J-Curve.

I'm hurt.

okay wise guy, add up the inductance, capacitance and resistance of that cable. i'll wait.

hey, I'm glad it worked so well. Cyanide just stepped into it and got lucky. I wish I was so lucky. Congrats, Cy.

btw, look up my profile. look under cables.

wallijonn: I was only after some experimentation for cheap , so very expensive cable and interconnects were not on my mind , just some general mucking about for cheap.

j-curve: Funny that , your located in Japan , yet you get stuff from aussie shops! I would have though japan has far better quality and a larger quantity of great electronic stuff for DIY'ers. Having travelled to Japan gave me this impression that its a DIY'ers heaven. Anyway i think i might check it out. A few questions first though, How much power does it need (15v+-)? is it expensive? can it be made portable? and what is its basic sonic signature ie: bassy , smooth , peaky in trebble? thanx for showing me this kit.

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Don't worry wallijohn, I am aware that you shouldn't use lumped parameters for radio frequency cable calculations... Got you wound up though, didn't I? Mogami's website is interesting - they've got a little quiz section in there with some tough questions for cable freaks. Did you have a bad experience with another DIY cable before the Mogami?

Cyanide, yes I go DIY crazy whenever I'm back in Oz. The MSCA amp is designed for +/-15V but will run on less, eg. twin 9V batteries or even a split 9V supply if you swap out the TL072 chip for something which will drive closer to the rail voltages. I wouldn't bother taking it portable because I have no complaints with the sound from my MD. I'm a bit of a minimalist when it comes to amplification - something quiet, clean, neutral sounding and low impedance suits me perfectly and the MSCA is exactly that. I don't think of it as having a sonic signature but perhaps that would change if I had a row of amps to compare it to. Given the difference you noticed with the cable change I think you would be very impressed with a low impedance amp to drive your phones. The standard MSCA is 0.8dB down at 20Hz and 20kHz, and flat inbetween. You could extend these limits with a couple of simple component changes. Cost is hardly worth mentioning (less than 20 AUD) but you should factor in a power supply too. Good luck if you give it a go.

J-curve,

nah, you didn't upset me. i figured i'd cut the discussion at the pass before someone started talking about ICs, caps, amps, etc. the last thing we want is the old "i can't tell a difference between cables" flame wars erupting.

I went with Mogami because I was able to procure it in under 100' rolls. I'm still trying to find a local distributor that at least has Belden 1800 and 83393 in stock so that I can see it's lay. if it's too stiff, i can't use for headphone cord. I didn't mind buying the belden 89207 as I was able to split the cost with Gerg. I think I bought the Mogami cable from Markertek. they only sell the Belden 1800 in 100' spools (or was it even more?). why not cardas or equinox? i haven't heard the equinox, and the cardas are spec'd out for 46pf/foot. i don't know if that's in a quad configuration, in which case that would work out to 23 pf/foot. the mogami is spec'd out at 20 - 23pf/ft, so that's what I went with. the belden 1800 is spec'd out at 13pf/ft. the belden 1801-d comes in at 12pf/ft and a .1650" OD (this may work with dual cable entry headphones, instead of a Quad for single cable entry headphones). yes, I'd rather pay under $20 to make my own 10' cable. the cardas quad wire was reasonable at Markertek.

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maybe you can make me one?? gimme a cost

And yes you can get HP890's for crap all (singapore/malaysia)

around $85 AUS

PooJou: well i bought my HP890's from a place in melbourne city called GO Audio (www.goaudio.com.au) for $140 AUD. Where can i find them for $85 AUD? Im sure i will be able to make you a cable , where are you situated in Melbourne? Simply gimmie the length you are after ect... and ill get back to you with prices. Im experimenting with another low cost cable , maybe you might wanna hold off for a while untill i see wich is better and ill build you the better one? Drop me a line at Cyanide05@hotmail.com if you have any other questions , i should reply back in 2 days or so depending on UNI workload.....

j-curve: I was in DSE today and found the kit for $17 AUD. The only reason i didnt buy it on the spot was i didnt really find a decent PSU for it. I was thinking wallwart style but none of them do +\- 15v regulated. Got any recomendations? i know your EQ is powering your amp ,but how else would i be able to power it like a stand alone unit? If you have any circuit diag's that may be usefull plz direct me towards them... thanx again.

Email Sent man

and you can get them for $85 AUS from s'pore - my boss just got some from there

Do you think i could get away with using an old Computer PSU to power it? I know they pump out a steady regulated +\- 12v as opposed to the +\- 15v that the kit reccomends. Computer PSU's are also supposed to be verry stable and have low noise since most computer circuits are quite sensetive to such things. Do you think that this would hurt performance? Also what kind of current is needed to drive this thing to its optimum? thanx in advance

Hi Cyanide,
I've used a computer power supply once for an electronic crossover kit and (by sheer luck) it was clean, but in general it's better to avoid them because their switched-mode circuits can create all kinds of audio and radio frequency hash.
Didn't you spot the Universal Power Supply Kit at tricky Dickys?

Looks like they've cheaped out with half-wave rectification but what would you expect for eight bucks? You could replace the two diodes with a full-wave rectifier. Need an AC plugpack and probably some kind of box, plastic PCB posts, a "DC power socket" (to let the AC in ) etc. etc.
Otherwise I think there were some power supply circuits for the cmoy amp on Headwize.

I measured total current consumption for the amp at 9mA (idle).