Originally Posted by restock
The relevant review is here:
10Audio review with voltage divider suggestions
I built a nice Mogami cable with a voltage divider on one end to connect the amp level outputs to my two JL Audio F112 subs. What works better, amp or line level out, should be debated in the context of the rest of the system:
1. I don't use a crossover and run my main speakers full range. 2. My tube preamp is optimized into 100KOhm loads with a 5KOhm output impedance 3. Even just splitting the signal to the 10KOhm subs causes the sound to deteriorate in my system (even with the subs turned off). My preamp is just not designed for such low loads. End Result: the output from the amp works much better.
If one has a solid state preamp or a preamp that is stable into low impedance loads with an output impedance below 500Ohm, then connecting the sub to the line should work. Note that if you use an amp with 10Kohm and a sub with 10KOhm and if the two outputs are not separately buffered, then the pre sees a load of 5KOhm. In that case you need closer 250Ohm output impedance on the pre to avoid HF rolloff or a loss of dynamics.
I believe the output impedance of my preamp is about 220 ohms. I'm going to hook it up to my pre line outs first and see how it goes.
C2300 (Telefunkin Smooth plates); MC275 (Shuguang Treasure KT88 & Psvane signal); Sonus Faber Cremona Auditor M; JL F112; Clearaudio Concept MC; Oppo BDP-93; Squeezebox Touch; Music Hall dac23.5 (Burson Op amps, Mundorf & Multicaps, Vampire RCA jacks, Amperex White label 6922); Wireworld Silver Electra PC's, IC's, & SC's; HiFi Tuning