never sold it.
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Lead 1 red is the vintage channel of a recto on mine. It's my favorite channel out of the whole pre as is. If it was a little tighter it would be even better. I'm not sure if the eq on that is pre or post gain. But the dynamic setting REALLY scoops it.
 
One other option would be strike a deal with a buyer such that you send it to Mesa, they go thru it and ship it to buyer. Not a very satisfying option but might be the least worst.
 
SpiderWars":27hjadtg said:
One other option would be strike a deal with a buyer such that you send it to Mesa, they go thru it and ship it to buyer. Not a very satisfying option but might be the least worst.
Click to expand...

I just heard some clips of how it was supposed to sound with the model I have. It sounds exactly like the sound I was trying to get out of my VHT. So I guess I will send it in at some point if I can't find schematics.
 
For whoever interested, here's the schem/doc I used years ago to remove the fat mod from my Triaxis. I believe it comes directly from Mesa. I just gave this to my local tech and he did the job flawlessly.


"Fat Mod" Reverse Modification Instructions

All mods are on the TX4 board (the Lead 1 Red board).
To reverse "Fat Mod" you’ll have to add 4 caps and 4 resistors and change 2 resistors.

1) Add 4 resistors:
R9 :120 KOhm
R44 : 33 KOhm
R45 : 330 KOhm
R46 : 82 KOhm

2) Add 4 disc. caps:
C5, C6 & C12 : 0.001 µF
C22 : 47 pF

3) Change these 2 resistors near the center of the board and labelled MID & BASS. Replace them with:
R33 (MID) : 1 MOhm
R34 (BASS) : 10 Kohm
 

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Jack Luminous":1535tkad said:
For whoever interested, here's the schem/doc I used years ago to remove the fat mod from my Triaxis. I believe it comes directly from Mesa. I just gave this to my local tech and he did the job flawlessly.


"Fat Mod" Reverse Modification Instructions

All mods are on the TX4 board (the Lead 1 Red board).
To reverse "Fat Mod" you’ll have to add 4 caps and 4 resistors and change 2 resistors.

1) Add 4 resistors:
R9 :120 KOhm
R44 : 33 KOhm
R45 : 330 KOhm
R46 : 82 KOhm

2) Add 4 disc. caps:
C5, C6 & C12 : 0.001 µF
C22 : 47 pF

3) Change these 2 resistors near the center of the board and labelled MID & BASS. Replace them with:
R33 (MID) : 1 MOhm
R34 (BASS) : 10 Kohm
Click to expand...

THANK YOU SOO MUCH!
 
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