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Active Monitor Pops after Op Amp Swap
Old 1 week ago
  #1
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Brian M. Boykin's Avatar
Active Monitor Pops after Op Amp Swap

Short of the long is I was replacing a broken trim pot on my Active Event 20/20’s and noticed it’s packed full of tl072’s. So I got the “while I’m in here bug” and soldered in sockets, decoupled the power rails, and dropped in lme49720’s. Now when I power the monitor on it pops and the drivers cycle through their full range of motion. It never did this before and the other one does not which I haven’t been in. I’m figuring it’s DC and the offsets are off. Any other explanation? Is it time for a PSU filter cap change? They’re probably 15 y/o at this point. I do follow protocol and power them on last and down first.
Old 1 week ago
  #2
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Why not check the outputs of the op amps for dc ?
Old 1 week ago
  #3
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Quote:
Originally Posted by enginefire View Post
Why not check the outputs of the op amps for dc ?
I will. Have to open her back up. But while I’m back in there if there is another possible cause I’d like to check it while I’m at it. This is my first time playing with active monitors so I’m open to me not knowing it all. There are lots of generic box films in there that could be replaced as well as coupling caps but I’m weary as it’s a crossover network. I don’t want to disrupt the balance engineered by the original designer. I have the test equipment to compare a modded one to the unmodded one so the plan was to do some baby steps at the beginning. I can drop tl072’s back in if the frequency response goes south. Initial sweeps using REW show an almost identical frequency response to the unmodded one and to the pre mod of itself. So the swap just added the pop.
Old 1 week ago
  #4
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TL072 are actually pretty respectable op amps.

There may be a turn on/off characteristic that is not on the data sheet... I wouldn't know, I never messed with the modern uber op amps. As I recall different devices can have dramatically different turn-on/off behavior.

You can try a different 49720 in the same socket to see if it is one bad puppy.... if both act exactly the same it may be the device just doing what it does.

After turn-on perturbations settle down is it noticeably quieter/cleaner than tl072?

JR
Old 1 week ago
  #5
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I think changing op amps counts as disrupting the original designers engineering balance!
Personally, if it ain’t broke...
Does the modded one sound better?
Changing the caps will, likely drastically, change the sound of the amp imho. Unless you are sure you are upgrading the part, you might just fall into the trap of “ohhh I like it, it sounds different than it did before”... different rather than better.

If is it dc on the outputs, you would have to add a cap to block it after the op amp. Check if one is there already, it could be that they used 72s because they could get rid of the dc blocking cap and improve the sound quality.

It also might be something else! Do you have a scope?
Old 1 week ago
  #6
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samwinston123's Avatar
 

Check all the outputs on the LME's, could be a bad chip or a severe offset.

TL072 is JFET input so input bias current is quite low at 65pA, vs 10nA for the bipolar input LME. Input offset for the two is also quite different: 3mV for the TL, 0.1mV for the LME. Biasing resistors might be too large, or perhaps they added an offset trim that isn't reacting well with the LME's.

Last edited by samwinston123; 6 days ago at 09:24 PM..
Old 6 days ago
  #7
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I’m gonna answer both of you, enginefire and John, with one post.

Couldn’t tell a difference sound wise from the little listening I did but doesn’t matter because double blind tests would have to be conducted to signify it an improvement. The measured frequency response on the sweeps I did plotted on top of each other.

The ultimate reason I swap in 49720’s are the lower noise and distortion. I ride the coat tails of those on this forum that have test gear to test and vouch they are an improvement in this regard. There are 5 in one monitor. I’m OTB so it adds up across a 32/8/2 console, 10 to 15 compressors, and outboard EQ’s. The 49720’s tend to be very neutral and do not add or take away. I typically use them in EQ’s and in gear that I want to be invisible, thus the reason for using them in my monitors.

I have a scope but I’m still learning how to use it to solve and measure.

I had to unwind the PCB layout because I haven’t found schematics. I’ll look down the line for a coupling cap. I’d rather not add one. Instead I’ll try a 5532. Also, the lme’s are somewhat suspect. Bought off EBay. Texas Instruments is making the 49720 under the original part name, lm4562. I may trash the 20 or so I have and start over. I have loads of tl072’s and 5532’s I’ve pulled from other gear in a parts bin.

And yes, swapping op amps is messing with the original design. But placing sockets makes for an easy reversal. Replacing the tl072’s in my console made a subtle difference (or different) from one module to another, but across an entire mix I felt it was easier and took less time to get a great sounding mix. Replacing tired caps value for value and using caps designed for audio vs the generic caps in there should, in theory, make a difference. My console is from 1980. A recap is due. The monitors on the other hand are mid to late 90’s so the caps may not be so tired, there just not an audio grade cap.

Money doesn’t grow on trees around here so I buy older yesteryear gear and upgrade components. I try not to say “mod” anymore because I rarely change values. I just drop in modern equivalents. I’ve had excellent results doing this.
Old 6 days ago
  #8
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Quote:
Originally Posted by samwinston123 View Post
Check all the outputs on the LME's, could be a bad chip or a severe offset.

TL072 is JFET input so input bias current is quite low at 65pA, vs 10nA for the bipolar input LME. Output offset for the two is also quite different: 3mV for the TL, 0.1mV for the LME. Biasing resistors might be too large, or perhaps they added an offset trim that isn't reacting well with the LME's.
This is where I get myself in trouble. I’ve been doing this long enough to completely understand what your talking about, but don’t necessarily have the skills to adjust the circuit design to account for this. Maybe this will make me learn.
Old 6 days ago
  #9
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Quote:
Originally Posted by Brian M. Boykin View Post
This is where I get myself in trouble. I’ve been doing this long enough to completely understand what your talking about, but don’t necessarily have the skills to adjust the circuit design to account for this. Maybe this will make me learn.
Test each opamp output and try swapping parts first. I’ve had a few of the LME’s go bad over the years.

If it’s a DC bias issue then the 5532’s will be worse. Their input bias current is 200nA.

If you want to replace the LME’s the price on the LM4562 went way down recently. Only $1.59 each
Old 6 days ago
  #10
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If you can get the lm4562 from a reputable dealer, it’s definitely worth a try, it used to be a big scam on eBay sanding down the labels on other op amps and restamping them with bB labels, I’m sure the same folks moved on to LME by now.

I 100% support modding gear and am in the camp of high speed op amps. They sound better to me, cleaner, and like you noted, add 32 or more channels with 5 or so chips a channel and you can really feel a difference. I did find, at least in my console, that certain opamps worked better in certain spots, so rather than swapping out all chips for one type of new chip, each channel got a combo of various chips. Mods were still required to get them to work best, ie getting them to be stable and work best sometimes needed a slightly different cap or resistor value here and there. Things would work with simple plug and play but it was definitely worth the time to change values of other components, especially caps.

Personally, and this is not to dissuade you from pursuing changing the op amps in your monitors, I think you will find more noticeable results from changing the caps in your monitors than changing the op amps!

Keep striving for the best
Old 6 days ago
  #11
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Quote:
Originally Posted by samwinston123 View Post
Test each opamp output and try swapping parts first. I’ve had a few of the LME’s go bad over the years.

If it’s a DC bias issue then the 5532’s will be worse. Their input bias current is 200nA.

If you want to replace the LME’s the price on the LM4562 went way down recently. Only $1.59 each
Yeah, I have plans to buy a couple hundred. Thanks for the input. I’m reading up on bias resistors and the lightbulb actually went off this time.
Old 6 days ago
  #12
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Quote:
Originally Posted by enginefire View Post
If you can get the lm4562 from a reputable dealer, it’s definitely worth a try, it used to be a big scam on eBay sanding down the labels on other op amps and restamping them with bB labels, I’m sure the same folks moved on to LME by now.

I 100% support modding gear and am in the camp of high speed op amps. They sound better to me, cleaner, and like you noted, add 32 or more channels with 5 or so chips a channel and you can really feel a difference. I did find, at least in my console, that certain opamps worked better in certain spots, so rather than swapping out all chips for one type of new chip, each channel got a combo of various chips. Mods were still required to get them to work best, ie getting them to be stable and work best sometimes needed a slightly different cap or resistor value here and there. Things would work with simple plug and play but it was definitely worth the time to change values of other components, especially caps.

Personally, and this is not to dissuade you from pursuing changing the op amps in your monitors, I think you will find more noticeable results from changing the caps in your monitors than changing the op amps!

Keep striving for the best
Thanks for the input. I actually used opa2134’s in the input stage on my console (Soundcraft 400b) because I felt they sounded better than the lme’s in listening tests of my reference tracks. I added 23pf caps in the feedback loop per advice from those more experienced than I. The fader buffer is an lme49710. Changing passive components always makes the biggest audible change in my experience. So much so I changed all the carbon resistors to metal film in the input modules. 52 resistors a module across 32 modules. Not just the resistors in the audio path, all of them. Still have to do the groups, master, and effects return. The console sounds pretty darn good to my ears and those that have heard it agree. I’m about to start on a new console. I picked up a 40/8/2 Soundcraft 500 Series for $40. It has issues with 4 channels and a group. That’s it. I’m building the new power supply now. It’ll give me 2 more aux sends and all the outputs, minus the direct outs and inserts, will be balanced. The 400b is ground compensated and not truly balanced. Very similar design and it already has metal film throughout.
Old 6 days ago
  #13
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Quote:
Originally Posted by Brian M. Boykin View Post
I’m gonna answer both of you, enginefire and John, with one post.

Couldn’t tell a difference sound wise from the little listening I did but doesn’t matter because double blind tests would have to be conducted to signify it an improvement. The measured frequency response on the sweeps I did plotted on top of each other.

The ultimate reason I swap in 49720’s are the lower noise and distortion. I ride the coat tails of those on this forum that have test gear to test and vouch they are an improvement in this regard. There are 5 in one monitor. I’m OTB so it adds up across a 32/8/2 console, 10 to 15 compressors, and outboard EQ’s. The 49720’s tend to be very neutral and do not add or take away. I typically use them in EQ’s and in gear that I want to be invisible, thus the reason for using them in my monitors.

I have a scope but I’m still learning how to use it to solve and measure.

I had to unwind the PCB layout because I haven’t found schematics. I’ll look down the line for a coupling cap. I’d rather not add one. Instead I’ll try a 5532. Also, the lme’s are somewhat suspect. Bought off EBay. Texas Instruments is making the 49720 under the original part name, lm4562. I may trash the 20 or so I have and start over. I have loads of tl072’s and 5532’s I’ve pulled from other gear in a parts bin.

And yes, swapping op amps is messing with the original design. But placing sockets makes for an easy reversal. Replacing the tl072’s in my console made a subtle difference (or different) from one module to another, but across an entire mix I felt it was easier and took less time to get a great sounding mix. Replacing tired caps value for value and using caps designed for audio vs the generic caps in there should, in theory, make a difference. My console is from 1980. A recap is due. The monitors on the other hand are mid to late 90’s so the caps may not be so tired, there just not an audio grade cap.

Money doesn’t grow on trees around here so I buy older yesteryear gear and upgrade components. I try not to say “mod” anymore because I rarely change values. I just drop in modern equivalents. I’ve had excellent results doing this.
If you have bought the 49720's from one of the Chinese seller on ebay then they will be 100% fake/relabelled 741's. Swapping TL0XX for LM[E]'s in the input- & output stages will make an audible difference [ONLY if decoupled properly with 100nf & 4.7uf caps on each pwr rail] . . which usually results in better clarity and in hearing more details. You won't need a blind test to notice.
Old 6 days ago
  #14
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Quote:
Originally Posted by TobyToby View Post
If you have bought the 49720's from one of the Chinese seller on ebay then they will be 100% fake/relabelled 741's. Swapping TL0XX for LM[E]'s in the input- & output stages will make an audible difference [ONLY if decoupled properly with 100nf & 4.7uf caps on each pwr rail] . . which usually results in better clarity and in hearing more details. You won't need a blind test to notice.
US seller but I’m trashing them. I think I have 20 or so. I’m buying 100 lm4562’s from Mouser. They’ll ship today and be here tomorrow. I’m in Texas.

I’ve always done the .1uf but never the 4.7uF. I see where it’s in the application notes. The 4.7 looks polarized. Is it an electrolytic? There’s plenty of room to add them. I can add them to my Mouser order.
Old 6 days ago
  #15
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I’ve never used the 4.7uf either. They would be polarized for sure, one on each rail to ground, make sure they are the right way!!
Most of the mods I’ve done already had a cap like this on each board, so I figured it kinda there I usually up these from 47 to 100uf anyhow and added the .1uf cap to decouple the rails right at the socket to a nearby ground (same ground for both caps).

Your soundcraft sounds like a great sounding board!!

Mouser is awesome... they get here the next day too and I’m in canada!
Old 6 days ago
  #16
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Quote:
Originally Posted by Brian M. Boykin View Post
US seller but I’m trashing them. I think I have 20 or so. I’m buying 100 lm4562’s from Mouser. They’ll ship today and be here tomorrow. I’m in Texas.

I’ve always done the .1uf but never the 4.7uF. I see where it’s in the application notes. The 4.7 looks polarized. Is it an electrolytic? There’s plenty of room to add them. I can add them to my Mouser order.
They are all in SOIC packages only now, so you would need adapter boards to DIP8/DIL8 as well. These boards are of good quality when buying them from Chinese ebay sellers
I'm actual using 100nf, 4.7uf & 10uf on each pwr rail. The 100nf is a Panasonic film cap, the other two are tantalums. Yes, the higher values are polarised so the positive terminal from the caps has to go to com/ground when connecting to the op-amps negative voltage input.

Btw the original LME4910/20 DIP8 chips become pretty hot when operating [a known feature of them]. That's might be an indicator to find out if your items are original or fake

Last edited by TobyToby; 6 days ago at 01:33 AM..
Old 6 days ago
  #17
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Quote:
Originally Posted by TobyToby View Post
They are all in SOIC packages only now, so you would need adapter boards to DIP8/DIL8 as well. These boards are of good quality when buying them from Chinese ebay sellers
I'm actual using 100nf, 4.7uf & 10uf on each pwr rail. The 100nf is a Panasonic film cap, the other two are tantalums. Yes, the higher values are polarised so the positive terminal from the caps has to go to com/ground when connecting to the op-amps negative voltage input.

Btw the original LME4910/20 DIP8 chips become pretty hot when operating [a know feature of them]. That's might be an indicator to find out if your items are original or fake
My gift to you for helping me.

https://www.mouser.com/ProductDetail/926-LM4562NA-NOPB

LME49710 and LME49720 end of life

Bottom of page 2 Jim Williams confirms the lm4562 is the same op amp as the lme49720. In fact, the lm4562 is the original part number. Jim did the master in my 400b in 2007 and it’s packed full of lm4562’s. Why Texas Instruments is keeping this a secret idk. Maybe they have lots of SOIC inventory of the 49720. I’m hopeful for a single 4561.
Old 6 days ago
  #18
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Quote:
Originally Posted by Brian M. Boykin View Post
My gift to you for helping me.

https://www.mouser.com/ProductDetail/926-LM4562NA-NOPB

LME49710 and LME49720 end of life

Bottom of page 2 Jim Williams confirms the lm4562 is the same op amp as the lme49720. In fact, the lm4562 is the original part number. Jim did the master in my 400b in 2007 and it’s packed full of lm4562’s. Why Texas Instruments is keeping this a secret idk. Maybe they have lots of SOIC inventory of the 49720. I’m hopeful for a single 4561.
Thanks, nice to know that Mouser still has about 1k of them in stock. I remember from about ten years ago that one of the original designers of these chips, who is a member on diy-audio, confirmed first hand that the LM4562 & LME49720 are the same device. I'm pretty sure a 4561 op-amp does not exist. It started with the LME49710
Old 6 days ago
  #19
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Quote:
Originally Posted by TobyToby View Post
Thanks, nice to know that Mouser still has about 1k of them in stock. I remember from about ten years ago that one of the original designers of these chips, who is a member on diy-audio, confirmed first hand that the LM4562 & LME49720 are the same device. I'm pretty sure a 4561 op-amp does not exist. It started with the LME49710
They have 100 less now. I don’t have a single lme49720 I didn’t buy off eBay. 100 should cover all the places I’ve put them and leave some for future projects. I’m gonna do some new listening tests with these and see if I get different results.
Old 6 days ago
  #20
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I suspect you will be shocked when you replace your eBay 49720s with the 4562s. They all should be noticeably better than 072s or 4558s , st least from what I’ve experienced.
Old 6 days ago
  #21
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Quote:
Originally Posted by enginefire View Post
I suspect you will be shocked when you replace your eBay 49720s with the 4562s. They all should be noticeably better than 072s or 4558s , st least from what I’ve experienced.
This may be why I like the opa2134 so much. I get those from Mouser and swap them into compressors. They’re also in the EQ section of my console. I’ll do some swaps and take a listen. I have 2 Aphex 651’s and a KT DN504 that Jim did and they have LME’s in them and sound great. But so do my Ashly SC55’s and my DBX 166 and they have opa’s. The struggle is real.
Old 6 days ago
  #22
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Ha for real, it’s a struggle!
The 2134s are the burr browns right? I think the 2604 was another of theirs. I liked the 2134 better iirc.
I’ll try and see what I used in my 166 and 163. Whatever it was the mods on those dbx work wonders.
I remember I used the 2134 on a few channels of my old console (tascam 3500). Funny tho I tried to swap chips on another console (it addition to a whole bunch of mods, Yamaha pm700) but it made so little difference I didn’t bother with more than the two channels I started with. The other mods did wonders though.
Old 6 days ago
  #23
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Just as a little add-on. Here two pics from my Soundcraft 8000 Masterchannel in the modding process.
Op-amps are single LME49710HA [metal can] in dual adapters. All resistors in the audio path got swapped for Dale/Vishay millitary grades. Coupling caps in the audio path are not installed yet [they will be Nichicon FG and Panasonic FR series]. All feedback caps went from ceramic to 22pf & 33pf polystyrene [or styroflex as Hans Auto Bahn said].
The decoupling caps are not connected to the com on the PCB because they are getting their own rail which connects directly to the com from the 40Amp smps [two 20A rails]
The whole channel board does not look pretty and makes a lot of work '
. . Anyways, for music we are working hybrid, no desk needed atm. For now I'm only working/DIYing on the Soundcraft when I need a bit inner Zen. No time stress. At one point the desk will be back in the mixing business of course and I'm curious about the results.

I did tests with different types of capacitors for decoupling. Tantalums gave me the most "firm" & snappy audio results from the op-amps. The worst came out from a large electrolytic cap between positive and negative rail [Soundcrafts original design]
Tants need to be at least rated for 35V in a 18V circuit. They will blow up easily when triggered by spikes/overvoltage. 25V rated tantalums did this in my tests.
I will leave them in the master channel but can't see them in all channels. They simply have an underlaying fire risk in comparision to other capacitor types [on the other hand I have fourty years old Drake equipment populated with fine working tantalums but dried out electyrolytics] Anyways, I will properly go with solid polymer caps for all the other channels. I'm not a fan of electrolytics for op-amp decoupling, I find them somehow too "slow" [especially with large capacities like 47uF or 100uF] Well, thats my truth to this day and might change tomorrow or in a year: )
Attached Thumbnails
Active Monitor Pops after Op Amp Swap-sc800_mastermodule-1.jpg   Active Monitor Pops after Op Amp Swap-sc800_mastermodule-2.jpg  

Last edited by TobyToby; 6 days ago at 04:49 AM..
Old 6 days ago
  #24
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Quote:
Originally Posted by enginefire View Post
Ha for real, it’s a struggle!
The 2134s are the burr browns right? I think the 2604 was another of theirs. I liked the 2134 better iirc.
I’ll try and see what I used in my 166 and 163. Whatever it was the mods on those dbx work wonders.
I remember I used the 2134 on a few channels of my old console (tascam 3500). Funny tho I tried to swap chips on another console (it addition to a whole bunch of mods, Yamaha pm700) but it made so little difference I didn’t bother with more than the two channels I started with. The other mods did wonders though.
I have 2 163x’s I modded. 2134’s. DBX2180a’s. Same treatment in my Symetrix 501’s. Totally different compressors after mods. I have a 501 with the Valley People VCA and I prefer the dbx units. They sound better to y ears. I plan to swap in metal films on one of the 163’s and my second 166 and see how they turn out.
Old 6 days ago
  #25
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Quote:
Originally Posted by Brian M. Boykin View Post
I have 2 163x’s I modded. 2134’s. DBX2180a’s. Same treatment in my Symetrix 501’s. Totally different compressors after mods. I have a 501 with the Valley People VCA and I prefer the dbx units. They sound better to y ears. I plan to swap in metal films on one of the 163’s and my second 166 and see how they turn out.
You guys should give the OPA1642 a try [soic only and will need an adapter] To my ears they sound better than the 2134
Old 6 days ago
  #26
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I’ve never tried to use any soic.. I hear they are making better op amps in the surface mount packaging, I just very been great at soldering that small, nor have I tried to find a good and affordable adaptor board. Last time I looked, a few years back, the adaptor board were like $5 a piece!
Old 6 days ago
  #27
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Quote:
Originally Posted by TobyToby View Post
Just as a little add-on. Here two pics from my Soundcraft 8000 Masterchannel in the modding process.
Op-amps are single LME49410HA [metal can] in dual adapters. All resistors in the audio path got swapped for Dale/Vishay millitary grades. Coupling caps in the audio path are not installed yet [they will be Nichicon FG and Panasonic FR series]. All feedback caps went from ceramic to 22pf & 33pf polystyrene [or styroflex as Hans Auto Bahn said].
The decoupling caps are not connected to the com on the PCB because they are getting their own rail which connects directly to the com from the 40Amp smps [two 20A rails]
The whole channel board does not look pretty and makes a lot of work '
. . Anyways, for music we are working hybrid, no desk needed anymore. I'm only working on the Soundcraft when I need a bit inner Zen.

I did tests with different types of capacitors for decoupling. Tantalums gave me the most "firm" & snappy audio results from the op-amps. The worst came out from a large electrolytic cap between positive and negative rail [Soundcrafts original design]
Tants need to be at least rated for 35V in a 18V circuit. They will blow up easily when triggered by spikes/overvoltage. 25V rated tantalums did this in my tests.
I will leave them in the master channel but can't see them in all channels. They simply have an underlaying fire risk in comparision to other capacitor types [on the other hand I have fourty years old Drake equipment populated with fine working tantalums but dried out electyrolytics] Anyways, I will properly go with solid polymer caps for all the other channels. I'm not a fan of electrolytics for op-amp decoupling, I find them somehow too "slow" [especially with large capacities like 47uF or 100uF] Well, thats my truth to this day and might change tomorrow or in a year: )
I used dale/Vishay in my console also. Going from carbons to metal film made a difference sonically, better, who knows? I’ve often wondered about changing caps in the feedback loop. I used WIMA’s in the EQ section. Same values. The console was internally Star grounded also. Pics speak a thousand words and just looking at those I got some questions answers. I’ve also noticed ceramics in the audio path and thought they could be changed out also. Capacitance is capacitance, but my ears can hear the difference in the different types. I’ll try some poly’s on a module. I have 8 spares I’m gonna experiment with. I added 23pf to the op amps that didn’t have them. Soldered them right to the pins on the foil side. I’ve read putting them across the resistor works also. Any input is welcome. I’m always learning.
Old 6 days ago
  #28
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Quote:
Originally Posted by enginefire View Post
I’ve never tried to use any soic.. I hear they are making better op amps in the surface mount packaging, I just very been great at soldering that small, nor have I tried to find a good and affordable adaptor board. Last time I looked, a few years back, the adaptor board were like $5 a piece!
You'll find them cheap on ebay

https://www.ebay.co.uk/itm/80Pcs-Ada...cAAOSwk2JczE3Z

I'll tape the soic op-amp with 3M blue tape in position on the pcb and on the table [half of the op amp covered by the tape so there is access to the legs on one side] and use very thin soldering wire [Kester 0.4mm] If one leg [leg 8, top right] is soldered I remove the tape completely [so there is wiggle space to re-adjust the position if needed] and finish from there
Old 6 days ago
  #29
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Quote:
Originally Posted by TobyToby View Post
You guys should give the OPA1642 a try [soic only and will need an adapter] To my ears they sound better than the 2134
I’ve thought about trying this one on a browndog adapter. I have 2 UREI la4’s I have yet to mod. They can be placed on the 4136 adapter. I like how they spec for sure.
Old 6 days ago
  #30
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Cool thanks toby, I will try this on my next project. Gotta unpacking everything still and find a workspace , but soon is soon !

Quote:
Originally Posted by TobyToby View Post
You'll find them cheap on ebay

https://www.ebay.co.uk/itm/80Pcs-Ada...cAAOSwk2JczE3Z

I'll tape the soic op-amp with 3M blue tape in position on the pcb and on the table [half of the op amp covered by the tape so there is access to the legs on one side] and use very thin soldering wire [Kester 0.4mm] When one leg [leg 8, top right] is soldered I remove the tape completely [so there is wiggle space to re-adjust the position if needed] and finish from there
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