[sonic_rage]

these things sound great, very in your face. they do have a close resemblance to the SR60. i'll keep burning these in.

very light and comfy, excellent cable and headphone construction.
for 38$ shipped these are hard to beat.

 

[okdivad78]

i just bought one off electronicsbonanza, they haven't come in yet, and i was wondering if the plug was 6.3mm, because on the site it says: Ø 3,5 / 6,3 mm stereo jack (guessing it means not 3.5)
if it is a yes, would a 3.5mm to 6.3mm stereo socket affect the quality of the sound in anyway?

 

[sonic_rage]

the plug is a 1/4 inch, so the bigger type of audio plugs.

 

[facelvega]

adapters don't have much of a noticeable effect on the sound (except maybe really cheap adapters that cut out a channel when they get jostled); the annoying thing about them, especially 6.3>3.5mm adapters, is that they're bulky and get in the way, and unless you get the good one with a bit of cord between the socket and the plug, they put a lot of strain on your source/amp's 3.5 socket.

 

[sonic_rage]

has anyone managed to remove the red foam from the back of the driver??

 

[ericj]

huh?

Yeah, the damping foam comes out. It's two pieces. But why do you ask? it's kinda critical to the sound.

Edit: Why don't you try it - I predict that you'll gain headstage and lose bass extension and treble sparkle.

The foam itself blocks some of the bass backwave. there are two pieces, with a stiff disc of impermeable material between them which bounces some treble back to your ear.

 

[ericj]

Here's a quickie photo of the QP55x internals:



click for big image, but you should get the idea.

The baffle is lined with felt on the ear-facing side, and is vented around the driver. AKG does the same thing with most of their open cans, except they use a thin nonwoven fabric instead of felt.

The foam in the qp55x is very open-celled and passes sound and air easily, but that gray disc is, like i said, impermeable. This is what wualta is calling a 'reflex disc'. high frequency sound bounces off this and goes back toward your head.

Though it doesn't provide much resistance, the foam probably damps the bass backwave at least a little.

 

[sharkz]

Hey ericj, how about a test report of these phones with you TBAAM? I would be very interested and would really appreciate it considering I just picked up one of the $6 imitation ones, but will likely be getting a TBAAM soon. Thanks man.

 

[ericj]

Since it's based on a CMedia chip, $6 sounds about right for a TBAAM. I'd forgotten i was going to do that. I'll dig up my TBAAM later tonight.

 

[ericj]

Ok, my TBAAM drives these about as loud as you could ask to drive 'em. and without audible clipping.

Bass is good, and it should be - the TBAAM is capacitor coupled on the output, with 220uf caps. Into the 100ohm impedance of the QP55x, that means bass doesn't start to roll off until 20hz or so, and there's very little ever recorded that low. Technically the corner frequency is 7hz. A lot of laptops may have only 100uf of output coupling, which moves the corner frequency up to 18hz - which means that audible bass starts to roll off.

 

[sharkz]

Thanks for that. Might have to just pick these up for computer only use, even though I do have a pair of SR60's on order. I didn't think my $6 cheapo USB adapter would make that much difference with a good pair of phones. Then again the only ones I tried were KSC-75's (didn't really pick up much difference, but they are easy to drive anyways just from my headphone jack) and my Sennheiser HD424's (2000 ohm impedance, even this adapter couldn't make them sound any different than comming from the jack, they just need too much power).

 

[facelvega]

Sharkz, if you're feeling adventurous enough to cut into your HD424's cable, I've heard reports that they sound quite good when plugged directly into an amp's speaker outs. You'd need to keep the volume knob rolled down low, of course, but I've always been interested in giving some 414/424 a try that way just to see if the rumors are true.

 

[sharkz]

Facel, might be willing to try this later, but not right now. It would be something to try if I were to shorten the cable/add an 1/8 plug instead of the 1/4" that is on there now. I guess I will consider it for the future. Hopefully when I get my SR60's I will be satisfied for now. At least headphone wise. I will likely get some sort of cheaper amp to start out. Will likely wind up being a PA2V2.

 

[ericj]

There's no reason you couldn't do that, except that the cable is a little bulky.

Easier to buy the grado or sennheiser quarter-inch-to-3.5mm adapter.

 

[sharkz]

I have a Radioshack adapter on it now, but I am on like my third one. Because it sticks out like 3 inches from my laptop, they always bend. It would be nice with not having to worry about the adapter protruding like 3 inches out from my player or laptop. But I agree, the cable is pretty heavy duty. I really need to work on my soldering skills before I tackle this. I have basically no soldering skills at this point.