Some thoughts on the Triaxis and tube selection......

[disassembled]

Hey everyone, I know Timbre Wolf has posted about this extensively and has nearly talked about the topic to death but I am going to take a different approach since I don't have any NOS tubes to use at the moment. Recently I have been thinking of getting rid of my TA and 20/20 for a Mark IV head because of the straight forwardness, simulclass, less compressed preamp, reverb, and plus everyone's posts are either for the TA or against it the latter being the majority. The negatives are: shared controls on RHY and RHY2, the weight (my rack weighs about 30 lbs and is 40 watts, plenty for me), I am living in Japan so I can't go to the local store to try a Mark IV.

So I was thinking: How can I make the TA less compressed? First of all, I don't use much gain as it covers up my sloppy playing and adds a lot of compression which kills the dynamics I want. There are 5 preamp tubes and 2 of them are used all of time with the other three being for the actual tone and gain of the preamp. V1, V2, and V4 are the preamp tubes i concerned myself with since these are going to alter the tone and gain in the biggest ways. Changing out V3 and V5 might alter the tone but it wouldn't be as drastic as the others. I have a few tubes to mess with here: JJ ECC81(12AT7), JJECC83S, JJECC832(12DW7, this tube is half 12AX7 and half 12AU7), various Mesa labeled tubes, Sovteks, EH, and unlabled chinese tubes. Nothing exotic or fancy here just tubes produced in the last 10 years or so. The only thing I am going to do is mess with the tubes doing any circuit modifications is going too far for something that I can find in another amp.

I was trying to concentrate on LD2 tones as they are great sounding but sound a little too compressed with the gain high but too thin with the gain low. My solution? Reduce the gain with lower gain tubes and run the gain controls higher. How did I do this? I put two JJ ECC832 tubes in V2 and V4. This reduces the gain A LOT(probably close to half). To get a heavy tone I have to run the Gain and Drive close to 10 but I don't even want to use that much drive. In the LD2 green i ran the gain at 6 and the drive at 7.5 and I get great dynamics. I am talking like: soft picking makes the amp sound like a clean channel that's pushed while strumming leads to a very aggressive biting tone. Before I could achieve this but the gain had to be dialed in much lower and therefore the tone was a bit thinner. It is really hard to A/B this setup because the settings MUST change due to the characteristics of the tubes.

I also wanted to apply this to the LD1Red channel that is always over the top and has that super compressed feel unless you run the gain really low (which again thins out the tone). I place a ECC81 in V1 and am pretty happy with the results because I can run the gain a bit higher to get a fuller tone without having too much drive to retain the dynamics.

I will try to find a way to post clips later (they will not be good as far as playing goes but I think the tone will be neat to A/B). I am not saying this sounds like the amps these modes are trying to emulate but the gain reduction helps my ears enjoy the tone and touch responsiveness more.

If you are using the TA and find you are dialing the gain way down (less than 5 i guess) you might benefit from a tube swap like. I figure most users are not using the TA for anything but high gain distortion so this probably won't apply to most. I just like having the option of whether the preamp sounds compressed or not. It may still really sound compressed I won't really be able to tell until I A/B the two setups.

Greg

 

[chedgeco]

Greg,

Thank you for sharing your research. I too am one of those TA non high gain users.

I've had the original tubes in my TA since I got it from Tim up at Boogie about 5 years ago. He said it had those sweet 80's chinese preamp tubes in it. I've never even taken them out because I can get what I need out of it so I'm not even sure what's in there.

But as I get older I notice the gain going down so your information could prove to be very helpful.

Chris... 8)

 

[lockbody]

When I had my TA, I liked subbing in JAN-Phillips 12ax7, at7, and 5751. Probably not as good sounding as other NOS tubes, but a definite improvement over any Mesa or Sovtek I tried before.

Those JAN-Phillips are still available at decent prices.

 

[JAZZGEAR]

Funny thing I keep hearing about the TA being too compressed, but have you played it with a 6L6 amp, aka 2:90?

I currently have (and have had in the past) the 20/20 with my TA -- as I noticed from your sig you do too. Then you must know that alot of that compressed sound is coming those EL84s -- it's there nature to compress.

I never noticed my TA being too compressed in any mode when I used it with my 2:90....in fact, it never compressed, unless it got to a ridiculously loud volume -- which only happened once or twice outdoors.

Maybe you need to look at the power amp you are using in addition to the tube experimentation with your TA.

....although it will be pretty hard to go to a 6L6 rack amp w/o adding substantial weight, the #1 why I finally caved in and sold my 2:90 and went back to the 20/20.

 

[disassembled]

The only amp I have used with the TA is the 20/20 (which has the mid boost removed so it is less in your face and a more balanced tone). Upgrading power amps would probably lead me to go for a MK 4 instead. At this current moment I am not playing out or with a band so my tonal impressions are coming from low to moderate practice volumes. Being that I live in an apartment/dorm setup I can't turn the amp up to get it into clipping(another reason why I want to stick with the low wattage amp). I was just wanting a more open breathing type feel and I might be closer now than I was before. Ideally I want the PA to do most of the distortion or crunch where the preamp is just there to push it to that point. This leaves me with a dynamic preamp that can do the clean/clip thing by picking hard or soft.

The bad thing about my situation is I can't try before I buy. The japanese music stores stock a lot but they go for the popular stuff like: marshalls, rectos, F series, etc because there isn't much room to keep many items in stock. I would get it shipped from the US anyway and probably buy used if I did anything. But I am eyeing up an old Mark series 212 cab here that I want and may replace my Peavey vert 212 from the same era.

I have only had the TA for a short time(since Sept or so) and I can't use it with a band yet so my opinions are not backed strongly. Maybe these changes would go unnoticed in a band situation and may be preffered for the stock config. I would hope that I could replicate these changes with different settings but I have not spent the time trying (i need more practice than better tone at this point). It's just a quick fix for right now. It does take away a lot of gain so I think many people will not have any desire to even try it.

When I do my retube this year I am going to go through Doug instead of Bob to get some tonal variation out of the my tubes (I run mostly JJ and have for years) because I heard the Tung Sol reissue is supposed to be a decent tube as well as the new chinese ones.

 

[Timbre Wolf]

Hey Greg - two brief notes:

- I've found that V3 actually does greatly influence the compression of the amp, and would recommend you try a 5751 or 12AT7 there, find out if you like it.

- The tonal emphasis changes as you go from low gain to high gain settings (from brighter to more middy, respectively), so its important to account for that as you change gain with tube swaps, and compensate by raising the presets' gain settings.

Oh yeah, and you might find that you like some tubes more than others. YMMV!

- Thom 8)