LF03s Fully-Discrete DIP8 Opamp for MyRef Rev C or similar

[linuxguru]

As the title says, this is an offer of the LF03s fully-discrete single opamp in DIP8 pinout, which can be used in a wide variety of applications. It is a direct plug-in upgrade for the DIP8 LM318 in a MyRef Rev C or similar.

There's more information at this thread:

http://www.diyaudio.com/forums/analog-line-level/207871-lf03-discrete-opamp-2.html#post3644366

The item being offered is the LF03s SMD single opamp, fully assembled and tested, at a price of USD 25 each + s&h + PayPal fees.

The LF03d (SMD dual opamp) is also available, fully assembled and tested, at a price of USD 50 each + s&h + PayPal fees.

If interested in either unit, please send a PM or email to me:
siva dot chander at gmail dot com.

 

[linuxguru]

It is a direct plug-in upgrade for the DIP8 LM318 in a MyRef Rev C or similar.

Sorry, I have to retract this claim - the LF03s is only marginally stable in a MyRef Rev C. It's not a direct plug-in replacement for the LM318, LF01 or LM318+LF07 in a MyRef Rev C for now.

It's still perfectly fine as a discrete upgrade to just about any bipolar-input DIP8 single opamp in just about any small-signal and live-level application, where its sonics are comparable to or better than almost any monolithic opamp.

 

[linuxguru]

Pic of the LF03d DIP8 dual-opamp module (this is essentially 2x LF03s mounted on a base PCB with the DIP8 pins) :

http://img27.imageshack.us/img27/3666/hy0y.jpg

 

[linuxguru]

*Bump* - successfully used an LF03d to upgrade the I/V in a Kenwood DP-1001, where a lot of monolithics choke due to relatively low rail voltages:

http://www.diyaudio.com/forums/analog-line-level/207871-lf03-discrete-opamp-3.html#post3660276

No issues with the LF03d, except physical clearance between the DAC riser card and the transport, which were successfully resolved.

 

[m4rk1z]

Hi!

Can this work in a Playstation1 ?
The PS1 use njm2100 dual opamp with 5v as power source.

Thank you.

 

[linuxguru]

Can this work in a Playstation1 ?
The PS1 use njm2100 dual opamp with 5v as power source.

If it is a DIP8 (not SOIC8) and has rails of +/- 5V for the opamp, then it should work in principle. If the opamp power supply is just single-rail +5V, it's very tight and I'd recommend a low-rail monolithic like AD8022, LM6152 or LM6172 instead.

 

[lordearl]

This looks like a great opamp.
Would it be suitable in the attached circuit I'm currently building?

The OPA627 (two singles - one per channel) is used as the i/v converter, and the OPA2134 is used as a 2nd order low pass filter.

 

[linuxguru]

Yup, it will work in both locations - i.e. for the two I/Vs, the LF03s (single) will be a direct DIP8 substitution, while the LF03d (dual) can substitute the DIP8 dual. The LF03 is a BJT-input opamp, but input biasing does not seem to be an issue in this circuit.

 

[lordearl]

Brilliant - do you think the opamps will fit in the space provided?
Here's the board:
DAC with two PCM1704

 

[linuxguru]

The lowest OPA2134 location looks like a tight fit, because of the connector below it as well as relatively low clearance to the OPA627 above it. However, it may possibly fit with the use of 1 or 2 stacked DIP8 socket(s) as a spacer at that location.

Alternatively, just use a monolithic for the LPF and discretes for the I/Vs only (the I/Vs are more critical for sonics).

 

[Blondie]

I bought one years ago, I am very satisfied! This is a great opamp!
I used opamp in Lovely Cube.
Thanks Siva!

 

[afj]

i just purchased the LF03D opamp for my weiliang Ak4495 dac.

as with most users of the weiliang ak4495+ak4418, i too experienced some harshness and inconsistencies with the dac. with reviews and after speaking with siva (linuxguru) i decided to go with unit


its an easy installation - pull out the old opamp and pin this one in. whatever apprehensions i had with the dac were ironed out after this change. the sound is more dynamic and airy now. there was a slight flabbiness around the edges previously which is now tightened up, also resulting in better sound separation. and overall it sounds much more refined and smoother now. and whatever inconsistencies that were there previously have now gone away. definitely worth the upgrade. the inconsistencies used to stand out previously and now im enjoying the music a lot more. it has brought a lot more balance to the overall sound.