Sorry, the scope is a HungChang 5510 (100mhz) with a dual timebase so you can highlight any part of the scan and expand it.
The sig gen used today was a Tenma 72-5015 2mhz function generator.
I have an old treasured Wien bridge osc too,
http://www.diyaudio.com/forums/parts/126467-belco-sig-gen-age-info-etc.html
The sig gen used today was a Tenma 72-5015 2mhz function generator.
I have an old treasured Wien bridge osc too,
http://www.diyaudio.com/forums/parts/126467-belco-sig-gen-age-info-etc.html
Never seen an Amber one 
Tenma here...
Tenma 72-5015 Sweep Function Generator - eBay (item 280435739550 end time Dec-15-09 05:30:30 PST)
Tenma here...
Tenma 72-5015 Sweep Function Generator - eBay (item 280435739550 end time Dec-15-09 05:30:30 PST)
Some real world examples of substituting opamps without optimising anything. The circuit is a simple inverting configuration gain of 1 buffer with 100k feedback and input resistors. The circuit is on a proper PCB.
The output was at 2 volts peak to peak
Hover cursor over each for details
You keep completely overlooking the application thing that you so much pretend to strenghten with your proof. Please try the same thing in a circuit like that shown in the CS4398 datasheet (differential to single ended converter + low pass filter).
That you showed is a very favorable circuit for seeing opamps behave singularly.
many ppl including 12bass and majkel also find dual opamps worthless...even TI acknowledges the problem on the OPA1612. I will never use any duals ever again.I think you're talking by hyperboles, as usual
but is it compatible w/ DIP8 sockets somehow? I don't think so
very nice, thanks!
A-GD also put some of these at the bottom of their webpage: Audio-GD OPA
well, ideally a manufacturer that offers swappable DIP8 sockets should also make damn sure to decouple them and what not? there appears to be means to make rolling easier? my Prodigy HD2 has WIMA caps close to the DIP8 sockets.
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LOL! Worthless! Hyperbole is not enough!!
I remember how I preferred the $.70 LME49723 on the basis of sound quality (mainly for transparency, keeping the musicality) to a very good single FET opamp like the OPA132UA. This means that based on sound quality, I'd prefer the LME49723 to about any FET opamp (LT1122, OPA627, OPA827... save possibly the ADA4627-1).
So you see... there are more substantial reasons for or against an opamp than whether it's single or dual. For instance...: whether it is a bipolar or not.
And the LME49725 might be even better...
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What is extremely misleading, instead, is to pretend that once you've optimized your 30 KHz square wave response, even in a real world application, all opamps are going to sound about the same. Well...not only misleading...this is daydreaming.
So I hope you can see now why just swapping devices without any measurement or basic optimisation is a little misleading
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but is it compatible w/ DIP8 sockets somehow? I don't think so
Some tricky perfboard interface could be made I would guess. We are DIY, aren't we? And we could name it Bluedog or something.
Has this JE990 been tested in that big piece of work by Samuel Groner? I'm not at home right now and the computer is slow...so better not open that pdf
This looks like it's going to run for ever lol
Andrea... I have found square wave testing to be an extremely useful tool for evaluating designs. 30khz may be extreme... however that overshoot etc is visible at 100hz too... but won't photograpgh easily, not with a £29.99 camera... it's to faint. And I would certainly like to see if there were any unwanted HF oscillation in the mhz region too.
What I wanted to show was that very tiny changes in one component (just compensation... nothing else... and there is more that can be done) have a huge effect on performance. Until you level the playing field how on earth can you compare different opamps sonically.
You may like a particular one that does exhibit ringing or overshoot in a given application... but unless you have a level field by optimising your design how can you possibly make meaningful comparisons.
Andrea... I have found square wave testing to be an extremely useful tool for evaluating designs. 30khz may be extreme... however that overshoot etc is visible at 100hz too... but won't photograpgh easily, not with a £29.99 camera... it's to faint. And I would certainly like to see if there were any unwanted HF oscillation in the mhz region too.
What I wanted to show was that very tiny changes in one component (just compensation... nothing else... and there is more that can be done) have a huge effect on performance. Until you level the playing field how on earth can you compare different opamps sonically.
You may like a particular one that does exhibit ringing or overshoot in a given application... but unless you have a level field by optimising your design how can you possibly make meaningful comparisons.
Oh my... Salas, you are a moderator? I must start treating you better..
Only a regular member if I don't post with a cop's hat smiley.