Which amp to build?

[[email protected]]

Hi,

    I just purchased a set of Ultrasone Pro 900 headphones, rated at 40ohms.  I will need a headphone amp and was thinking of building the Crack model.  The page specifies that the amp is better for higher impedance headphones and that the SEX amp would probable work better.  I was planning on building the Stereomour and the Crack kits, but I am starting to think that the SEX might work better for me.  The stereomour does not have that much higher watt output, so that alone is not reason enough for me to get it.  If I build the SEX, I can also make the Foreplay as my input selection.  Who knows, maybe I can even make the Paramounts at a later time, and those would most likely be great for my low sensitivity speakers (Soliloquy 5.0, 88db).

   My friend has higher sensitivity speakers (90-93db?), so I would like to be able to test the amp I build with his speakers.  However, he is moving out of state this May, so I really want to get something built before then. Here is how I see my to be system:

Option 1:

  Preamp:  current Seduction  (may upgrade to Eros later)
  Speaker Amp:  Stereomour
  Headphone Amp:  Crack

Total cost:  $643+Stereomour (??$900??=$1543 total)

Option 2:

  Preamp:  current Seduction  (may upgrade to Eros later)
  Speaker Amp:  SEX (may upgrade to Paramounts later)
  Headphone Amp:  SEX
  Input selection:  Foreplay with Extended upgrade

Total cost:  $1647

  If I go with option #2 I have a slightly better upgrade path and the SEX might work better with the headphones I got.  Plus, it means I can order the SEX today and get instant satisfaction instead of waiting for the Stereomours.  Also, is it possible that the Stereomour would ship around the beginning of May?  Any input would be appreciated.  Thanks.

--
Pavel Galchenko
[email protected]

[Grainger49]

Pavel,

I vote for option 2.  The Crack is not the best selection for your current headphones.  The FP III is excellent and many have preferred the sound of the SEX with a FP III in front of it.

The option of upgrading to the Paramounts later for speakers is an attractive upgrade path.

But... you should know that the SEX (suggested for 97dBW speakers) with your current speakers will not reach high volume levels, ever!  This is the only drawback of option 2.  And it might still be a drawback with option 1 (the Paramour/Stereomour suggested for 94 dBW or higher). 

You will want to get higher sensitivity speakers.  Even the Paramount is suggested for 93dBW sensitive speakers.

[[email protected]]

I agree that I will eventually need higher sensitivity speakers.  Right now however, my bottle neck is my amp (cheap SS Harmon Kardon) so it is my first route of upgrades.  My current listening environment is pretty small so I think I can live with lower volumes.  Wouldn't the increase in volume levels be pretty negligible in comparison between the SEX and Stereomour?

[Doc B.]

Hi Pavel,

The Crack will run your headphones, but the S.E.X. will probably run them better. You could try 5998s in the Crack instead of the stock 6080. That could lower the output impedance from about 120 ohms to about 70 ohms. But really that is still a little high for 40 ohm headphones. I'd say the S.E.X. then Foreplay III then Stereomour or Paramount would probably be the way to go considering the headphone impedance. One inexpensive intermediate step might be to buy an input switchbox to use with the S.E.X. kit and your different sources, until you are ready to buy the Foreplay III.

[[email protected]]

Thanks for the advice.  What is the probability of the Stereomour being released by May?  I am thinking that in the long run option 2 would be more economical as I can retire the SEX to just a headphone amp.  Also, doesn't the Foreplay have two sets of output RCA's?  Does this mean I can connect both the SEX and eventually Paramounts or other amp?

[Paul Birkeland]

The first set of speakers I ever ran with my Paramour 2A3 amps were Soliloquy 5.0's (with the sweet factory stands).  While a 2A3 wasn't quite enough to run the 5.0's, the 300B-Glow monoblocks I later found did a pretty nice job.  You might consider borrowing an amp before you write off the match entirely.  IIRC, the impedance plot is pretty friendly on the 5.0.

[Doc B.]

What is the probability of the Stereomour being released by May?

We initiated some new project management software last week, and according to what we laid out for Stereomour we hope to be taking pre orders starting April 15 and begin shipping in May. Don't hold me to that because, as they say, s**t happens. But that is what we are shooting for.

[Grainger49]

   .  .  .    What is the probability of the Stereomour being released by May?   .  .  .   Does this mean I can connect both the SEX and eventually Paramounts or other amp?

Pavel, If you haven't bought Bottlehead before you should know that an April 15 preorder may not be in your hands by the first of May.  There is always time eaten up by ordering parts, delivery and assemble the kits.

Yes, the FP III has two pair of outputs and it will drive the SEX and another amplifier. 

[[email protected]]

I have the Seduction which i built, waited about a month to receive....  Well, since I will be getting the foreplay due to the two outputs, I might as well get the SEX for now.  Many thanks for the help, will order SEX tonight!!! 

[Doc B.]

Thanks Pavel!

[Paul Birkeland]

I have the Seduction which i built, waited about a month to receive....  Well, since I will be getting the foreplay due to the two outputs, I might as well get the SEX for now.  Many thanks for the help, will order SEX tonight!!! 

Awesome!  Do post your results/impressions of the SEX amp and the 5.0's.  I think for nearfield listening, you may really like the combo.