Something interesting for Mr. Vex to see.

[idiot savant]

saw this when i was cruising through ebay. i took the time to post it because it's the only thing i've seen similar to the imp amp.

http://cgi.ebay.com/Little-Dot-Tube-Headphone-Amplifier-Amp-gr8t-for-HD650_W0QQitemZ5799781675QQcategoryZ40137QQrdZ1QQcmdZViewItem

[Paul Marossy]

Wow, that's cool!  

[ninoman123]

Sounds like some healthy competition. Although...the iMP is so much prettier.

[Hal]

can that drive a low impedance load?

[dubs]

Checkout www.little-tube.com

These are from china.
No they can't drive speakers like the imp.
about $80-100 DHL shipped to U.S.
There's a group buy of them at ipodstudio forums

[travissk]

The seller states that they don't recommend using the amps with Grado headphones... does anyone know what makes the Grado line of headphones different? A couple years back when I had a roommate, I was considering picking up some SR-60's; if I remember right, they're considered some of the best in their price range ($70 new)

[no one ever]

The seller states that they don't recommend using the amps with Grado headphones... does anyone know what makes the Grado line of headphones different? A couple years back when I had a roommate, I was considering picking up some SR-60's; if I remember right, they're considered some of the best in their price range ($70 new)

travis skare? i have you on my aim buddy list for some reason.

[nooneknows]

The seller states that they don't recommend using the amps with Grado headphones... does anyone know what makes the Grado line of headphones different?

I think the higher impedance
M

[amz-fx]

The seller states that they don't recommend using the amps with Grado headphones... does anyone know what makes the Grado line of headphones different? A couple years back when I had a roommate, I was considering picking up some SR-60's; if I remember right, they're considered some of the best in their price range ($70 new)

The Grados are 32 ohm headphones and the Sennheiser are 300 ohms.  The Grados are apparently too much of a load for the little amp.

I have the SR125 Grados and they are terrific!  

regards, Jack

[erix]

Small tube amps and headphones are a natural. Check out Headwize for a few cool projects like:

the Morgan Jones Ear Max Clone and Bruce Bender's 6N1P

ok,
erix

[zachary vex]

this thing is bigger than the iMP and can deliver less than a tenth the power.  it will never drive loudspeakers, being that it's a dedicated headphone amp with a moderately high output impedance.


for your information, here's a list of common headphones and their impedances (the iMP will drive 8 ohm loads):

12 ohms   Sony MDR-F1
24 ohms   Sony MDR-V500 DJ, MDR-V700 DJ, MDR-V900
32 ohms   AKG K-44, K-55, K-66; Beyer DT-231; Grado RS-1, RS-2, SR-40, SR-60, SR-80, SR-125, SR-225, SR-325; Sennheiser HD-500
40 ohms   Beyer DT-131
44 ohms   Fostex T-5
45 ohms   Sony MDR-V600
50 ohms   Fostex T20RP, T40RP
60 ohms   Audio-Technica ATH-M40fs
64 ohms   Sennheiser HD-570
66 ohms   Audio-Technica ATH-D40fs
70 ohms   Fostex T-7; Sony MDR-V6/V7506
75 ohms   AKG K-270s
80 ohms   Beyer DT-250 (“Lo” option)
100 ohms   AKG K-70, K-100, K-301
120 ohms   AKG K-401, K-501; Sennheiser HD-590
250 ohms   Beyer DT-150, DT-250 (“Hi” option), DT-831
300 ohms   Sennheiser HD580-1, HD-600, HD-650
600 ohms   AKG K-141M, K-240M; Beyer DT-770pro, DT-990pro