As I know Republic of Kazakhstan now.

Additionally unexpectedly and accidentally found a forum thread about the formation and creation of Perun headphones at famous Ukrainian forum... https://hi-fidelity-forum.com/forum/thread-116792.html

Any amp. IMHO they are like 009 or easier to drive.

Just recieved my 2nd pair at 12.01.2023 - Perun Live Sound. There's no problems with KGST amp and (original) Perun SS amp with disbalance at all (236VAC from wall). Waiting for KGSSHV Carbon to test x9000 and two Perun pairs. Will let you know.

At my KGST amplifier, Stax x9000 is harder to drive vs Perun rock headphones and Peruns must be charged for 15 mins before listening after long period of discharge/ disconnection from an amp. For the same position of volume knob, Perun headphones are louder than x9000 for about 15-20% (11...

Congrats! I owned KGBH too. Now at KGST and with x9000 and Perun it is enough (yet?) for me ).

You need 'classic' electrostatic amp, converters are highly 'not recommended' at all. I used Stax T1W with my pair and all was perfect with balance and volume knob was at 13:00 o'clock max. As I can figure - Perun headphones are very sencentive to bias voltage regarding to their large membranes...

400 gramms w/o cable.

I doubt they was scratched originally...It is 'big thanks' to Customs examination. Yesterday I dived into vinyl (facepalm) 1st time with Perun headphones...Later it was unsleepy night))))

I think you can write at site at order form and you will recieve all info and explanations IMHO.

'Quadrun' is a slang name of Perun Rock 2-way driven version coz it has 4 drivers (Quad) - 2 at each cup: 1st huge for bass and mids and 2nd for trebles.

I just got my own pair of Perun 'Quadrun' rock version at early june of 2022. They really rocks! I've compared them to Stax x9000 I own from february. I was shoked but Perun has much more natural sound signature, deeper and mercury bass and they are has much more reverberations. I've discovered...

I can recommend as a very decent person and seller!

Now I'm at Israel (till 02 june 2022) with pair of Perun Rock version. I will test Stax x9000 and new Perun Rock 2022 in a couple of days.