[takato14]

I need a home amp with extremely high current and gain. I need to drive the Pioneer SE-700 to its maximum potential, and that requires a monstrous amount of current. It also needs a considerable amount of gain; the Audio-GD SA-31 I tried was not capable of getting enough volume. I'm looking for a bargain. It can be balanced, but preferably not since that'd require a recable. Speaker amps are not out of the question but I'd prefer something that I could use with my other headphones as well. 
 
During a meet, a fellow Head-Fier remarked that these are just as, if not MORE difficult to drive than the HE-6. Their sensitivity is very low and their impedance is infinite because they are a capacitive load, not a resistive load. High output impedances can supposedly help because of this, but I'm not sure this is true.
 
So yeah, these things are f-king monsters. 
 
Some have suggested the Lyr, but I'm hearing conflicting arguments, some say its designed around high current but others say its geared more towards voltage.
 
Any advice? Hoping to stay within the <$500 price range or so.
 
Thanks.

 

[takato14]

Bump? 

 

[mikeaj]

I don't know a single thing about these, but if they are highly capacitive then how does that make the impedance infinite?  It just makes it higher at lower frequencies (okay, very high or "infinite" if testing at 0 Hz or DC, which is not of interest).  Also, if the impedance is high in the range of interest, that means lower current.
 
Is see that 100 dB (SPL presumably) / 3 V is listed for them, 0.1 uF capacitance.  As a basic model, if you just assume they're an ideal capacitor (no idea how off they are from this, but they have to be some if they are accepting any power), magnitude of impedance from that would be 1 / (2 * pi * f * C) with C = 0.1 * 10^-6 and f being the frequency in Hz.  So about 80000 ohms at 20 Hz and 80 ohms at 20 kHz?  
 
What you would need to be careful of is that some amps may be highly unstable and start to oscillate when driving these.  I think.  I don't know which amps would be incredibly stable.  Not something with a whole lot of feedback and excessive bandwidth.
 
 
Why not just use a speaker amp?

 

[kramer5150]

I'm pretty sure those were designed to be powered off a speaker amp, through a junction box / transform device... Like how the koss electrostats of the same era.  I dont think a 1-5 watt headphone amp, or even a similar low wattage speaker amp has enough power for those.
 
EDIT....
These look like they were designed for use with the BIG/HUGE japanese pioneer solid state receivers of the era.
Some google foo turned up this:
 
http://www.audiokarma.org/forums/showthread.php?t=326928
 
 
That massive orthodynamic roundup thread has some info too
 
http://www.head-fi.org/t/111193/orthodynamic-roundup/17805#post_7713212
 
http://www.head-fi.org/t/111193/orthodynamic-roundup/17805#post_7713217
 
http://cdn.head-fi.org/3/32/32f0703a_PioneerJB-21headphonebox-E.jpeg
 
https://encrypted-tbn3.gstatic.com/images?q=tbn:ANd9GcQZ6RnL9uPKqtM0ShQSndJ-tO8PmUDImhnNws1RB6EDSHFRvY5doA
 

 

[kramer5150]

Quote:

I don't know a single thing about these, but if they are highly capacitive then how does that make the impedance infinite?  It just makes it higher at lower frequencies (okay, very high or "infinite" if testing at 0 Hz or DC, which is not of interest).  Also, if the impedance is high in the range of interest, that means lower current.
 
Is see that 100 dB (SPL presumably) / 3 V is listed for them, 0.1 uF capacitance.  As a basic model, if you just assume they're an ideal capacitor (no idea how off they are from this, but they have to be some if they are accepting any power), magnitude of impedance from that would be 1 / (2 * pi * f * C) with C = 0.1 * 10^-6 and f being the frequency in Hz.  So about 80000 ohms at 20 Hz and 80 ohms at 20 kHz?  
 
What you would need to be careful of is that some amps may be highly unstable and start to oscillate when driving these.  I think.  I don't know which amps would be incredibly stable.  Not something with a whole lot of feedback and excessive bandwidth.
 
 
Why not just use a speaker amp?

^ Ditto this... most speaker and headphone amps are not advertised as optimal for capacitive, or infinite impedance loads.  Not that they can't do it, its more that they are not marketed for it and have not been tested for use under such conditions.

 

[takato14]

Quote:

I don't know a single thing about these, but if they are highly capacitive then how does that make the impedance infinite?  It just makes it higher at lower frequencies (okay, very high or "infinite" if testing at 0 Hz or DC, which is not of interest).  Also, if the impedance is high in the range of interest, that means lower current.
 
Is see that 100 dB (SPL presumably) / 3 V is listed for them, 0.1 uF capacitance.  As a basic model, if you just assume they're an ideal capacitor (no idea how off they are from this, but they have to be some if they are accepting any power), magnitude of impedance from that would be 1 / (2 * pi * f * C) with C = 0.1 * 10^-6 and f being the frequency in Hz.  So about 80000 ohms at 20 Hz and 80 ohms at 20 kHz?  
 
What you would need to be careful of is that some amps may be highly unstable and start to oscillate when driving these.  I think.  I don't know which amps would be incredibly stable.  Not something with a whole lot of feedback and excessive bandwidth.
 
 
Why not just use a speaker amp?

Ohh, the impedance is a variable. So that's why the multimeter reads as infinite when testing these. That's pretty interesting. It also explains why piezoelectrics are incapable of producing bass after a certain point.
 
That scares me a little bit. Did not know this was something to be concerned about. I'll think twice about plugging these into any amp I see at a meet from now on.
 
Yeah, these are designed for speaker taps, and I figured that I wouldn't have any hope of powering them any other way. Any suggestions? The drivers can handle up to 30V. 

 

[takato14]

Bump.

 

[aptr91]

usually I'm hesitant to take advice from Z, but this seems like a solid option.