AudioCircle

Audio/Video Gear and Systems => Owner's Circles => Vapor Audio => Topic started by: planet10 on 30 Dec 2017, 10:12 pm

Title: Impedance of the Vapor Audio Nimbus?
Post by: planet10 on 30 Dec 2017, 10:12 pm

Hi,

The question of use of a SET with the Nimbus recently arose, and no impedance curve could be found to see how well matched a high output impedance SET would be with this speaker.

I wonder if someone has this measured curve?

dave

Title: Re: Impedance of the Vapor Audio Nimbus?
Post by: gab on 30 Dec 2017, 10:39 pm

Quote from: planet10 on 30 Dec 2017, 10:12 pm

Hi,

The question of use of a SET with the Nimbus recently arose, and no impedance curve could be found to see how well matched a high output impedance SET would be with this speaker.

I wonder if someone has this measured curve?

dave

Dave - PM Pete Schumacher. If he can't help you, he will know who can

http://www.audiocircle.com/index.php?action=profile;u=4797

gab

Title: Re: Impedance of the Vapor Audio Nimbus?
Post by: planet10 on 30 Dec 2017, 11:02 pm

Thanx, i will.

dave

Title: Re: Impedance of the Vapor Audio Nimbus?
Post by: Pete Schumacher on 30 Dec 2017, 11:26 pm

The Nimbus impedance curve is not very flat, but that's easily fixed with a compensation network.  If you intend to use a high output impedance (low/no feedback SET) let me know and I'll work up the conjugate network you can place on the output of the amp to flatten the impedance.

Title: Re: Impedance of the Vapor Audio Nimbus?
Post by: planet10 on 30 Dec 2017, 11:45 pm

The system in question is Steve’s of Empirical Audio. You may already have tuned up his XO, but he was batting zero when asked about it — he seemed to lack an understanding of the potential issue.

http://www.diyaudio.com/forums/digital-line-level/314762-dac-blind-test-audible-difference-whatsoever-post5291478.html (there are relevant posts before & after)

I will cross-post your reply so he knows to contact you. Thanx again.

dave

Title: Re: Impedance of the Vapor Audio Nimbus?
Post by: Pete Schumacher on 31 Dec 2017, 12:59 am

Steve's XO is not tweaked for use with no-feedback SETs.  However, the SET he's using has enough feedback that the small impedance swings will be well tolerated.

I am intimately familiar with Steve's SET amp.  I have a pair of the same monoblocks, as well as the schematic.  He's good to go without an impedance conjugate network.

Title: Re: Impedance of the Vapor Audio Nimbus?
Post by: planet10 on 31 Dec 2017, 01:51 am

For those not also following the thread on diyAudio i replied to the same reply Peter put up on diyAudio.

http://www.diyaudio.com/forums/digital-line-level/314762-dac-blind-test-audible-difference-whatsoever-post5292905.html

Thanx again Peter.

dave