With Verum on my mind I was thinking if I really need a planar headphone or just want to acquire a new tow to play with. The Peak/Volcano was my previous impulse purchase of must have and after several months of rolling everything I could get my hands on, I've got a good grasp of what it can do. The Peak is a Pete Millett hybrid design with the 6SN7 tube as the voltage gain and mosfet output stage. Some say it was built as a preamp first but it's also one hell of an amp. Pros: - dead quiet, not a hum buzz or crack from all my good tubes. When it unmutes the output at startup there is no change in blackness. - low output impedance - small and compact. The Volcano power supply is somewhere else. It might be the best sounding amp per volume - powerful, drives the K1000 and HD250 600ohm with ease at around 1 o clock volume. The HD650M is at 9 - barely gets warm - front power on switch, looking at you schiit - preamp, though I never used it yet - black - one tube to roll - can use ECC32/ECC33 Cons: - it's light, too light you might think it's a 50$ part when you pick it up. Thankfully it's not an issue and I would rather have better internals than a cool heavy chassis. The Peak was bought to replace the LG which failed as a daily amp. It was too big, hotish, two tubes to roll, not enough bass impact. The LG does have better mids in smoothness and detail and a relaxed presentation the peak can't really do. My guess it's the difference between the output stages. Most of my tubes sounded different on these amps. My Peak came with a sticky volume pot, replacing it was not easy as the solder just didn't want to melt properly regardless of the temperature. SQ: This is the big one and hardest to answer. It depends on the tubes and I already had lots of 6SN7 from the Ember/Teton/LG rolling. I'll cover the tubes in a separate post. With the HD650 I settled on the Sylvania 6SN7GT 1952. Other close ones: MELZ,BGRP,ECC32,6SN7W,B65,Ken Rad VT231,Fivre 6SN7,5692. Many more were just average. On the LG I didn't like the sylvania tube, too warm and smoothed out but a perfect synergy with the peak and HD650. -bass, oh lord that bass. Deeper than you would ever expect the HD650 to go, it actually has sub bass, no mid hump and impressive slam. The WA5LE fully kitted, Stratus and LG lag behind the peak in this area. It satisfies the basshead in me quite nicely. I haven't enjoyed The Prodigy/Spitfire like this since my LCD-3 +6db/60Hz days. Very similar to the Stellaris bass but slightly less control and impact. -mids, neutral, no dips or bloat that I can hear from low to upper mid. Extremely resolving similar tonality to the HPA4 but with a hint of warmth. Again similar to the Stellaris but less so. Reminds me of the HE6 mids with a hint of bloom. -highs, extended to the heavens and what sets it apart from the other 6SN7 tubes. Very 3D with distinct sounds coming from all over the place in a big cohesive soundstage. Detail retrieval is off scale, again no dips or peaks that need eq. On some overcrowded songs it may get out of shape where the Teton/Stellaris wouldn't. If I were to compare the amps I've owned: Project Ember---------Trilogy931-------------WA5LE---GSX-MK2---LG--------------------Peak--Stratus--------Teton----Stellaris Bottom line is the Peak hits it out of park on all areas for my preferred sound quality which is HD650 tonality, no mid bass hump, more sub bass, less warmth, bigger soundstage and let the mids and treble scale. Compared to the Teton. One of my absolute favourite tube combos after much rolling on the Teton is 422A/GEC 6AS7G/Sylvania 6SN7GT and since it's the same input tube it's somewhat a fair fight. Both single ended from the Pavane. - Teton has more impact and warmer bass. You might think it's not as extended as the Peak but the warmer bass hides the subbass somewhat. Teton has noticeable better control which translates to better overall rumble. - Teton has romance in mids where the Peak is neutral. It's also smother with more presence. Both feel like front row presentation which I dig. - High end not as extended as the Peak but has better transparency/detail. Slightly bigger 10% soundstage. Layering is about the same and that's saying something. There's no doubt the Teton is coloured, more so than the peak but it's faster,more dynamic and better in every way. It's like adding another volcano in benefits with just the right amount of wetness. I never liked the GEC 6AS7G before, it has an annoying lower treble peak and I mostly prefer the 6080 bottle over it. The 6SN7GT Sylvania has an amazing synergy and fixes those problems for an extremely natural sound where on the Peak it sounds airier. Final thoughts: I payed more for the tubes on the Teton than the Peak itself. It's a true tube rollers dream and so can cater to almost any headphone. If you can find one and have a stash of 6SN7 go for it.