Linear Power 3002 opamp change - diyAudio
Go Back   Home > Forums > General Interest > Car Audio

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 18th August 2008, 01:08 AM   #1
invecs is offline invecs  Philippines
diyAudio Member
 
Join Date: Aug 2008
Default Linear Power 3002 opamp change

Hi! This is my first post in here. Been reading about opamp rolling in here and I've been thinking of replacing the opamps in my 3002. It has the TL072cp...I've read that the best replacement is the OPA2134. Is the replacement just a drop in thing...or do I have to change anything else? And btw, what's the difference between the OPA2134UA vs the OPA2134PA?

Thanks.
  Reply With Quote
Old 18th August 2008, 05:24 PM   #2
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
It's not always as simple as dropping in a different op-amp. Sometimes the circuits and the replacement op-amps are not compatible. In some instances, the op-amps will oscillate and can cause damage to the amplifier and/or the speakers. If you don't have an oscilloscope, you shouldn't blindly replace the op-amps. It's probably not a problem in this amp but you should know that there could be a problem.

The 'U' is a surface mount device. The 'P' is through-hole.
  Reply With Quote
Old 19th August 2008, 12:06 AM   #3
invecs is offline invecs  Philippines
diyAudio Member
 
Join Date: Aug 2008
I see. I know quite a few people who tries to mod things...and almost ending up changing everything...kinda like a domino effect.

Thanks for the reply, Perry.
  Reply With Quote
Old 19th August 2008, 06:12 AM   #4
diyAudio Member
 
Join Date: Dec 2005
Location: Northern California
I have seen some of the TIPs modded PA-2's and such and when Burr-Brown or AD op-amps get inserted in these it seems that several capacitors in the circuit seem to get changed also. Along with the higher current draw these op-amps have you might be looking at a significant drop in the supply rails unless the power supplies are beefed up accordingly.

It looks a lot easier then it is, and requires significant engineering prowess to solve the issues you might create.

Plus I would start by cleaning up the power supply of ANY Linear Power product first, then worry about the overall audio circuitry...Hope this helps
  Reply With Quote
Old 19th August 2008, 07:11 AM   #5
invecs is offline invecs  Philippines
diyAudio Member
 
Join Date: Aug 2008
I see. Maybe that's why TIPS doesn't have mods for the 3002.

I don't have any issues on how it sounds (it sounds good in fact)...it's just my spare amp and just want to play with it like some of you guys here are doing. I guess I'll just leave it as it is.

Thanks for the reply.
  Reply With Quote
Old 19th August 2008, 12:37 PM   #6
manina is offline manina  Germany
diyAudio Member
 
Join Date: Mar 2008
Location: Where the work is
Quote:
Originally posted by 1moreamp
I have seen some of the TIPs modded PA-2's and such and when Burr-Brown or AD op-amps get inserted in these it seems that several capacitors in the circuit seem to get changed also. Along with the higher current draw these op-amps have you might be looking at a significant drop in the supply rails unless the power supplies are beefed up accordingly.

It looks a lot easier then it is, and requires significant engineering prowess to solve the issues you might create.

Plus I would start by cleaning up the power supply of ANY Linear Power product first, then worry about the overall audio circuitry...Hope this helps

Hi, can you elaborate a bit more on the last sentence? Why you are suggesting this? As I have few LP, I'm interested on any improvement that can be applied. Thanks
  Reply With Quote
Old 19th August 2008, 04:54 PM   #7
diyAudio Member
 
Join Date: Dec 2005
Location: Northern California
LP's amplifiers designs are OK, nothing really special, but they are functional, and fairly durable. Simple to repair for the most part. But the power supply just never impressed me, and I feel there is ample room for improvement in this area first before I would consider any upgrade to the basic amplifier channels.

If you look at say SoundStream, PPI, Diamond/Esoteric and many others they all added toroidal type noise chokes to the rails just after the main rail caps. They didn't do this for fun. It was done to smooth out the DC power and to block power supply noise from the audio sections.

LP amps could all surely use a power supply upgrade IMO. Theres a old rule about stereo that most people don't pay attention to much and that rule is " You must have power to make power", and hand in hand with that rule goes the secondary that " the power you have must be stable clean and useful"

Most folks overlook how important good clean ample DC power is in the picture of amplification. And I just feel that LP lets me down in the power supply area.

DC Preamp who worked for LP stated here on this forum that the Power supplies sag under load. among other things that get by to the amp channels. I just feel that it would be in everyones best interest to solve some of the weaknesses before you go throwing studio grade devices into these fairly average car amps.

No use in having ultra grade devices coupled with LOW grade power sources IMO. Plus I think it would amaze most people how much improvement could be gain by working with whats already inside the amp before jumping to add-ons that only amplify the original problems and issues the basic amp already had looming inside.

Again this is my opinion, but I hope you find it useful. I always found that the donkey pulls the cart, not the other way around. I hope you can see my line of thinking in this area.


Side note: the designer of the LP amps now works for TRU and if you notice he has upgraded his power supply designs considerably and has left transistor power supplies behind for all mosfet power supply design. Transistor power supplies left the car audio scene many years ago and I must say with my blessings. If it were up to me I would completely remove the old LP power supply and build my own all mosfet SMPS as a outside power source to supply the amp clean stable cool remote power to the amp. but thats just my line of thinking....
  Reply With Quote
Old 19th August 2008, 09:13 PM   #8
manina is offline manina  Germany
diyAudio Member
 
Join Date: Mar 2008
Location: Where the work is
Thanks! Crystal clear.

I agree the power supply is key to get a good sound out of an amp - it's just that I found the LP better than many other amps I listened (including PPI) so I'm interested in how can be further improved.

Unfortunately TRU is quite rare here in Italy so I can not make any comparison.
  Reply With Quote
Old 20th August 2008, 05:04 AM   #9
diyAudio Member
 
Join Date: Dec 2005
Location: Northern California
Check out their web-site they openly post the insides of their products, most of which still use TO-3's ...Some things never get old, if you know what I mean...
  Reply With Quote
Old 23rd August 2008, 05:28 AM   #10
winslow is offline winslow  United States
diyAudio Member
 
Join Date: Aug 2005
The designer of the LP amps does not work at or for Tru. Jerry has been at Kicker for a number of years though.
  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
FS: Linear Power 3002 Torbar Swap Meet 0 21st February 2009 04:53 PM
Linear Power 3002? Torbar Car Audio 6 13th November 2008 11:43 AM
Problem with Linear Power 3002 kappa546 Car Audio 3 1st October 2008 08:09 PM
3002 linear power on life support amc32 Car Audio 10 8th April 2008 07:31 PM
linear power 3002 help amc32 Car Audio 0 14th March 2008 07:30 PM


New To Site? Need Help?

All times are GMT. The time now is 02:14 AM.


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