Regarding polarity switches, a point to keep in mind is that when the position of the switch is changed not only is polarity being changed, but the circuit configuration of the component which provides the switch is also being changed. That in itself could conceivably have audible consequences, to a greater or lesser degree depending on the specific design. I would expect that to be unlikely to be an issue in the case of a fully balanced design such as Frank’s ARC line stage, since in a fully balanced design a polarity reversal can be accomplished by simply interchanging two internal connections. However in a design having a single-ended internal signal path changes involving the configuration of active circuitry would probably be necessary.
Oregonpapa 4-13-2017
Here’s another one that I dug out of the vault last night. If you have it, play cut #14 and crank up the volume. Its a good test of a system’s dynamics and the ability to "hold together" while blowing the walls down ... not to mention that its great music a well. :-)
http://www.ebay.com/itm/Antal-Dor-ti-Stravinsky-The-Firebird-etc-Antal-Dorati-CD-5LVG-/302233218987?...
Thanks, Frank. I have that recording, on a CD having a release date of 1991, rather than on the 2004 SACD shown at the link you provided. Very impressive, as I recall, although somehow I haven’t listened to it in quite a few years.
One of my all-time favorite recordings of any work is the LP I have of Stravinsky’s Firebird Suite (as opposed to the complete ballet that is on the recording you referred to), Robert Shaw conducting the Atlanta Symphony Orchestra, on Telarc.
A digitized version of the LP can be found here:
https://archive.org/details/StravinskyTheFirebirdborodinPrinceIgor-Telarc-Vinyl24-bit
And it can be found in CD form at the following link. I see from the review comments, btw, that I’m not alone in liking it. It’s great music, as you indicated about the complete ballet, and the performance by Shaw and the orchestra is excellent as well.
https://www.amazon.com/Stravinsky-Firebird-Borodin-Music-Prince/dp/B000003CSF
And speaking of dynamics, it is absolutely stupendous in that regard, even relative to the exceptional dynamic range that is found on many other early Telarc releases. It so happens that I have on my computer the same Sound Forge audio editing program that is indicated at the archive.org link (above) as having been used to create the digital files that are provided there. Using that program to examine the waveforms in those files I have found that the difference in volume between the notes at the end of the “Berceuse,” at around 17:20, and the concluding note at the end of the work, is around 60 dB! Meaning that the amplifier has to put out around 1,000,000 times as much power to reproduce the concluding note as to reproduce the softest notes. That is consistent, btw, with SPL measurements I have made at my listening position, those being about 105 dB on the concluding note, and less than 50 dB on the softest notes. (My meter can’t measure below 50 dB).
Best regards,
-- Al
