Burr Brown

[leadfootdriver]

http://www.futurlec.com/index.shtml

Op Amp:
OPA2134PA


8 pin socket:
ICS8

I'll post back when I actually receive this stuff just to make sure everything is on the up and up, I placed the order 3weeks ago:?

Thanks! I've searched about the op2134 all day, and it seems to be a good piece.

 

[disassembled]

I used Mouser electronics and they shipped right away. I suggest going with mouser or allied electronics.


Greg

 

[leadfootdriver]

Has anyone tried the OPA2604?

 

[Martin]

You took the words right out of my mouth. I have used 2604's in the past but in Hi-Fi aplications not in guitar amps. They sound great, I would be very interested to see if anyone has tried on in their Triaxis.... might be worth a couple of dollars to check it out.

 

[leadfootdriver]

You took the words right out of my mouth. I have used 2604's in the past but in Hi-Fi aplications not in guitar amps. They sound great, I would be very interested to see if anyone has tried on in their Triaxis.... might be worth a couple of dollars to check it out.

I researched the OPA2134, and in a lot of cases the OPA2604 came up along with higher praise. It's reputed to have better sound quality and even higher dynamics, but it's not a direct drop in from what I've read.

I read that the higher slew rate could cause oscilation, and it has a much higher current draw. So with the higher power, the more heat it will generate. Plus, I don't know how it will affect other parts in the circuit, and if this will cause a chain meltdown. I feel confident in replacing a TL072 with an OPA2134 as the DIY community accepts that this is a safe swap.

I don't know much about electronic, so I hope some of you people with the knowledge and the tools will test it out because I ordered a couple along with a few OPA2134's just in case! :lol:

I cracked open my ART Digital MPA GOLD, and it had 4-OPA2134's. So I'll just leave that alone. My crappy little Crate V58 amp has a TL072, so i'll be yanking that out with a quickness! I'll put the OPA2604 in there to see how it does because the total parts in that amp would only run me $20 if I melt it!

 

[Martin]

All I can say is that I have swapped them for replacements for op427's and the 5334's I think it was, anyhow... I have never had them cause a problem but like you say it may be dependant on other components in the circuit.

 

[leadfootdriver]

All I can say is that I have swapped them for replacements for op427's and the 5334's I think it was, anyhow... I have never had them cause a problem but like you say it may be dependant on other components in the circuit.

Yeah mang, I'm excited either way. How are you liking you OPA2134 swap so far? How did it affect the sound"? Did it make it any warmer or smoother?

Here's a couple of notable links I saved in my favorites that you could glance throug if you had the time.

http://www.icixsound.com/vb/archive/index.php/t-637

This one is a bit long winded, but I linked the article at the end where he picked out the OPA2604 clearly against the OPA2134. Scroll down and read the summary under the sound file pics.

http://www.sixmoons.com/audioreviews/kingrex2/u_2.html

 

[RobertH]

I'm still waiting on my delivery :roll: I would caution people to not go too far from the TL072, with limited knowledge of the circuit, things may get a little "scary" :shock:

 

[Martin]

I haven't had much time to play around with my pre-amp ironicaly but I have five songs to learn tonight so I'll let you know how that goes !

 

[leadfootdriver]

I'm still waiting on my delivery :roll: I would caution people to not go too far from the TL072, with limited knowledge of the circuit, things may get a little "scary" :shock:

I ordered from mouser. Mine will be here in 2 more days. :wink:

 

[RobertH]

I did too, the place I was dealing with had their heads up their ***** :x

 

[leadfootdriver]

I did too, the place I was dealing with had their heads up their ***** :x

I ordered online, and it's comming from Texas.

 

[disassembled]

Mouser is absolutely wonderful for quick shipping and getting the right parts out to you.


I hope everyone that does the mod enjoys it.

Greg

 

[leadfootdriver]

I bought a box of sockets from the local electronics store and installed 1 in the IC3 tonight.

My shipment is on schedule, and will arrive tomarrow. All I'll need to do is push one in the socket and play! :wink:

 

[leadfootdriver]

:evil: I just socketed my little Crate V58 which had a TL072 as well. That opamp and the one in the TriAxis were both from Texas Instruments. BUT the one in the Tri was made in Mexico, and compared to the Crate opamp, it sounded like harsh ass! :evil: It was buzzy and hard sounding; too thin and bright. The other opamp sounded full and warm; not buzzy.

I've been playing 9 years with a ****** opamp in my TriAxis. I can't wait tomarrow to get the new part. It should be a world of difference. :!:

 

[leadfootdriver]

Did the OPA2134 install. 'Been playing it for a while. You immediately notice a smoother, fuller sound when you first listen to it. It's not a hard sound like the TL072, which is what always stood out to me the more I dialed in the Dynamic Voice. That's gone now.

I tried out an OPA2604 as well. It had a significantly more lowend output compared to the OPA2134 which had more bass then the TL072! It almost had a tube overdrive sound to it although it did NOT clip on the clean tones.

 

[Martin]

I have been living with the new op amp for over a week now and have to say it is definately better all the way round. You not only notice a difference in the tonal delivery but also the feel is different.

It's a hard thing to describe but lead tones to me at least, feel better, less compressed somehow I think, more fluid.

The highend is also way less piercing. Anyone else notice this ?

 

[leadfootdriver]

Yup. The tone is more filled out and rich. I put the opa2604 back in there. It's a little warmer and more dynamic then the opa2134. I thought I was having an oscilation problem with the 2604, but I was wrong.

Have you noticed that the clairity has changed the longer you play it? I guess they "break in" after a while.

 

[Martin]

Yes, the tone will definately get better after playing it a while. If you have a looper you could play a phrase at low volume overnight and it would sound much better in the morning.
I used to do upgrades to high end CD players for people using the very same opamps. another thing you could do (but there's no space) is power the opamp independantly with it's own supply by bending the +/- supply pins away from the socket and build a small linear supply, this would allow it to draw power independantly, devolved from the main board and again would sound better.
I used to do this as well as run them in class A by connecting a resistor between two of the pins but I forget which ones as all my notes are back in Scotland.

The bridge rectifier on the Triaxis could be swapped out for high speed shottky diodes, again this yeild a surprising difference is sound quality.

There is a few obvious mods that could be done to this unit, the only problem is lack of space.

I just ordered an OPA2604 to try one !! will let you know how it turns out !

 

[leadfootdriver]

Yes, the tone will definately get better after playing it a while. If you have a looper you could play a phrase at low volume overnight and it would sound much better in the morning.
I used to do upgrades to high end CD players for people using the very same opamps. another thing you could do (but there's no space) is power the opamp independantly with it's own supply by bending the +/- supply pins away from the socket and build a small linear supply, this would allow it to draw power independantly, devolved from the main board and again would sound better.
I used to do this as well as run them in class A by connecting a resistor between two of the pins but I forget which ones as all my notes are back in Scotland.

The bridge rectifier on the Triaxis could be swapped out for high speed shottky diodes, again this yeild a surprising difference is sound quality.

There is a few obvious mods that could be done to this unit, the only problem is lack of space.

Cool! What do you think about a Brown Dog adapter http://www.cimarrontechnology.com/index.asp?PageAction=VIEWPROD&ProdID=9

And putting 2-opa627's?

Tell me more about the rectifier mod!