2. amps-preamps
  3. 177022-167303

Threshold Sa3.9e

Hello, is it possible to have the manual of this fantastic amp?
I am particularly worried about the possibility of driving the 3.9e from my Aleph P1.7 preamp in balanced mode, because I have read that the xlr input impedance of the power amp is only 600 ohm while in the P1.7 manual it is recommended to keep the master volume in the position of least attenuation (where it has the highest output impedance!).
I can't find anything on the web........
Thanks,
Stefano

128x128spersanti276

Showing 2 responses by edwyun

Ag insider logo xs@2x
edwyun
244 posts
 

LOL, uploaded the e series manuals a long time ago. Glad to see they are still up in the DIYA site.

Used a 3.9e for about 20 years back in the day. Doubt your Aleph pre will mate well with the 3.9e using XLRs given the pre’s high output impedance relative to the 3.9e’s 600 Ohm input impedance via XLRs. Will sound a bit lacking in bass.

Still, the 3.9e was a great amp.

Ag insider logo xs@2x
edwyun
244 posts
 

You can connect via XLR but flip the switch on the back panel of the 3.9e to RCA. It will work (as if using the higher input impedance on the 3.9e). But I always thought it was not a good idea. I know others that have changed the internal resistor at the inputs to change the value from 600 Ohms.

More to discover