Facebook post - no more jh13/3a
"By now, most of you have probably heard that JHAudio has decided not to offer the JH3A with the JH13. After much testing and tuning, Jerry has found that the JH16 circuit works best for optimal detail and accuracy out of the amp. The 13 circuit just didn't match up. When the bass knob is turned down, the 16 circuit is +2db of boost at 5oHz. (The passive 13 has a built in boost of 6dB at 50Hz.)
With the amp + 16 combination, you have the ability to have the lows much lower than the 13 and much higher than the 16. This circuit is accurate to 23k, so everyone should be able to set the bass to their preference."