Hi Arniesb. Your - and other recent comments - have prompted me to finally give my own experience with the T1 (Gen1).
From widely varying reports on these Beyers, it would appear to me that these particular headphones do (as with the HD800 it seems!) benefit greatly from being fortunate enough when matching to 'sympathetic' gear downstream. As for being "hard to drive" (not your statement lol!), I myself find that a bit hard to understand. I have plugged mine into various tube amps besides my LittleDot MKIV SE; Feliks-Audio Elise and Euforia... plus a few SS amps, an ibasso DX90 and my Hugo2 DAC/AMP...and all had no trouble whatsoever in driving them with ease.
As for the 'treble spike' issue, once again, I have never experienced it such as to be
overly troublesome. There have been the odd occasions, however, when excessively bright recordings have indeed sounded a bit harsh, but one cannot really blame the T1s for not 'softening' them down enough lol!!
Equally,
some SS amplification can also heighten any brightness in recordings of course. Which is why many folks do recommend tube amps for 'helping' these Beyers...although not all tubes (or the amps themselves!) can be relied upon to 'warm' things up - as I have found over years of rolling many different types of tubes in my three amps. Even with tube amps, the T1s often need other factors in place before they can perform to their absolute best. What I personally have found recently is that they respond well to good upgrades in any and all other elements of the system, from mains power conditioning/filtering, through better media source, to DAC...(my own being an AirlinkTransformers Balanced AC Mains/Advanced Filter ASF3000; Naim UnitiCore server/CD ripper/internal SSD + ext USB media player, and Hugo2...feeding my F-A Euforia). At each stage of upgrade, my T1s performed better across the board, with bass and treble benefiting especially.
What has in fact surprised me most, however (in conjunction with these other upgrades, no doubt!), is the leap in their performance from replacing my (pure silver) interconnects with Neotech single crystal UPOCC silver-wired cable that I terminated myself...and to which I added some UPOCC copper wire. My T1s have never sounded so smooth, but without any loss whatsoever of detail, clarity, or impact - the exact opposite, in fact. Soundstage also is more 3-dimensional still, with even better focus and imaging...approaching the famed HD 800.
As a final 'extreme' experiment - given these effects on T1 performance - I first changed the RCA plugs used on the interconnects to much better ones, with further noticeable improvement...in tonal range and clarity especially. Then I decided to go
ultra extreme and follow the mantra : 'the best connector is
no connector' and take the cable direct to the signal wires
inside the amp, and direct to the DAC's socket via a modified plug such that the wires make direct contact...hence
no plugs, and one set of sockets bypassed completely. All I can say (apart from "am I mad?!) is that I wasn't prepared for the resultant sound...my T1s literally sounded almost like different cans - to my ears, a hybrid T1/HD800, but with a fuller sound even than either on their own, and the sweetest, detailed treble imaginable...
from Beyer T1s!! Not to mention phenomenal bass extension/detail/control/impact...and mids to die for...and even more holographic presentation...etc. etc.
Obviously, one cannot expect folks to perhaps go to such extremes, but hopefully this gives some idea of just what these headphones are truly capable of...and gives credence to the saying : "fortune favours the brave"!! And hopefully won't attract too much derision from those who have never even attempted to trial such things lol!
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