Hello Curt,
It is nice to hear that everything is progressing well. When Purist 2.0 upgrade is available, please contact me. The recent upgrade of amps with high gain and sensitivity cause the audible hissing when putting the ear close to the speakers. I am glad to hear the new revision lower the noise level even further.
I hope the pink noise generator is staying. I have been using it to burn in my new amps and tube preamp. I really like it.
I know there is slight voltage dropped during the pre ...
Hello Howard,
It's nice to hear from you. Thanks for your kind words and for your input.
I too find the PN generator quite useful. I like using it to help setup the listening room and for finding the best loudspeaker positions. It is especially useful in bi/tri-amp systems for setting driver levels. It will remain in the Purist 2.0 design. Hopefully more people will learn what it can do for them.
That slight voltage shift (about 1/2V) happens when you turn the Purist off, not on. The DC offset servo cap is discharging. This is not a problem in most systems as most people turn off the amps first then the sources and then the preamp (IRDs recommended sequence). Adding circuitry to stop this would be adding circuitry in the signal path and could adversely effect the sound.
As for amplifier manufacturers that tell you to leave their amps on all the time (which IRD doesn't recommend) they should then offer a mute switch to protect the amplifier's input from natural input spikes such as power mains wiring induced spikes, lightning induced spikes, and yes, even other equipment's on-off transients.
It is IRDs position that an open amplifier input (on all the time) is an accident waiting to happen. That accident might not just be fried amplifiers it could also extend to include blown drivers in a very expensive loudspeaker system.
Caution and safety with a large investment such as in high-end audio is never a bad thing. IRD knows there are many schools of thought and respects most of them, please understand that this is just IRDs opinion on this issue. Food for thought.
The Purist doesn't have a volume level pot. It has a volume level “ladder step attenuator” which will remain in the Purist 2.0 revision. We believe the ladder step attenuator is far superior to a pot.
The input selector and gain selector switches will remain the same with a few added positions on the gain selector to select the new available lower gains.