Welcome, Guest. Please Login or Register
Decware Audio Forums
04/17/14 at 02:13:29


Pages: 1
Send Topic Print
Whatís involved in making my Select into a Headph (Read 2274 times)
boead
Ex Member



Whatís involved in making my Select into a Headph
12/24/05 at 14:35:15
 
Whatís involved in making my Select into a Headphone Amp?

My Sennheiserís are 300ohmís, 97db and other headphone Iíll likely own are these AKG 701ís which are 62 ohmís, 105 db.

Iíd like to buy a MLB but Iím not spending $700+ on a headphone amp and then have to tube it to my taste.
My friend has a ASL EL84 SET headphone amp that just sounds really great with some choice tubes. You can have one for $300 used on Audiogon or Ebay easily!

Since my Select wonít be in use till sometime this spring or early summer, Iíd consider converting or doing something so I can use it for my headphones.

Back to top
 
« Last Edit: 12/24/05 at 14:35:55 by bo »  
  IP Logged
dr._sleep
Ex Member



Re: Whatís involved in making my Select into a Hea
Reply #1 - 12/24/05 at 16:04:54
 
Try 100 ohm/2 watt resistor in series on each positive speaker binding posts to +L and +R earphone and a 10 ohm/2 watt resistor paralleled across + to - on each of the  speaker terminals.  Of course ground return of Headphones to - posts

dr._sleep


BINDING POST LEFT
      (+)--------100 ohm----(+) left side headphone (tip)
       \
        10 ohms
         /
        (-)------------------(-) Headphone(sleeve)

BINDING POST RIGHT
        (+)------------100 ohm------(+) Right side headphone
         \                                            (ring)
         10 ohms
           /
         (-)------------------------(-) Headphone (sleeve)
             

the(-) headphone share the same connection on the headphone jack.



Back to top
 
 
  IP Logged
boead
Ex Member



Re: Whatís involved in making my Select into a Hea
Reply #2 - 12/26/05 at 20:51:17
 
I just picked up the following resistors:

10-Ohm, 1 watt Metal-Oxide Resistors
100-Ohm, 1 watt Metal-Oxide Resistors
10-Ohm, 1/2 watt Carbon Composite Resistors
100-Ohm, 1/2 watt Carbon Composite Resistors

Which ones should I try?

RadioShack didn't have any 2 watt Resistors.

Also, are they directional? I didn't think so.

Thanks Doc.
Back to top
 
« Last Edit: 12/26/05 at 20:52:32 by bo »  
  IP Logged
Rap
Ex Member



Re: Whatís involved in making my Select into a Hea
Reply #3 - 12/26/05 at 21:24:41
 
I use to think resistors weren'tīt directional, until I built a passive-pre with the law-faking config. I put one of the 1k resistors different than the other and you could hear it straight away Angry at first I thought the pot was uneven or some in-room reflections were not right, I even tryīd cables and tube-rolling all for nothing Cry then I flipped one of the 1k resistors around and finally both channels had the same gain Smiley I havnīt tryed switching the resistors both around but having them both in the same direction seemsīto have an effect, both were 1kohm metaloxid 1% tolerance and 500ma.
>>mod ment to say 0.5 w not ma>>
Back to top
 
« Last Edit: 12/26/05 at 23:24:13 by Rap »  
  IP Logged
boead
Ex Member



Re: Whatís involved in making my Select into a Hea
Reply #4 - 01/13/06 at 04:01:18
 
http://www.divertech.com/asluhcsignature.html

Just got this device and its very nice so far.

More weight then with the resistors described above, less intolerable detail. Overall smoother presentation.

Gear is all cold tonight, its sounding better as it warms up. I donít think this device is broken in either. Amp hums more then Iíd like.

Will listen for some time and comment back.


Back to top
 
 
  IP Logged
Brian
Ex Member



Re: Whatís involved in making my Select into a Hea
Reply #5 - 01/13/06 at 05:09:23
 
Boead, do you listen to a variety of sources with your headphones?  If it is your cd player only, you might try adding a headphone jack to it's output.  I think it was at Goodcans website that I read of running headphones directly off the cd player.  

An impedance matching transformer might help.  

Back to top
 
 
  IP Logged
boead
Ex Member



Re: Whatís involved in making my Select into a Hea
Reply #6 - 01/13/06 at 11:42:07
 
[quote author=Brian  link=1135438515/0#5 date=1137128963]Boead, do you listen to a variety of sources with your headphones?  If it is your cd player only, you might try adding a headphone jack to it's output.  I think it was at Goodcans website that I read of running headphones directly off the cd player.  

An impedance matching transformer might help.  

[/quote]

Oh no, the headphones need a lot of drive. If I try running my Sennheiserís on a portable player like an iPod its not much louder then a whisper. Even with a hotter output, the drive isnít nearly enough.
Other headphones like the AKG K1000ís actually need a couple of watts to operate at all. Ask Steve D. about the insanity of headphones.

There are many headphones efficient enough to run off portables and sure a line level attenuator will work. Headphones like the Sony 5000ís, almost all Gradosís and some Sennheisers are very efficient but most arenít.

ASL makes this, its what you are talking about.


Back to top
 
 
  IP Logged
Brian
Ex Member



Re: Whatís involved in making my Select into a Hea
Reply #7 - 01/14/06 at 02:50:43
 
I see.
Back to top
 
 
  IP Logged
boaed
Ex Member



Re: Whatís involved in making my Select into a Hea
Reply #8 - 01/23/06 at 07:11:57
 
http://www.divertech.com/asluhcsignature.html

Just got this device and its very nice so far.  

More weight then with the resistors described above, less intolerable detail. Overall smoother presentation.  

Gear is all cold tonight, its sounding better as it warms up. I donít think this device is broken in either. Amp hums more then Iíd like.  

Will listen for some time and comment back.
Back to top
 
 
  IP Logged
Pages: 1
Send Topic Print