better buffer then 5532

[wleediy]

I have a tube amp with 5532 as an input and output buffer. I am thinking of using BB2132/2134 which I have handy to replace, has any one tried it and if it is better then 5532?
Also what would be a good buffer op amp that is pin compatible? I know BUF03 is great, but no familiar with the spec and if they are available. I read from one post that AD843 is an equivelent in sound...

tks

WLEE

[Gasho]

If we talk about buffers, why don´t you try a discrette buffer with one or more transistors, from SE to diamond circuits.
I made some simple output buffers in PP, SE(FET) and diamond connection and they all outperform a stupid OP as a buffer. It is a most supid way to use OP in signal path.

[wleediy]

I think so too! Really I hate to think a million transistor being there Just as buffer! In my CD mod I did use a single NPN direct coupled to the DAC output for collector output and like it that way. I think BC548C with 2K at C and 300 ohms at E, 15 Volts B+, and 2.7V DAc output.
Why did you use FET instead of bipolar? Can you post some of your topologies? I am not so familiar with FET...

tks!

WLEE

[wleediy]

I always fancy a pair of NPN/PNP or N/P juction FET as a buffer with bipolar PS, but never really tried it, and do not have the confident I can get it right. Though of course I like just to build a silple circuits, but many told me how great is CCS and cascode is, and I must try it....! So will a simple circuit do it,m or I need CCS etc..??! In both cases appreciate a completed diagram, with +/- 15 V PS environment.

tks and best rgds

WLee

[tedr]

Originally posted by wleediy
I have a tube amp with 5532 as an input and output buffer. I am thinking of using BB2132/2134 which I have handy to replace, has any one tried it and if it is better then 5532?
Also what would be a good buffer op amp that is pin compatible? I know BUF03 is great, but no familiar with the spec and if they are available. I read from one post that AD843 is an equivelent in sound...

tks

WLEE

OPA2134 is a FET input device, in a low noise application with low source impedance the 5532 will be superior. that's the biggest difference. Is your tube amp providing a lot of gain? that's when low noise is valuable.
The good thing is they were both designed for audio, that's important when chosing opamps. The 5532 is MUCH cheaper than the OPA.

[wleediy]

hi Ted,

I have tried both of them, and the 5532 is grainny to my ears which I am very familiar with after listening to it all the time up to the 90s. I do remember when I first build 5532 in the early 80 or late 70 as RIAA phono amp, wow, they sounded so musical! Don't know if my ears are not so good now, or that we are spoiled to good sound!
find the 2032 not grainny, sounded smoother and extenses, but a bit hard. Actually TLE2072 sounded better then 2032 in many way, except it is a bit fatiquing after a while, the sound is probably a bit harder then 2132. Yesterday I tried higher biasing with 1.8K from the output to -ve PS, and it sounded great now. I came a cross an article in headwiz I think which uses 44 op amp as power amp. It uses op amp in pairs, with 1 connecting the output to the -ve, and anpther one with the output to +ve which I think makes a lot of sense. I will try to build a line stage this way one day!

I still want to try buffer with discrete FET or MOS FET to compare.
Best rgds

William Lee