Help upgrading opamps! - Page 3 - diyAudio
Go Back   Home > Forums > Source & Line > Analog Line Level

Analog Line Level Preamplifiers , Passive Pre-amps, Crossovers, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 26th February 2011, 12:10 PM   #21
MaxK is offline MaxK  Germany
diyAudio Member
 
Join Date: Dec 2010
I totally agree with pinkmouse, there is more to gain with outboard equipment and proper use than swapping already excellent op-amps.

I went through the same with my Dynacord CMS Mixing Console which comes with Japan Radio (JRC) NJM072 and 5532 op-amps.

All I got from the expensive AD's was higher noise floor and the OPA's sounded "duller" than the stock chips.

There is more involved in such a design as the op-amp alone, I think you'd have to modify the complete circuit.
  Reply With Quote
Old 26th February 2011, 02:04 PM   #22
Leon08 is offline Leon08  Germany
Banned
 
Join Date: Sep 2010
Location: at Home
If it were NJM072 or NJM4548 then I would recomend you to change them, but you have already good op-ams.Moreover they are SMD.This means it will be difficult to replace them.More likely you will ruin your mixer.
  Reply With Quote
Old 26th February 2011, 02:14 PM   #23
Mooly is offline Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
Quote:
Originally Posted by Leon08 View Post
If it were NJM072 or NJM4548 then I would recomend you to change them, but you have already good op-ams.Moreover they are SMD.This means it will be difficult to replace them.More likely you will ruin your mixer.
Good point, I had missed that !

All is not lost however,
Working with SMD. How to do it without specialised tools.

try and practice on something first, old remote etc
__________________
-------------------------------------------------------
Installing and using LTspice. From beginner to advanced.
  Reply With Quote
Old 26th February 2011, 02:54 PM   #24
diyAudio Member
 
purplepeople's Avatar
 
Join Date: Mar 2003
Location: London, Ontario, Canada
If a mixer were to "colour" the sound at all, I'd never know if what I was doing would translate well on other systems. There is a reason pro gear is designed as neutral as possible, even at the cost of beauty.

But it sounds like you are going to try some mods no matter what....

So, I suggest you start by swapping the opamps on only two channels (maybe the last two) and leave the buss alone for the time being. And only swap out one thing at a time on those channels, then split your well known source into both 1/2 and the modded pair and listen, listen, listen. On the first go, you'll find out if you're onto something that may be better or if you should cease and desist.

At least that's what I would do if I had the hankering to "fix" some pro equipment. Of course, I probably wouldn't for the reasons I started this post with.

BTW, what monitors are you using? I'd wager your biggest problem is the choice of near-fields.

:)ensen.
__________________
Those who claim to be making history are often the same ones repeating it.

Last edited by purplepeople; 26th February 2011 at 02:56 PM.
  Reply With Quote
Old 26th February 2011, 06:43 PM   #25
diyAudio Member
 
Join Date: Feb 2011
Location: Sanford, NC
To address some questions... I have the Projectmix, Alesis Micron Synth, Roland Juno-D Keyboard, AKG Perception 100 condensor, KRK Rokit 5s, everything else ITB..ProTools8... am going to purchase the Golden Age 73 preamp (and maybe mod), the Neumann TLM 103, and Behringer SRC2496 (maybe mod) for ad/da. This setup is mainly to record vocals, some guitar and for beat making/sequencing. I was definitely going to start with maybe channel 8 on the board for experimentation and use a socket so I can just drop different chips in. I joined this forum to get expert advice b4 I decided to take a plunge and ruin something. So keep it coming... I am still hesitant to this project... as I don't want to destroy my board.
  Reply With Quote
Old 27th February 2011, 03:02 AM   #26
diyAudio Member
 
indianajo's Avatar
 
Join Date: Jan 2010
Location: Jeffersonville, Indiana USA
Wow, so much negativism. I would be nervous about SMD, but not about trying something. First, put a dip socket in for one channel. Then try 5532 vs LM4562 or anything else. 5532 has slew rate of 6 V/usec, LM4562 has 15.Output current is 25 ma which might allow you to decrease feedback resistors and increase feedback capacitors to cut resistor noise. I think it has better noise spec, too, although specmanship may have something to do with it. See this thread about my op amp swap and power supply wars Improving a "Disco mixer" to mid-fi performance Of course I paid $15 for my mixer, and you paid $1200. I had to install better power supply bypassing, and feedback resistor cap bypass to prevent oscillations, but I haven't butchered my PCB yet. I had to suck a few solder bridges off the traces when I installed the sockets, but no other problems. I drilled a few new holes in the PCB to install more bypass caps, using a hand crank MonkeyWards drill for less violence and trash thrown around in my living room. You can also drill holes with a pin vice to keep damage and trash down. You might remove the smd part, then fly a dip socket nearby by drilling holes next to the traces and splicing in a bit of 30 ga wire. This is assuming the PCB is not multi-layer, which has its own dangers.
I did entirely replace the power supply due to the disco mixer stupid mistakes, like a 120 VAC power switch right next to the op amp PCB. But I made a whole different power supply CB out of scrap insulator board with my own holes. Your power supply in a pro mixer might be okay, not causing hum.
These little PCB's from MCM look cute for putting a dip socket on http://www.mcmelectronics.com/produc...1-110-/21-4575, getting solid core wire in and out securely, and flying it above your SMD socket on a standoff. I've got a can full of 6-32 screws & nuts, but I make the stand offs by cutting up 1/4" nylon air tubing. Use elastic stop nuts, they stay put.
__________________
Dynakit ST70, ST120, PAS2,Hammond H182(2 ea),H112,A100,10-82TC,Peavey CS800S,1.3K, SP2-XT's, T-300 HF Proj's, Steinway console, Herald RA88a mixer, Wurlitzer 4500, 4300

Last edited by indianajo; 27th February 2011 at 03:21 AM.
  Reply With Quote
Old 27th February 2011, 03:43 AM   #27
diyAudio Member
 
indianajo's Avatar
 
Join Date: Jan 2010
Location: Jeffersonville, Indiana USA
You may also want to leave your pro mixer alone, buy a ****ed out disco mixer for $40, buy new pots and play with the SIP op amps on it to see if you can make it sound better than your pro mixer. All this cap elitism has me wondering. Stacked looking plastic caps are getting real popular in switching power supplies, what do they sound like? Low self inductance probably. Not precise, but you can measure them before you use them.
__________________
Dynakit ST70, ST120, PAS2,Hammond H182(2 ea),H112,A100,10-82TC,Peavey CS800S,1.3K, SP2-XT's, T-300 HF Proj's, Steinway console, Herald RA88a mixer, Wurlitzer 4500, 4300
  Reply With Quote
Old 27th February 2011, 03:45 AM   #28
diyAudio Member
 
Andersonix's Avatar
 
Join Date: Jan 2004
Location: Silicon Valley
Although I'm no novice, I accepted that I might turn my DVD player into a brick, but I was extremely pleased at swapping an NE5532 for an LM4562 (SMD). In response to AndrewT, I only feel audiofoolish about putting it off so long....
  Reply With Quote
Old 27th February 2011, 05:17 AM   #29
diyAudio Member
 
Join Date: Feb 2011
Location: Sanford, NC
indianajo... its a great idea to use a cheap piece of gear first, just to test the sound of each opamp. A while back I made a small "$5 preamp" (Bill's Hobby Circuit Library). Guess I could just use that as my test subject to try and hear differences in these chips, although I doubt it would be possible to make it sound better than my mixer. Do you think it is possible to hear differences in these chips with such a simple circuit? (May have to use this schematic instead for dual opamp test board....http://tangentsoft.net/audio/cmoy-tu...angent-sch.pdf).

Last edited by bisszerk; 27th February 2011 at 05:27 AM.
  Reply With Quote
Old 27th February 2011, 06:54 AM   #30
Mooly is offline Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
You might be hard pushed to hear much difference with just one IC slotting it into a chain.

I find the NE5532 the most intriguing. It's claimed that 90 odd percent of all we listen too has been through many of these devices anyway... and as a straightforward amp it's pretty good. When it's used in DA convertors etc then I can tell immediate improvements in using other devices (such as the OPA2604). I came across a very interesting article some while back saying that this could be doen to HF "hash" in digital equipment causing non linearity and odd distortion products in the bipolar input stage of the NE5532

I did some serious listening to this using NE5532's and found it very hard to say for sure whether other were better.
Anyone built/listened to D Selfs precision preamp.
__________________
-------------------------------------------------------
Installing and using LTspice. From beginner to advanced.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Mod - Upgrading opamps in a yamaha av receiver dsiroky Solid State 9 11th November 2010 08:57 PM
Amplifier upgrading!!!!!!!!! psyche Solid State 11 18th June 2006 04:08 PM
FS: Power Chip OpAmps and other OpAmps & D to A Converter dtm1962 Swap Meet 4 12th January 2006 10:07 PM
Upgrading opamps in I/V stage 5th element Solid State 7 10th February 2004 09:53 PM


New To Site? Need Help?

All times are GMT. The time now is 06:11 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2