A bit of Black Box fever...

[Gromit]

These are the speakers the Italians are putting with the AP10.

http://www.klipsch.com/rf-7-ii-floorstanding-speaker

UK price £3000. With a £310 amplifier.

Lorks! Talk about efficient - you could power them with a sparrow's fart. :D

Can't beat the £3k speaker, but I've got a £310 amplifier hooked up with £yikes! worth of speaker cables at the moment.

[Dr Bunsen Honeydew]

I warned you not to fall in love with them

[fafarskid]

'Slight fuzz on piano notes' is not an amplifier fault. It is from recordings. NVA as transparent amplifier shows it. I can hear it sometimes too, but confirmed to be audible on other amplifier also.

[Dr Bunsen Honeydew]

That was also my thought initially and I doubted the customers. I went to France to hear the amp and even brought the CD and amp back with me that was doing it. It didn't do it here. I still had doubts but Gromit has good ears that I trust and if it happened with him then it exists. The only thing it can be is induced instability, but what is inducing it in a couple of locations and not hundreds or even thousands of others is a mystery. Anyway I am not going to go into the cure as it is nobody's business and I am not here to teach people amplifier design, but none of the NVA principles have been broken in the cure.

Yes I have heard it on recordings, probably again instability but induced in the studio or something physically buzzing on the piano. But as you say then it does it on all amps.

[Dr Bunsen Honeydew]

You can create a similar effect by using high-ish capacitance speaker cable, or twisting the speaker cables together.

[Gromit]

'Slight fuzz on piano notes' is not an amplifier fault. It is from recordings. NVA as transparent amplifier shows it. I can hear it sometimes too, but confirmed to be audible on other amplifier also.

This is most definitely a hardware issue, unfortunately, but the AP10 & AP20 here now have had the fix applied and are significantly better. The fuzz isn't confined to piano, it's noticeable on saxophone, male voice and clarinet to name a few.

I am planning on taking a couple of the amps round to my in-laws' house this week to check if this is a local issue. This is purely to put my mind at rest more than anything. Our mains isn't great here as we live in a small village and short power cuts aren't unknown.

[jammy395]

I was going to mention if it could possibly be a dirty main's problem....?
My AP10 is sweet as a nut (Dug out some piano works to check).

[Gromit]

I was going to mention if it could possibly be a dirty main's problem....?
My AP10 is sweet as a nut (Dug out some piano works to check).

It's certainly one thing to rule out here, will know when I get the kit round to the olds' place.

An AG500 may well be worth investing in perhaps.

[Dr Bunsen Honeydew]

The guy in France bought an AG1500, it didn't solve it.

I would prefer if the speculations stopped, now I have the cure I will work out the cause. As I said it is instability or RF pick up. It could also be earth related. But leave it with me when I have sussed it I will tell you.

I really do not want this thread to become focused on it as it has occurred *3* times out of hundreds if not thousands of installations.

[selby]

Completely unrelated but I love that PL-71...it's such a damn handsome deck.