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Author Topic: Smack and IEMs?  (Read 2435 times)

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Offline Jim R.

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Smack and IEMs?
« on: October 12, 2011, 04:04:14 PM »
Hi Dan,

I don't see any specific mention of testing the smack with IEMs, so wondering if you or any of the other guys and gals at the shop have tried this?  I'm mostly concerned about noise on the typically higher sensitivity IEMs, and if it's not an issue, that's great.

Of course I'll give it a try for myself in a couple of days too.

Thanks,

Jim
Jim Rebman -- recovering audiophile

Equitech balanced power; uRendu, USB processor -> Musette DAC -> 5670 tube buffer -> Finale Audio F138 FFX -> Cain and Cain Abbys near-field).

s.e.x. 2.1 under construction.  Want list: Stereomour II

All ICs homemade (speaker and power next)

Offline tdogzthmn

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Re: Smack and IEMs?
« Reply #1 on: October 12, 2011, 04:49:05 PM »
I use my ER4S fairly often with my Crack and get good results.  They are on the higher impedance side for an IEM at 100 ohms and I would hope they sound even better on the Smack!

Offline Doc B.

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Re: Smack and IEMs?
« Reply #2 on: October 12, 2011, 06:48:21 PM »
Hmm, you know what? I didn't think to try my TF10Vs. I'll take them with me to the show and try them out there - might even buy a Westone ES cable for them while I'm there. I find them kind of rolled off on top once you get a good seal, but they are comfortable on those long walks where I fool myself into thinking I'm burning off this world class beer gut I've developed in my old age.
Dan "Doc B." Schmalle
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Bottlehead Corp.

Online Paul Joppa

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Re: Smack and IEMs?
« Reply #3 on: October 12, 2011, 07:01:24 PM »
...  I'm mostly concerned about noise on the typically higher sensitivity IEMs, ...
For high sensitivity phones, you would crank down the impedance, which means a bigger step-down ratio of the output transformer. Lowest is 16 ohms, which is 9dB quieter than the highest 128 ohm impedance setting. If you have even more sensitive phones, you could substitute the OT-2 used in Stereomour and the new SEX 2.1; it has 6dB less output voltage and therefor 6dB less noise.
Paul Joppa

Offline Jim R.

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Re: Smack and IEMs?
« Reply #4 on: October 13, 2011, 06:12:02 AM »
Paul,

My IEMs are 37 ohms, but I can't find a seensitivity rating yet.  Thanks for the idea on the transformers, but I probably wouldn't want to build the amp to suit just one pair of headphones, but with the switching board set on 16 ohms, and the extra series resistance (if I'm remembering that correctly) I'm guessing it will be ok, but I can just see what happens when I'm at the show.

Going to try them on the s.e.x. too.

-- Jim
Jim Rebman -- recovering audiophile

Equitech balanced power; uRendu, USB processor -> Musette DAC -> 5670 tube buffer -> Finale Audio F138 FFX -> Cain and Cain Abbys near-field).

s.e.x. 2.1 under construction.  Want list: Stereomour II

All ICs homemade (speaker and power next)

Offline Todd R

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Re: Smack and IEMs?
« Reply #5 on: October 20, 2011, 12:29:15 AM »
Hey Doc,
Little off topic, but what value is the volume pot in the Smack?
I got a nice Alps pot sitting here doing nothing that I might like to use.
Todd R

Offline Doc B.

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Re: Smack and IEMs?
« Reply #6 on: October 20, 2011, 06:04:10 AM »
100K ohms.
Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.