pair of diff amps* initially. THAT1240 are a particularly good way of doing it and gain extra heresy points. Given the cross talk of vinyl I do not expect it to be a huge improvment over simpler methods🙂 Have borrowed Wayne's sketch as quicker than redrawing.
*Opamp/diffamp... Scott W will probably pick me up as they are the same thing, but the precision resitors in the 1240 make it particularly useful for these sort of things.
*Opamp/diffamp... Scott W will probably pick me up as they are the same thing, but the precision resitors in the 1240 make it particularly useful for these sort of things.
Attachments
Why you had to rotate the coils for an M-S output if only to transform their output to a straight L-R? (*)
The point for making an M-S source is to be able to get an adjustable (selectable) image width from full mono to expanded stereo.
George
(*) OK you also gave me something to think over, thanks 🙂 (regarding the stereo to mono conversion)
The point for making an M-S source is to be able to get an adjustable (selectable) image width from full mono to expanded stereo.
George
(*) OK you also gave me something to think over, thanks 🙂 (regarding the stereo to mono conversion)
You spend so much time on this forum so I'm guessing you cannot be that busy?
Some of this is because I can! the main reason was to have a lateral only channel, but because I am building a M_S processing chain for normal stereo use I figured should add the capability to reverse on the mono cartridge. Again no expectations of a benefit.
The (L-R) switch on the Apt Holman preamp was a lot of fun to fiddle with. It offered a strong hint that much of the Fleetwood Mac female vocal magic may have been, gasp, studio processing.
I think Holman did the width control very well. I'm looking at whether the next step of putting studio style processing in gives any additional gains and horror reactions 😉
Coming back on a subject that was discussed a few weeks ago, I can report that I was successful in implementing a working LTSpice model of Peter Walkers masterpiece, with great help from Steve.
For those interested, here is a link to the relevant posting.
Quad 63 (and later) Delay Line Inductors
Hans
For those interested, here is a link to the relevant posting.
Quad 63 (and later) Delay Line Inductors
Hans
My friend who had the same QUAD speakers had replaced all the ceramic caps used in the delay line with film types. Then he removed the voltage multiplier and substituted a commercial HV power supply. Seemed to work better... flatter freq response and more accurate sound.
I noticed we have now fallen to 9th in readership here. Is that a new all time low?
THx-RNMarsh
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We made the caps in the delay line from teflon PCB's for the Crosby Quad. I helped richard work out the sizes for the material we were working with. It did seem to make a difference. I also shepherded the regulated supplies. I'm still not sure how important they are. We have much better tools to understand what we were doing now.
All changes done seemed to work well. The freq response was ruler flat... not like what i have seen from others who tested original. he could vary the HV supply and the top end of the freq response would droop with lowered voltage. To more like original roll-off. I have no data on what HV dc value he used etc. he measured and told me but its too long ago and I dont remember. Could have been higher than stock? We were there just to listen to caps and choose most accurate one by listening. BTW we all three came to agree on same cap construction as best. It was a blind test.
THx-RNMarsh
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It would appear that issues of audio fidelity has now been succeeded by other worries, like the Corona virus, where to get toilet paper, etc.
I still worry about making better audio products, most importantly, the missing link in design quality in hi end digital reproduction. So far as I am concerned, the linear part is darn near perfect (if you are willing to spend the resources), and of course, the old recordings of our favorites can't be made much better by their very nature of using old fashioned (and limited) technology in their recording, but I still shudder at the CD presentations, even today, of great stuff from the past. We can do better!
I still worry about making better audio products, most importantly, the missing link in design quality in hi end digital reproduction. So far as I am concerned, the linear part is darn near perfect (if you are willing to spend the resources), and of course, the old recordings of our favorites can't be made much better by their very nature of using old fashioned (and limited) technology in their recording, but I still shudder at the CD presentations, even today, of great stuff from the past. We can do better!
See to that it has a good portion of 2:nd, a bit of compression and pops and cracks 😉 and your are home free 🙂
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Just took a listen on headphones and on speakers.
I am familiar with many of the pieces from so0me of the big name orchestras.
I'd say its very, very well recorded with great stage width and depth. Good also to hear a classical CD where there's plenty of bass. Its probably not as 'organic' as some of the older recordings of the some of the stuff I have (eg Sibelius, Stravinsky, Tchaikovsky, Beethoven) - the sound is a bit more 'etched' (I say that as a compliment).
Orchestra's also pretty good IMV.
Music: 8/10
Recording 8/10
Nice 🙂
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