[Eric_C]

SoupRKnowva: I see! Thanks for clearing that up. I really should have paid more attention in Physics, back in the day.

 

[SoupRKnowva]

Quote:

SoupRKnowva: I see! Thanks for clearing that up. I really should have paid more attention in Physics, back in the day.

no a problem, really anytime you have a hard time thinking about how something in our hobby might work, just look at ohms law for guidance  I=V/R and then that P=VxI

 

[qusp]

 
ohm's law isnt all that applicable with drivers, they are not a resistive load, but a reactive complex load. with capacitance, inductance, resistance, impedance (not the same as resistance) and then electromechanical issues as well. closer law is Joule's law, but that leaves a fair bit out too. the lower impedance also means that the same source can usually produce less power across the lower impedance and it takes more current to produce the same power (wattage) over the lower impedance. . the impedance of a set of headphones, especially one as complex as these, varies over frequency, so that the jh13/16 will present a varying load over the range of musical frequencies this is why mostly any useful impedance rating will be given at a certain frequency, otherwise it doesnt really make sense.
 
now that ive 'cleared that up' i'll do what i came here to do, well finally over a year later my jh13 went back to the shop; i was having an issue with one of the bass drivers, or a connector (on the iem not cable) on one ear. while they were there i got them to put the artwork i wanted when i got them on there. they hadnt quite got the printer yet as it had been delayed, so rather than wait i said i would send them back. i never got around to it, because i didnt want to be without them, but since they were going back i got these put on there
 
i'm yet to see a pic, but this is the designs i did up for them. the purple is just the original purple/red transparent colour of the shells. for those who dont recognize it, its the symbols for N-Channel and P-Channel jfets. in a style that's kinda like a tattoo for geeks. the white is an overprint so should 'pop' all my favorite amps of mine for headphones and speaker feature jfets, as with current power amps i'm building too, 
 

 
cant wait to get these back, as they were dysfunctional for a month or  2 before sending thev off and it will have been a month by the time i receive them back, so it should be a honeymoon all over again and i;ve got a new balanced amp module installed in the portabuff, very exciting.

 

[AVU]

What's this about a portable Buffalo II dac/amp???

 

[qusp]

 
 
 
 
thanks Parrots, me too, Zac really was quite patient in letting me describe exactly how i wanted it and indulged me by letting me supply the layered photoshop file he would work from directly (past graphic designer/control freak that i am)
 
AVU
 
just a personal diy thing i've been working on for some time now, not for sale, its more transportable than portable, but no larger than other rigs i have used portable in the past and probably equivalent to the volume/weight of the ipod-solo-dac stacks. the one box is larger than any of those (slightly larger than hifiman too). portable mode is iriver/laptop/ipad->dac/amp.
 
 

Spoiler: too%20far%20off%20topic%20for%20thread%2C%20but%20AVU%20and%20anyone%20interested%20in%20more%20details%20click%20here

 
basically a battery powered buffalo 2 module, but with diy regulated supply fed by A123 2200mah 14vdc LiFePO4 battery pack (this is about half the mass/weight of the build; its a serious battery) the spdif inputs are transformer coupled and then driven by a line driver/comparator for signal conditioning and impedance matching, but not reclocked till the async dac master clock.
 
the amp section and iv stage are one and the same thing, i just removed some of the filters on the output to improve low impedance drive and changed the differential filter/multiloop feedback so that i have slightly more than 1.5x balanced voltage gain (all resistors in signal are smd zfoils and all caps are film), or about 5vrms p2p @ 75-100ma (2+WPC) which is plenty still not ready for primetime viewing and as i said its just a diy thing anyway, no plans to sell them, too much work involved and they would have to cost too much; i also dont have a license agreement with TP.
 
i'm just about ready to get the final reg/control pcb made, after running a slimmed down one i made on perfboard for a little while now. all thats left after that is getting final front and rear panels milled and move forward. only has balanced out and runs the volumite for digital volume
 

 
 
sounds brilliant

 

 

 

 

 

[royhendo]

Got mine back from Fisher today. They sound sublime. With a seal in both ears, the bass is more than adequate, and I'm a bass head. The left monitor isn't 'satisfying' in the same way as the right if that makes sense. The right fit is somehow satisfying in a purely non-sexy kinda way.
 
The sound though - absolutely sublime.

 

[qusp]

what is the tshirt like? i think you know why i ask

 

[royhendo]

Quote:

So you finally got them back, these have done a round the world trip, first to china and now the states.

Yeah mate - they might make another long haul trip too - Kaysen's offered to tweak the fit a little on the left monitor. The right one's just about right I reckon, but the left is a little loose, as if the impressions had shrunk slightly. Lovely musical sound though. I'm spoiled. ACS T1 for complete travel immersion, JH13s for quiet midweek accomodation listening (I work away from my family during the week, every week), and the Etymotic HF2 for my running. I'm all set now really - very happy with that combo. I can now start working on my source. Got an iPad 2 the other week and I'm looking at various options from there.
 
Good memory you've got there Parrots!!
 

 

[TekeRugburn]

 
Absolutely amazing!  Blows away anything I've heard to date.  

 

[TekeRugburn]

^ they were remolds from Fisher hearing

 

[Red Jacket Mike]

I just placed a classified in the FS/Headphones forum; I have a pair of mint, 1 year old JH-13s for sale.  I love the sound, but need something different (and hopefully less expensive) for brisk outdoor walking.  I've discovered that wearing custom IEMs while walking is a bit dangerous, and also noisy (footsteps, etc.).
 
Check these out if you are looking to buy a used pair and have them remolded.  You can see the ad here.

 

[dallan]

An update for those who have followed my footfall issue over the last ten months.  I have found if i pull the back of the earphone out slightly and readjust the tip toward the back of my head(inside my ear) and then get it to sit in that position, still sealed, which is possible, that the footfalls noticeably decrease.  Decrease from 60% music volume to 20%-30% music volume, which is a huge help and almost makes them usable.

 

[adktitan]

I've followed as we ordered ours around the same time. I'm glad they are becoming somewhat usable, but does that cut mustard? They should be as good as your 800, Ed 8, etc (all normal caveats apply, obviously) so have you ever thought of just selling them to someone who would re-shell? Just curious. I know you went through a ton of fittings and work to get them right, but at some point.....

 

[dallan]

They have there uses anyway, on planes when i am on a trip, they are small and easier to deal with than bigger phones.  Also in noisy environments and coffee places nice to have so i am not selling them.  Just prefer walking the dog with the Ed8 or maybe the ESW9 due to noise on 13s.  Seems like when my ear starts shaping to it and then i can readjust the angle that weird way where footfall noise is somewhat tolerable.  One or two people have asked me about the noise because they had it so i thought i would give that solution to try.  Won't be getting a JH3A though due to the problem.  I could see working with an audiologist I may be able to find a solution of sorts in the placement or shape of the stem that goes in the direction that i seem to have to place it and at that point i would consider the upgrade.
 
As far as they sound quality, they are very fluid and have an addictive sound that i find myself craving.  Compared to the ED8 or the HD800........i don't know it is so different but i don't really think that an any iem can compare to those.  On top of that, even being a custom, they are nowhere near as comfortable as full sized i don't think.  Even when you get used to them, it is still something sticking in your ear and pluging them that is somewhat tight.  For me, the sound quality is really good, they have their purpose that other cans can not fulfill but still not sure that i would put them as one of my better audio investments for funds spent.  I think the best so far of over ten thousand dollars worth of equipment (for the money) is probably the HM801 that i only got because i ordered these.

 

[ArrigoShred]

Hey guys, I'm thinking about getting a pair of these and I was wondering if my custom art will be fine on them....
can you guys give some opinions? 


 
thanks~