@jetson
The most significant adverse consequence of running the Herron or the ARC phono stages that were mentioned into your Ayre amp is, IMO, likely to be weakness in the deep bass region. That is because the output impedance of those phono stages at deep bass frequencies undoubtedly rises to much higher values than the nominal spec, due to their use of a coupling capacitor at their outputs. (The impedance of a capacitor increases as frequency decreases).
Also, I see that the speakers you’re planning to purchase this year are spec’d at +/- 2 db down to 24 Hz, so their excellent deep bass extension is likely to make the issue more apparent than it would be with many other speakers.
I seem to recall a report here some time ago of reasonably good results running the Herron into 30K, although I don’t recall what speakers were being used. But I haven’t ever seen any reports about the Herron’s performance into an impedance as low as 20K. Also, I don’t know what the value (the number of microFarads) is of the coupling capacitor that is used in the design, which would help to quantify the issue.
I suspect that a phone call or email to Keith Herron would be the best way of determining if the issue is something you would want to live with until you obtain a new preamp. I’m sure he will give you a sincere and well-founded opinion.
A few months ago, btw, Keith did explicitly recommend to another member that his phono stage not be used in conjunction with a 10K load, citing the likelihood of compromised dynamics. See one of the posts by Uberwaltz dated 4-2-2018 in this thread:
https://forum.audiogon.com/discussions/ugraditus-is-calling-again-phono-stage?page=2
Good luck. Regards,
-- Al
The most significant adverse consequence of running the Herron or the ARC phono stages that were mentioned into your Ayre amp is, IMO, likely to be weakness in the deep bass region. That is because the output impedance of those phono stages at deep bass frequencies undoubtedly rises to much higher values than the nominal spec, due to their use of a coupling capacitor at their outputs. (The impedance of a capacitor increases as frequency decreases).
Also, I see that the speakers you’re planning to purchase this year are spec’d at +/- 2 db down to 24 Hz, so their excellent deep bass extension is likely to make the issue more apparent than it would be with many other speakers.
I seem to recall a report here some time ago of reasonably good results running the Herron into 30K, although I don’t recall what speakers were being used. But I haven’t ever seen any reports about the Herron’s performance into an impedance as low as 20K. Also, I don’t know what the value (the number of microFarads) is of the coupling capacitor that is used in the design, which would help to quantify the issue.
I suspect that a phone call or email to Keith Herron would be the best way of determining if the issue is something you would want to live with until you obtain a new preamp. I’m sure he will give you a sincere and well-founded opinion.
A few months ago, btw, Keith did explicitly recommend to another member that his phono stage not be used in conjunction with a 10K load, citing the likelihood of compromised dynamics. See one of the posts by Uberwaltz dated 4-2-2018 in this thread:
https://forum.audiogon.com/discussions/ugraditus-is-calling-again-phono-stage?page=2
Good luck. Regards,
-- Al