hi all,
i cant really seem to find much info on this..
apart from what it does is that it adds impedance on the output.. forcing player to output higher power giving cleaner signals.. and possibly removes hissing noise from circuits (is it?)

but there are those headphone with very high impedance,
there's also customs, ksc also has impedance modding..
so..

what i'd like to know is.. how does having the adaptor.. or changing the impedance affect the sq, eq, or signature actually?
is higher better or...?
what about impedance matching? what is so significant about matching it? how do i match my player to iem's impedance?

thx in advance for any contributions on this questions..

I've read quite a few posts in head-fi suggesting that an adapter in most cases WILL have a negative impact on SQ, but well... you know, hearsay and head-fi. take it with a pinch of salt.

I don't see how forcing anything to a higher output power creates cleaner signals man...

Impedance matching is usually done at the cable/board level to maximize power transfer. To match the characteristic impedance (Zo).

The ER-4 from Etymotic has an impedence adapter (resistive adapter) that acts in conjunction with the capacitance to form a filter that changes the frequency response of the unit using it.

well i couldnt find much info.. that's one of them that i found.. probably..
anyway if talking about signal attenuation.. if the output is not strong enuff.. there will be some attenuation, or frequency drops..

im hoping someone here (eg: PcWork ) who does have those adapters can give his experience on that..

This post has been edited by DaEMoNteNTAcLe: Mar 11 2010, 04:21 PM

Attenuation doesn't work that way. Attenuation is a fixed function for the most (sometimes frequency dependent)

If you have a level of attenuation, the signal will be attenuated by that level only.

eg; an Attenuation of 1 dB, so if you put 10 dB in, you come out with 9 dB, if you put in 40dB, you come out with 39 dB. Something like that.

Sometimes you also attenuate the noise caused by reflection due impedance mismatch.

I wonder impedance adaptor can stop the hssing sound from my low end sound card.

i have the impedance adapter on hand. u are welcome to have a listen
overall it has different sound shaping effect to different type of driver.

im not sure.. that's one of the thing i wanna try out.

hoping u'd offered.. was considering of getting one from u actually.. but i wanted to be sure first.
anytime ur free to entertain me? i live in bangi so if ur in serdang i can drop by anytime.
thx

I try get one from pc work but he too busy to reply pm.

try and let me know about the results.

will do..
when he's available that is..

One thing is the impedance adapter reduces the damping factor as the impedance is added to the source's side. Might be bad if you had high output impedance DAPs (read that some ipod had 5ohm output). General rule says 10:1 is good enough. Lower damping factor means amp have lower ability to control the diaphragm especially in the bass region. Damping factor is not the same with every frequency too, before and after adding the adapter.

2nd thing is if i'm not mistaken the impedance adapter attenuates different frequency differently, thus results in different sound signature.

I actually have one 36ohm adapter on my hand now.

It's do fix my first problem, hissing sound not longer come out from my earphone.

still need some time to figure out the sound signature that using impedance adapter.

Hope it's will come close with original sound signature

so any news from you using the impedance adapter?

Sorry for bringing up an old thread. But I have low impedance headphone and IEM at the moment (Grado SR60i, Brainwavz M1, and then later a Future Sonics Atrio).

I recently bought a cMoyBB v2.03. As you all know, low impedance demands more current, and my research has proven my slight worry, that low impedance cans/IEMs can damage the amp in time. I am a low volume listener, but just to be safe before I get myself some higher impedance gears, I would like to get an impedance adapter, just to be safe(my friends LOVE volume, wouldn't want them secretly pumping out volume using the amp without one when trying it out. They can be stubborn sometimes).

Would any cheap impedance adapter be good enough? Does it matter?

if they use the amp at high volume, most likely the IEM or more accurately the drivers will be damaged but that will take quite a long period of time. The amp wouldn't be damaged, if it cannot put out the current required, all you will get is clipping on the SQ.

a common use of impedance adapters is to remove ground loops (hissing) that you get when the gain of the amplifier is too high and the impedance of the IEM is too low.

Actually, JDS Labs says because of high current demand of low impedance IEM/headphones, the amp is the one to get damaged.

But my question to JDS Labs have been answered. Apparently, and fortunately damage to the amp this way is very rare, but does happen. Some guy over at head-fi damages his amp by driving it to distortion levels for weeks. It was fried eventually. I don't think I will be doing that......and I don't think I'll lend it to my friends that long, and I guess I just have to be extra careful when they use it.

If I find a dirt cheap one at some electronics store, might as well buy it for the sake of experimentation.

right, thanks for clearing that up!

OT: any first impressions of your JDS cMoy?

Don't have an interconnect yet. Still waiting from wotiyo. Should arrive tomorrow if he sends it today.

I can't wait to try it with my SR-60i.

i can't wait for you to try it out too!

from what i understand, what happens here is, the amp sees less resistance on low impedance headphone, hence current will flow through more...
imagine water flowing through small river (high impedance) vs water flowing through large river (low impedance).

there will be too much current being drawn from the amp, hence amp overloaded.

as for the results of impedance adapter, i dont find it to my liking.
it reduces hiss, but at the same time it lowers high frequency info, making the sound more closed-in, less airy, or in my own way of saying, less natural ambience and decay.
some people actually uses this to get a better definition of bass, dropping hiss (or noise floor) allows more things to be heard, especially low level details.
but higher resistance also will reduce the strength of the sound, too much and u might end up filtering the soft sound altogether.

i think its better to improve the grounding for cutting down hiss, or the power line for more current output. but im not an amp builder, i cant say much.

Yeah, basic physics. Low resistance = High current, low voltage...and vice versa.

I'm not trying to cut down hiss, I'm trying to avoid frying the amp from prolonged usage at high volumes using low impedance outputs.....or how about I just don't lend it to my friends.

I guess if I were to buy one might as well not go crazy with numbers. Anything that can make the total impedance around 50+Ohm would be nice.

This post has been edited by tunertoobe: Jun 30 2011, 10:24 AM

Dont forget to give review for the jds

Sure thing!

Boss, what is the outcome from your test of SR-60i and impedance adapter (what ohm you use?) . Any promising effect in SQ.

Not really.
Did however require a bit more turn of the volume knob. Never notice anything significant. I think the bass was a bit more controlled when it went louder(than comfortable), but I'm not too sure.

Oh, in case you're asking where I got the adapter, a friend of mine lended it to me. I don't know where he got it from. Looks old though. Damn, I even forgot what impedance it was. I used it with the cMoyBB v2.03 with Bass Boost switched on, just FYI.

This post has been edited by tunertoobe: Dec 9 2011, 11:29 AM

Oo, ok. Don't test on your Atrio M5?

Yes...same story. Only this time the bass was.....for any bass head they would say good. For me, it was close to being absurd, almost funny. The amount was ridiculous.

Haha. Should recommend this to bro yuan415. He's been complaining bout his ES7 lack of bass

The amp is excellent for bringing up the bass. The SR60i became the perfect headphone for hard rock.

Perhaps sometimes later maybe I'll commit to impedance adapter test. Don't have any expectation, just curios though

Hehe, sure. Different source, different output will make the result differ greatly. It's really something to read about it, and then experiencing it for yourself.

This post has been edited by tunertoobe: Dec 9 2011, 11:44 AM

I've just tested 75 ohm impedance adapter for a few days.
Test subject:
phone - silver bullet, piano forte II
amp - 3move
The observation:
-Slight addition in bass department. Both silver bullet & piano forte II is not a bass phone, so its ok.
-Clean sound, i like
The price to pay for these: clipping the other part very much, high, middle, you name it. Sound very weird. Don't like it

Lesson I've learned:
-Dynamic and 75 ohm impedance adapter not good paired. 75 ohm is high. May be good if choose lower impedance? Don't know. maybe yes.
-Do not pair with bass phone, the bass will become too overwhelming (tunertoobe)
-75 ohm is good with high clarity BA IEM, originally intended for er4p.

impedance adapter, you meant this?


i've tried looking for it before, no luck so far.
i need it to control gain output for low impedance headphone when paired with amp, such as tubey. any place i could get this?

yupp, more or less the same plug. Got mine from ebay. Locally, you can order from more2teayap.

yup, can order from more2teayap.

hm3 made a good pair with 39 ohm impedance adapter. 75 ohm is no good.