Tl074, Opa4134, Lme49740 - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 20th June 2007, 11:04 AM   #1
ztan is offline ztan  Australia
diyAudio Member
 
Join Date: Nov 2003
Location: Newcastle
Default Tl074, Opa4134, Lme49740

The balanced to unbalanced converter at the front end of my Perreaux 8000C comes stock with a TL074 quad opamp (only using 2 out of 4 channels) installed.

I decided to try some upgrades to it:

TLE2074 - listed by TI as a significant upgrade to the TL074 - staging was a bit more accurate and bass sharper, but sonically sounded really quite similar to the TL074

When I first installed the OPA4134, it distorted at high preamp volume levels, and the LME49740 distorted at low levels. Fault traced to the Perreaux 1985 method of power supply to the balanced line reciever - dropping +/-112V to 15V using a resistor and Zener. Using the stock resistor, current flow was limited to around 14ma and both the OPA4134 and LME49740 idle at around 20ma. Resistor value was dropped to allow more current flow and problem was solved.

OPA4134 - installed with a DIP-SOIC adapter. Opened out the soundstage and brought in the "laidback Burr Brown sound". Some complain of tubby bass but the bass is really not at all tubby with the Perreaux output stage driving my speakers (11" Focal bass drivers). The real strength here is the timbre of the instruments. My wife (an ex-orchestral musician) came down to the listening room saying that my system was tolerable for the first time ever.

LME49740 - this is a new National low noise opamp release this year and I decided to give it a run. Bass was slightly cleaner than the OPA4134, but trebles verged on sibilant - I suspect many would call this "accurate"

After extended listening, I have left the OPA4134 in. The timbre of the instruments is so much closer to live music in my system than most systems that I have listened to. The LME49740 sounded cleaner initially and more detail was immediately apparent, but the treble was too prominent in my setup.

I guess the next thing will be to try something like the OPA627 or possibly the new OPA827, as I seem to like the Burr Brown sound best.
  Reply With Quote
Old 20th June 2007, 12:41 PM   #2
sandyK is offline sandyK  Australia
diyAudio Member
 
Join Date: Apr 2007
Location: Sydney
Default TL074 OPA4134 LME49740

I found exactly the same with the dual versions of those I.C.s as regards SQ. For that same reason I am using a SOIC OPA2134 in my PC soundcard instead of the LM4562
SandyK
  Reply With Quote
Old 20th June 2007, 01:13 PM   #3
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Hi Ztan,
try using a dual with a convertor to fit the 14pin DIL.
The two channels will run a little bit cooler and take less out of the resistor/Zener combination.
Once you have the two channel conversion sorted, that opens up the chip options.
Check to see if unity gain stability is required. Most duals are stable but there are a few that are not eg. opa2228.
__________________
regards Andrew T.
  Reply With Quote
Old 23rd June 2007, 10:53 AM   #4
ztan is offline ztan  Australia
diyAudio Member
 
Join Date: Nov 2003
Location: Newcastle
Quote:
Originally posted by AndrewT
Hi Ztan,
try using a dual with a convertor to fit the 14pin DIL.
The two channels will run a little bit cooler and take less out of the resistor/Zener combination.
Once you have the two channel conversion sorted, that opens up the chip options.
Check to see if unity gain stability is required. Most duals are stable but there are a few that are not eg. opa2228.
Running a dual converter to fit the 14DIL or 2x OPA627 was my next step. I'm also probably going to go to a dedicated power supply to see if getting the Zener out of the power supply makes a difference.

Anyone tested the OPA827 prototypes yet?
  Reply With Quote
Old 23rd October 2013, 07:12 PM   #5
diyAudio Member
 
afshindiy's Avatar
 
Join Date: Jan 2013
Location: Tehran
hi

I love LME49740
I test 3 chip opa 4134 & lme49740 & Tle2074
in my test better chip for master opamp is Lme49740 and handling & Transport audio signal TL is better than tle ... tle is low detail in my hear...
opa 4134 The sound is a lie ... especially in the bass.

thank.afshin
  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
OPA4134 x TL074 - Sound Differences -_nando-_ Chip Amps 41 25th December 2013 03:50 PM
LME49600/LME49740 Headphome Amp theAnonymous1 Solid State 28 31st January 2010 03:25 AM
Burnt my finger - OPA4134 Ridin '24'z Chip Amps 8 11th April 2008 11:11 PM
WTB:LME49710 and LME49740 Ryssen Swap Meet 5 4th June 2007 08:38 PM
Replacement for tl074 puppyslugg Parts 0 4th June 2002 09:00 AM


New To Site? Need Help?

All times are GMT. The time now is 02:58 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