SEX amp 2.1 4/8/16 or 32 ohms?

[Todd R]

Hi,
Just saw the new amp that's coming out. Pretty sure I'll be getting one, but was curious about the output wiring options of 4/8/16 or 32 ohms.
That wouldn't really concern the headphones, it would be more of an option for the speakers you want to use, correct?

 

[mrarroyo]

Could the speaker outs be used to drive the AKG K1000 or the HiFiMAN HE-6 cans? Thanks.

 

[Grainger49]

The speaker outputs are the same tap as the headphone output.  The headphone jack uses a series dropping resistor.  I'm thinking there might be a problem using a different transformer tap for the headphones than the speakers, might be OK. 

Regardless, it is safe changing or eliminating the series resistor at the headphone jack.

 

[Todd R]

So if you have 600 ohm headphones and a 32 ohm pair, what taps would you use so both pair sound good?

 

[Doc B]

You can only wire up one impedance setting at a time. We will have little under-chassis upgrade boards with switches that will allow setting output impedance without having to disconnect anything, but that will still produce only one output impedance at a time. Yes, in general the various taps are for loads that are a the close match, so 4,8 and 16 are primarily for speakers and the oddball phones ( I think there are some IEMs) that are down in that range. For headphones from 32 ohms on up to 600 ohms the 32 ohm tap makes the most sense. I don't know if the K1000s would be driven adequately, but I would try the 32 ohm tap to find out.

 

[Todd R]

Thanks Doc,
Apart from it's other capabilities, would you consider the new SEX amp an upgrade over the Crack/Speedball when using something in the Sennheiser 580/600/650 family?

 

[Doc B]

Here's what I think about the best headphone match to the various amps:

http://www.bottlehead.com/et/whichheadphoneamp.htm