Counterpoint SA-3.1 and 5.1

Anyone here still using 3.1? I just got one myself and im wondering if i can use the line out  as a regular output like the main out? If im getting it correctly you can use that if the source you’re using has a level or volume output... ?? The line output will bypass the 3.1’s gain mute and balance???

Interesting ^

I have extensive experience with the SA-3.1, having used it for the past 35 years or so.  It can be extremely good if one makes a few improvements.  The raw voltages are very high out of the remote transformer.  It has a LM317T filament regulator and a high voltage zener diode biased series pass transistor for the B+.  The raw voltage to the first capacitor is around 445V which is too close to the rated max 450 volts of the capacitor.  The preamp has very good capacitors for the high voltage section though and I still have one unmodified preamp that is almost 40 years old and the caps are not leaky.  I am in the process of upgrading the sockets to ceramic gold and all the RCA jacks to new shiny gold ones.  My other long time SA 3.1 is greatly modified with twin high voltage regulators, Dynamicaps, Mills & Kiwame resitors, UF4007 rectifier diodes, excellent ELMA input selector switches and tape monitor switch, ALPS black beauty balance and volume control, Black Gate and ELNA cerafine power supply capacitors.  With all these mods that preamp is extremely good and reliable.  I simplified the umbilical cord to/from the remote transformer box by installing a lighted power switch just above the fuse holder and installing an IEC connector so to use a premium power cord.  I also installed a 5 pin connector on the remote box and preamp and use a detachable cord.  I don't like the 120v ac in the preamp and so close to the volume control.  To help make the preamp far more reliable the raw voltages need to be reduced.  I did this by installing a 50W 50W dale resistor that is heat sinked to the bottom of the remote transformer box on the neutral return wire of the primary of the transformer.  With this the voltages in the raw B+ before the regulator is around 375V.  Without reducing the voltages the regulators dissipate too much heat because of the voltage drop across them.  Anyway, the preamp 3.1 and the 5.1 are very close with the only exception of the tube regulator of the 5.1 which is superior to the simple series pass of the 3.1, and Michael Elliott used a variable negative bias supply for the grids on the 5.1 vs. the 4M ohms grid resistors of the 3.1.  If one purchases the 5.1, I would also make similar modifications.  Michael had extensive upgrades for his products during the years up to around 2013 or so.  You can find them on the way back machine link here:http://www.altavistaaudio.com/

Was always intrigued by Counterpoint products. Never could afford at the time. 
   Memory serves as an amazing audio company. 

Oh, I forgot.  Any tube product should have a slow start tube filament supply and a delayed high voltage for the tubes so to prevent cathode stripping of the tubes.  One can do this by switching on the supply for the high voltage after the slow startup of the filaments.  Without a delayed high voltage your tubes won't last long.  Michael Elliott made excellent products but unfortunately they were prone to problems.  With some simple modifications his power amps and preamps are still very high quality and with the extremely expensive products today are a incredible value.  As the dollar continues to drop in value audio products along with everything else will continue to rise.