[Daniel Pumphrey]

Hi All!
In a post Some time ago at Headwise I talked about "My" discovery of a new 50 ohm ER4 headphone. After conversations with Don Wilson, the inventor of the ER4 phones it was revealed that this actually had been one of his suggestions when development of the ER4-P was underway. It was decided at Etymotic to develop the P version instead and there are many reasons for this decision. In my own research after this stage I found that the 50 ohm version had serious problems or side effects which can cause transducer distortion when being driven by a dedicated headphone amp. This distortion is driver induced and only seems to show up during extreme transients usually encountered in orchestral music. Tests confirmed driver distortion occurring when powered by even a 40mw source. A standard headphone amp like the cmoy. Amps like those made by Headroom and others can have much more power and can cause this problem to escalate.
It is my opinion now that the ER4-S is the best solution for a system using a separate head amp. The ER4-p is still the very best solution for portable gear in the low power arena. It gets the best out of the portables and is somewhat warmer. Don knows this transducer better than anyone and he certainly knows how to utilize it's qualities with the present products available from Etymotic Research.
Sure my adapter cable costs a little more, but I believe I have done all the proper research to impliment it and also believe I have Don's approval to offer it.
In my posts at Headwise on the ER4-P, S and B and also the newer 50 ohm version which Don calls the X I warned users to avoid attempting to modify there ER4 phones because of difficulty of working with this fragile gear.
That was when I decided to offer a conversion cable to simply convert the ER4-P to S with no danger of harming this phone. In this endeavor I have worked with Don and have his approval for my cable adapter. This is the best solution which does not affect warranty. ( more in another post memory full) Dan

 

[Daniel Pumphrey]

Continued.

I have also experimented with quite a few different types of resistors and have come up with what I consider to be the absolute best in miniaturized space age components. These are also matched to .1% tolerance which may be overkill but certainly can't hurt.
I have also decided to sell this adapter at a price of 40.00 for a time.
My adapter is very well made and appears as a 5 foot extension (or as long as desired)with a gold plated plug 1/4" or 1/8" as ordered by the user. Low resistance oxygen free wire is also used. Making a reliable high quality cable with miniaturized components is not that easy to do.
With this the standard ER4-p can be used as a portable phone and the adapter can be added for amped home listening as an ER4-S. Email me for details. dwpumphery@wilkes.net
Dan

 

[Redwoood]

Hi Dan.
Very interesting posting, indeed.
And a good offer for the ER4-P owners out there (I am not one of them though)

I have one question:

This distortion you were talking about, does it also affect the transducer physically or is it just the sound that suffers?

Bye

Redwoood

 

[dgs]

I have Daniel's adapter, and I love love love it. Check my review of the 4p vs 4s in headphone reviews for details.

 

[Daniel Pumphrey]

Hi Redwood,

The transducer distortion at this level will not harm the drivers. It appears as just enough of a crackle to be bothersome as well as inaccurate. I somewhat remember a statement from Don Wilson about how the drivers are tested and they are subjected to a lot more stress before being approved.
Dan

 

[Redwoood]

So it's safe to test the Etys with different resistance values and then let the sound decide.
Thanks Don.


Bye

Redwoood

 

[d_wilson]

Daniel's adapter is in an extension cable. This way the original cable isn't touched. As stated in other posts modifying the standard cable is not a good idea.

Daniel,
After our discussions I checked and we were using 5% carbon resistors. We switched over to 1% metal film resistors on the ER-4S, and ER-4B.

If anyone has time reply to my new post searching for weak portable devices.

Don Wilson
Etymotic Research

 

[Daniel Pumphrey]

Thanks Don. I have taken a break from audio and return with fresh ideas. Don't change nuthun. If it works, don't break it! Plus, I've grown to really like the ER4-P's, and the bees are gathering dust.
Now I'm R-u-n-n-O-f-t to bed at 5.00 AM. Back to late nights and audio. What a life!
Dan