Hello guys and gals, I think it's high time that the ALO Studio Six got its impression going. I think there are several of us who either have the amp or are borrowing it (me) and have had enough time with it to begin to give it some thread time.
My take (So far)
I will get the ball rolling by reiterating the few reviews out there that confirm the Studio Six' wonderful capability of driving multiple headphones at the same time. In fact, it seems like it was designed specifically do multiple headphones. Of course, different Ω/sensitivity headphones will vary output volume so that some headphones cannot be used at comfortable volumes. Beyond that, there is power galore. It's funny. ALO have made a number of amps that I consider benchmark in terms of high current to mid/high Ω headphones. The tiny International was one. Studio Six is another.
Obviously you don't buy an SS for earphones but the combo works pretty well. I need a few more days to really firm up my impressions with earphones. In terms of single headphone usage, there simply isn't a headphone too scary for the Six. Typical 'hard to drive' high Ω headphones such as the 600Ω DT880, the T1, HD800, etc., are child's play. Since they aren't current hungry, they generally play well from most high voltage outputs. The Six has a very controlled, very smooth volume pot. I'm fully comfortable using the DT880 at a volume position of 7-8 o'clock. (The Six maxes out at about 5.) At no time during no recording of any genre or any vintage does the Six struggle getting enough current to any of the above headphones even when volume is maxed out. Of course, maxing the Six not only turns your headphones into speakers, but makes them loud enough that even when put in another room, you may want to close the door to preserve your hearing (in the long run).
Is it too much?
Well, no. Headphones with notoriously low sensitivities (I've not tried the K1000 with this) such as HiFiMAN's HE6 and HE500 were probably much of the hardware impetus behind the creation of the Studio Six. They drive perfectly under all conditions. ALO probably shot for 'last home amp you'll ever need' for those headphones and for another favourite, the LCD-2. I don't own the LCD-2, but I borrow one ever time I do amp reviews. Paired to the Six, it shows its power and its grace more completely than with many other amps. Stereo control as well as attack times are right on.
The Six fails to slow down or trundle. It is speedy even when plugged into low Ω portable headphones that usually stymie full-size amps targeted at low sensitivity headphones. Balance is perfect for its target phones. Even super sensitive earphones such as the Sleek Audio CT7/SA7 attain perfect tracking balance at listenable levels. The volume pot is a long-throw pot, so control is pretty much perfect for anything out there. Earphones are probably too sensitive for the Six though. Internal hum is low but audible from portable headphones and earphones.
Proper home headphones of any vintage/variety never ever hum when plugged into the Six.
I will get to depth, noise levels, and imaging a bit later.
Excellent. Studio Six is a proverbial tank in both its materials and quality of build. From the sturdily anchored RCA jacks at the back to the precise alignment of all four 6,3mm headphone jacks and the thick radiating grill on top, SS isn't going anywhere. There is no external hum, no buzz or anything when plugged in, no wobble at any connection, and the valve ports, volume pot, in/out labels are etched into the panels. You can operate this thing in the dark.
It looks great in black (I've not seen a silver version) and it really really drives.
I will post more complete impressions in this thread as well as at Ω as the week gets long. Currently, I've just got impressions there that mirror this thread. If I spot more on the web, I'll put them here, too.
Edited by shigzeo - 8/11/13 at 10:47am