Atma-Sphere S 30 & Zero Autotransformer Boxes


Does anyone out there have experience with using the Atma-Sphere S 30 integrated tube amplifier with speakers that have low sensitivity -- around 84? It looks like the best option for solving the impedance problem is Paul Speltz's Zero Autotransformer boxes.
sabai

Showing 3 responses by sabai

Wilsynet and Clio09,
John Atkinson's measurements of my Joseph Audio Pulsars stated: "However, as indicated by its plot of impedance magnitude and electrical phase against frequency (fig.1), the Pulsar is an easy load for the partnering amplifier to drive. Not only is the phase angle relatively low, the impedance remains above 8 ohms for most of the audioband, dropping below that value only in the lower midrange, to reach a minimum magnitude of 6.5 ohms at 210Hz."

Here is a link to those measurements:

http://www.stereophile.com/content/joseph-audio-pulsar-loudspeaker-measurements
Wilsynet and Clio09,
Thank you for your informative posts. The speakers are 8 ohm with an impedance curve no lower than 6.5 ohms. Do you think the Zero Autotransformer will solve the problem? I do not listen to unreasonably loud music since my hearing is very sensitive. I am uncomfortable with the high volume levels that others are often able to tolerate.
Clio09,
Thanks for your informative post -- greatly appreciated. This confirms Ralph's feeling and my own. That's what I was planning to do -- try the S-30 on its own and then add the Zero boxes if needed. I am looking for a pair on the used market. Regarding those spikes, it might help that I have REL sub.

Thank you very much for your kind offer. I would like to be able to take you up on it but I live in Asia which is a big problem when trying to put together a high end system. If I want to audition good equipment it means flying to Hong Kong, Bangkok or Singapore. I get to audition equipment infrequently and end up flying blind most of the time. I have had phenomenal success but have ended up selling off a lot of equipment over the years.