here is my list from best to worse for driving X9K, i have owned all amps and tested them with different sources 1.Stax SRM-212S modified with AN Kaisei NP + linear power supply ultra low noise and with some other modifications 2. Energon amp with KT-66 tubes 3. Novem 4.High-amp sirius v9...

Modified Stax srm-212s for X9K and it sounds just great. Capacitors Audio Note Kaisei non polar 22u-350V. Removed resistors R1 and R2. Removed C1 and C2 caps. Tried different filter capacitors on C7 and C8 but ended up not to use any filter capacitors. Power supply DC ultra -low noise linear...

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Coming from Stax world ( X9K) to planars and Hifiman new HE1K stealth. Have avoided to listen to planars because they don't present the liquidity like a excellent electrostatic headphone. First i had on loan a topping D90 amp to test how it matches with the new stealth , big disappoitment...

EnVogue DaCapo left, made in Italy, sold in Germany on name EnVogue some 25 years ago but these are rebuild in Netherlands to the lastest specifications, probably don't find it anywhere, very rare price back then some 12K. Right Energon electrostatic amp, custom made in Hungary, is probably...

Try to research how far you can get X9K. Feed the Energon amp straight with tube preamp and result is some sort of of out of body experience , the music appears to come from nowhere, at least you have the feeling that certainly not from the phones. The X9K is smooth like butter and musical as...

Use Stax X9K with Energon and Hifiman HE-1000 stealth with the other tube combo

i had to do this....... wooden Novem

that's exactly right ,colored amps is asked when driving X9K to it's best, to make critical listening with Novem the amp must be warmed up at least 20 minutes. I use Judy Spotheim passive preamp infront of Novem, have turned volume on max and adjust it through it. I can make straight comparisons...

A feature wich not often comes to mind if listening only with one amp. The Novem amp fit's the X9K in that sense that it presents a "right size" to X9K. My other tube amp, double mono design, presents a huge soundstage much more than Novem but the problem comes here. If you listen from Tidal...

....and Novem is a well build and very clean inside

I wasn't sure about Novem first but realized later that it needs "burn in " in time at least 2-3 months as many other tube amps do. The tubes are critical, i would avoid the JJ ecc99 gold pin output tube and use the normal silver pin instead. Input tubes are also critical, NOS Mullard has been...

Always coming back to Novem amp/Mjölnir Audio with NOS Mullard input tubes , sounds really nice with X9K, looks good after i switched a silver colored potentiometer to it. Warm tube sound but still presents all details

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My personal experience is that it is easier with dynamic amps to make a combo sound good, electrostatic amps are almost individual matches, you buy an amp particularly for X9K or 009. It's rare that you have a good match with two different phone models. When you buy for instance X9K you have to...

I have never compared dynamic and electrostatic amps, two topics wich i strictly keep separated.

I have played a lot with 845 and 2A3 amps and i prefer Egoista 2A3 over 845 it's more musical. If you like a 845 amp shine you need old united electronics 845 tubes, even old RCA 845 tubes doesn't come close. New 845 tubes are garbage how to make an amp sound good with those. Egoista 845 has...

Agree, x9k can deep fast bass, if you don’t get it look at your source. If somebody is interested to know, the Energon amp uses KT66 tubes

The amp is not yet commercial, it's called VAmp-ET/Energon and it has great synergy/perfect match with X9K, p2p wiring inside, double mono design, complitely new electric circuit approach/ design to drive electrostatic headphones, super musical . I have owned Mjölnir Carbon and other stax mafia...

I was curious to compare because the first unit wich i had and my friend had a listen to it and he dicided to buy one because it sounded excellent. When he got he's own unit he's first reaction was it doesn't sound identical, the soundstage was different. To my ears the latest unit sounds just...

Call me crazy i don't care but here are my personal findings with my ears. Comparing 3 units of X9K phones S/N 10xx, 11xx, last close to 14xx. Note that differences are only in region of 1-3%. The differences are in soundstage and in the area of upper midrange, all have identical bass. 1. unit...

This amp has great synergy with X9K ,i use NOS Siemens tubes ,it’s by far the most musical stax amp

Here you see the medium dense felt, the thickness you can calculate by the picture. The size of the 0-ring can be calculated by the diameter of the inner driver case. The widht of the felt is about 1cm and when you look at the driver from outside it should be as in picture. The 009 case has...

The 007 and hybrid 007/009 are different projects. Nice work you have done with 007 it should sound much better than standard version. The hybrid version needs damping rings, i used a felt 0-ring to stabilise the driver and the driver is wedged in place, a method wich was used by france company...