I've recently started building my own gear and have discovered the diversity of op amps. I am currently wanting to upgrade the TL072's in my Crate head.
It uses 5 and I was wanting something much higher end but I'm not satisfied with the specs of the chips people are recommending me.
The TL072 has a typical slew rate of
16 V/uS and the AD825 I was considering is 140 V/uS ! The gain bandwidth difference is about the same. Can anyone tell me if the AD825 is a good idea and if not feel free to make suggsetions.
I'm not really interested in the NE5532 or NE5534 which seems to be the popular ones guys swap the TL072's out for.
It uses 5 and I was wanting something much higher end but I'm not satisfied with the specs of the chips people are recommending me.
The TL072 has a typical slew rate of
16 V/uS and the AD825 I was considering is 140 V/uS ! The gain bandwidth difference is about the same. Can anyone tell me if the AD825 is a good idea and if not feel free to make suggsetions.
I'm not really interested in the NE5532 or NE5534 which seems to be the popular ones guys swap the TL072's out for.
Really, you should swap out the opamps for a tube preamp stage, if you ask me.
I think you will have to experiment to find the tone you want. I would think that the experimentation in musical instruments (yes, an amp is as much an instrument as anything else) should be the quest for tone/colour, instead of hifi where we seek to eliminate colour as far as possible. Therefore the same methodology may or may not be beneficial.
Of course, the NE 5532 is a slight upgrade and the ones you are quoting seem even better but you should actually hear the sound for yourself. It is possible that you may actually like the sound of a 'lower end' chip a little more.
Best is to buy as many different types as you want and decide on which one (or combination) you want.
I think you will have to experiment to find the tone you want. I would think that the experimentation in musical instruments (yes, an amp is as much an instrument as anything else) should be the quest for tone/colour, instead of hifi where we seek to eliminate colour as far as possible. Therefore the same methodology may or may not be beneficial.
Of course, the NE 5532 is a slight upgrade and the ones you are quoting seem even better but you should actually hear the sound for yourself. It is possible that you may actually like the sound of a 'lower end' chip a little more.
Best is to buy as many different types as you want and decide on which one (or combination) you want.
OPA2134 - good replacement for TL072
I've built some stuff using TL072, since they are very cheap. After
finishing my project, I replaced the TL072 witch OPA2134's and
the sound definitely improved. BTW, I had sockets on my board, making the swap really easy. As opposed to NE553x's, OPA2134 has FET inputs, and thus very high input impedance like the TL072's.
You could also look at the OPA2132, which is less common, but has slightly better specs than the OPA2134 - at double the price.
Good luck with your tweaking.
/ Pelle
I've built some stuff using TL072, since they are very cheap. After
finishing my project, I replaced the TL072 witch OPA2134's and
the sound definitely improved. BTW, I had sockets on my board, making the swap really easy. As opposed to NE553x's, OPA2134 has FET inputs, and thus very high input impedance like the TL072's.
You could also look at the OPA2132, which is less common, but has slightly better specs than the OPA2134 - at double the price.
Good luck with your tweaking.
/ Pelle
Thanks
Hey thanks guys.
I already use the solder tails(sockets) and a tube pre-amp stage is out of the question here. Besides, it's already the best tube emulation amp on the market.
I ended up going with OPA2604's after trying many other suggested op amps. They are a bit smoother and richer sounding than the TL072's but not by a whole lot.....not like they were in my distortion pedal!
Anyway is there anything better out there?
I was still considering geting two AD825's and using a two single op amp to dual op amp converter that is also pinned for use in a DIP-8 socket. Maybe even AD627's. It won't be cheap though. My amplifier head uses 5 dual op amps.
Hey thanks guys.
I already use the solder tails(sockets) and a tube pre-amp stage is out of the question here. Besides, it's already the best tube emulation amp on the market.
I ended up going with OPA2604's after trying many other suggested op amps. They are a bit smoother and richer sounding than the TL072's but not by a whole lot.....not like they were in my distortion pedal!
Anyway is there anything better out there?
I was still considering geting two AD825's and using a two single op amp to dual op amp converter that is also pinned for use in a DIP-8 socket. Maybe even AD627's. It won't be cheap though. My amplifier head uses 5 dual op amps.
tweak of KAWAI PN100 digital piano
I am newbie on this list so hello everyone.
What I would like to do is to upgrade Kawai PN100 digital piano
some 2 years old.
I am seasoned hifi tweaker and not solder-gun shy but never tried my luck on anything like this.
Any ideas or pointers to information are welcome.
TIA
I am newbie on this list so hello everyone.
What I would like to do is to upgrade Kawai PN100 digital piano
some 2 years old.
I am seasoned hifi tweaker and not solder-gun shy but never tried my luck on anything like this.
Any ideas or pointers to information are welcome.
TIA
trial & error?
I am also looking to upgrade op amps. I am rebuilding an ADA MP2 (tube pre-ampw/ effects)with better resistors, caps, etc. This unit has a multitude of op amps. I would keep the manufacturers in business just trying them all out. Anyone have any experience in what sound quality changes different op amps produced?
I am also looking to upgrade op amps. I am rebuilding an ADA MP2 (tube pre-ampw/ effects)with better resistors, caps, etc. This unit has a multitude of op amps. I would keep the manufacturers in business just trying them all out. Anyone have any experience in what sound quality changes different op amps produced?
If I were to build an ADA-clone I would go for the OPA2134 from BurBrown. Low noise, fast, FET input and low price.
They are very neutral sounding too. The ADA is a tube preamp, right? That means that the tube will do the coloring of the sound.
OPA2134 is a dual opamp - if you need a single opamp version go for the OPA134PA instead.
Best,
Peter
They are very neutral sounding too. The ADA is a tube preamp, right? That means that the tube will do the coloring of the sound.
OPA2134 is a dual opamp - if you need a single opamp version go for the OPA134PA instead.
Best,
Peter
Phill,
Hopefully you already know the site called: http://www.adadepot.com/
It's a dream come true. All the manuals & schematics for the whole ADA range to download. I have learned a lot from that site.
BTW: I'm designing my own guitarpreamp at the moment.
- Peter
Hopefully you already know the site called: http://www.adadepot.com/
It's a dream come true. All the manuals & schematics for the whole ADA range to download. I have learned a lot from that site.
BTW: I'm designing my own guitarpreamp at the moment.
- Peter
Peter,
I have used an ADA MP-1 since they first came out. I have seen many imitators come & go, but none compare to the quality & sound of an ADA. I gigged with mine for at least 10 years before semi-retiring. Now I use it for recording and playing in our church band. It is versatile enough to allow all kinds of sounds.
I have found the ADA Depot site and have downloaded the schematics I needed. I am now replacing the resistors in the MP-2 with Vishay/Dale 1% metal film, replacing diodes with MUR type & upgrading the capacitors. After I clean up the signal & power paths, I will experiment with op amps.
Keep me posted on the progress of your amp design. If I were to design a pre-amp, I would follow the ideas that made ADA such a cult classic.
Thanks for your interest.
Phill
I have used an ADA MP-1 since they first came out. I have seen many imitators come & go, but none compare to the quality & sound of an ADA. I gigged with mine for at least 10 years before semi-retiring. Now I use it for recording and playing in our church band. It is versatile enough to allow all kinds of sounds.
I have found the ADA Depot site and have downloaded the schematics I needed. I am now replacing the resistors in the MP-2 with Vishay/Dale 1% metal film, replacing diodes with MUR type & upgrading the capacitors. After I clean up the signal & power paths, I will experiment with op amps.
Keep me posted on the progress of your amp design. If I were to design a pre-amp, I would follow the ideas that made ADA such a cult classic.
Thanks for your interest.
Phill
soo?
so changing the OP amp in an amp will create a different sound? For example, if i wanted a different type of distortion i could swap the OP and get a different sound? OOO this sounds cool.. heck build an 8PXT switch (X being however many chips you throw in) and switch it for different sounds.. haha
so changing the OP amp in an amp will create a different sound? For example, if i wanted a different type of distortion i could swap the OP and get a different sound? OOO this sounds cool.. heck build an 8PXT switch (X being however many chips you throw in) and switch it for different sounds.. haha
switching op amps
Generally switching op amps won't really change your distortion sound.
You may get an increase in treble, bass or mids, possiblly all three or only in one. One chip may simply sound smoother while another sounds harsher.
A couple other things that may happen is you might get a huge drop in gain or it may just be a moderate decrease.
The other is it may totally change your sustain. Several chips I used did this really bad. My sustain went from say 10 seconds to maybe 4 or 5.
The best duel op amp to use is from Texas Instruments. The Burr Brown OPA2604. It won't change your sound persay but it will improve it dramatically. It is very smooth and tube like sounding. It makes solid state sound warm or warmer than it already did. There is also a single op amp version the OPA604.
Most guitar amps use duel op amps.
So far in the guitar pedals I have built the 2604 overall sounds the best. The best sounding chips I have used are:
OPA2604 of course, the NTE858M which is a higher end replacement for the LF353 which also sounds quite good. Lastly would be the TLC072 which is probably the highest end chip that the big name companies use in their products.
Bottom line is in general the 2604 is the very best.
More expensive doesn't generally mean better. The NTE858 is like 3 dollars and some change. The 2604 is somewhere around a buck. These two chips sound a lot alike. The 858 is a little harsher and more defined in the bass and treble. The 2604 is smooth through all 3 bands.
Generally switching op amps won't really change your distortion sound.
You may get an increase in treble, bass or mids, possiblly all three or only in one. One chip may simply sound smoother while another sounds harsher.
A couple other things that may happen is you might get a huge drop in gain or it may just be a moderate decrease.
The other is it may totally change your sustain. Several chips I used did this really bad. My sustain went from say 10 seconds to maybe 4 or 5.
The best duel op amp to use is from Texas Instruments. The Burr Brown OPA2604. It won't change your sound persay but it will improve it dramatically. It is very smooth and tube like sounding. It makes solid state sound warm or warmer than it already did. There is also a single op amp version the OPA604.
Most guitar amps use duel op amps.
So far in the guitar pedals I have built the 2604 overall sounds the best. The best sounding chips I have used are:
OPA2604 of course, the NTE858M which is a higher end replacement for the LF353 which also sounds quite good. Lastly would be the TLC072 which is probably the highest end chip that the big name companies use in their products.
Bottom line is in general the 2604 is the very best.
More expensive doesn't generally mean better. The NTE858 is like 3 dollars and some change. The 2604 is somewhere around a buck. These two chips sound a lot alike. The 858 is a little harsher and more defined in the bass and treble. The 2604 is smooth through all 3 bands.
A comment to mister Checcks:
I generally agree with you about the OPA2604. One thing though; It's quite noisy compared to other opamps.
This is what I do about it: Looking through the schematic of a specific solid state amp, I deside where to place the OPA2604.
I generally place is where I have little gain in the circuit but wnat the coloring.
Where I have lot's of gain going on I place opamps like OP2134, OP37 or OPA627. These are quiter but doesent color as much as OPA2604. This way I get best of both worlds.
I'm about to try out the LT1115 for gainstage - one of the quitest opamps you can get.
It's noise is max. 1.2 nV at 1Khz where OPA2604 is about 10nV.
It's there some of you who have tried it out?
I generally agree with you about the OPA2604. One thing though; It's quite noisy compared to other opamps.
This is what I do about it: Looking through the schematic of a specific solid state amp, I deside where to place the OPA2604.
I generally place is where I have little gain in the circuit but wnat the coloring.
Where I have lot's of gain going on I place opamps like OP2134, OP37 or OPA627. These are quiter but doesent color as much as OPA2604. This way I get best of both worlds.
I'm about to try out the LT1115 for gainstage - one of the quitest opamps you can get.
It's noise is max. 1.2 nV at 1Khz where OPA2604 is about 10nV.
It's there some of you who have tried it out?
huh?
All but one of the formentioned are single op amps and quite honestly I've never had any noise problems whatsoever from the 2604. Which is a duel op amp.........I've never heard of it coloring the sound drastically or any other op amp doing so for that matter. Really what it did for the sound in my applications was improve what was there.
Are you using it in tube circuits??
As far as most guitar related circuits go be it solid state amps or pedals...most use duel op amps not single.........
Anyhow I replaced 5 duel op amps in 120 watts RMS guitar head and the only place I had a noise problem was the reverb circuit. Easy solution here was to go back to the TLC072 the reverb originally used.
The amp used all TLC072's and the sound is just smoother and a bit richer now with the 2604's. More tube like. It's actually quieter now. In fact, the specs of the OPA2604 are very similar to a 12AX7 tube.
The only duel op amp you mentioned I have used the OPA2134 and man it was a wall of noise in those circuits.
I do know the circuit you use an op amp in has a lot to do with getting noise or feedback.
The general concensus on the internet is the OPA2604 is the best duel op amp for audio related circuits particularly guitar related ones.
I've got easily over 12 different types of chips to use in my guitar amp and pedals and hands down the OPA2604 has outperformed all others. Quieter, richer, warmer, gain is smoother and my tube emulation was slightly improved. There were just improvements all around. I've used a lot of different chips too I must say.
Maybe it's just the circuits I used the 2604 in but I'm inclined to believe otherwise based on my results and the postings of countless others that swear by it as well. Anyone out to capture a bit of the smoothness and richness of tube seems to swear by it.
I'm pretty surpirised by your noise comment more than anythingbut maybe I've just been lucky. The difference in sound I've noticed with using different op amps isn't usually too different or coloring. Generally I feel it's the same sound as before but with a slight change if any. One chip might be colder or warmer. One might be more grainy. ANother might cut sustain or gain maybe both.
I think the Duel op amp I liked most next to the 2604 was the NTE858M. Even with it's noise rating being 18 v, it was still quiet for me. These two chips sound VERY much alike but the NTE858M has a grainier and raspier sound when used in a gain circuit. It has a bit bolder treble and bass where as the 2604 is even in bass,mid and treble in comparison. Oh and this ones not cheap either. Most I've spent on a chip so far: $3.63 USD plus shipment of the entire order. OUCH!
All but one of the formentioned are single op amps and quite honestly I've never had any noise problems whatsoever from the 2604. Which is a duel op amp.........I've never heard of it coloring the sound drastically or any other op amp doing so for that matter. Really what it did for the sound in my applications was improve what was there.
Are you using it in tube circuits??
As far as most guitar related circuits go be it solid state amps or pedals...most use duel op amps not single.........
Anyhow I replaced 5 duel op amps in 120 watts RMS guitar head and the only place I had a noise problem was the reverb circuit. Easy solution here was to go back to the TLC072 the reverb originally used.
The amp used all TLC072's and the sound is just smoother and a bit richer now with the 2604's. More tube like. It's actually quieter now. In fact, the specs of the OPA2604 are very similar to a 12AX7 tube.
The only duel op amp you mentioned I have used the OPA2134 and man it was a wall of noise in those circuits.
I do know the circuit you use an op amp in has a lot to do with getting noise or feedback.
The general concensus on the internet is the OPA2604 is the best duel op amp for audio related circuits particularly guitar related ones.
I've got easily over 12 different types of chips to use in my guitar amp and pedals and hands down the OPA2604 has outperformed all others. Quieter, richer, warmer, gain is smoother and my tube emulation was slightly improved. There were just improvements all around. I've used a lot of different chips too I must say.
Maybe it's just the circuits I used the 2604 in but I'm inclined to believe otherwise based on my results and the postings of countless others that swear by it as well. Anyone out to capture a bit of the smoothness and richness of tube seems to swear by it.
I'm pretty surpirised by your noise comment more than anythingbut maybe I've just been lucky. The difference in sound I've noticed with using different op amps isn't usually too different or coloring. Generally I feel it's the same sound as before but with a slight change if any. One chip might be colder or warmer. One might be more grainy. ANother might cut sustain or gain maybe both.
I think the Duel op amp I liked most next to the 2604 was the NTE858M. Even with it's noise rating being 18 v, it was still quiet for me. These two chips sound VERY much alike but the NTE858M has a grainier and raspier sound when used in a gain circuit. It has a bit bolder treble and bass where as the 2604 is even in bass,mid and treble in comparison. Oh and this ones not cheap either. Most I've spent on a chip so far: $3.63 USD plus shipment of the entire order. OUCH!
To MrCheecks: I guess that you have been lucky not hitting the noise floor of the OPA2604.
It's quite strange, but an 25 years old opamp - the NE5532 - has less noise.
OPA2604 has 10nV where NE5532 has 3.5nV. Quite a difference....
I think it's a matter of where you place your opamps in the circuit. Also a matter of how the circuit was put together. If it's a clever design you will have very little noise.
Problem is, most solid state guitar amps are not very well thought out. Not in hifi terms......;-)
I play alot of acoustic guitars (Godin) and I really like when my amp is dead quiet. I'm designing my own preamp at the moment for the some reason.
It's quite strange, but an 25 years old opamp - the NE5532 - has less noise.
OPA2604 has 10nV where NE5532 has 3.5nV. Quite a difference....
I think it's a matter of where you place your opamps in the circuit. Also a matter of how the circuit was put together. If it's a clever design you will have very little noise.
Problem is, most solid state guitar amps are not very well thought out. Not in hifi terms......;-)
I play alot of acoustic guitars (Godin) and I really like when my amp is dead quiet. I'm designing my own preamp at the moment for the some reason.
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