Biased 4406 networks

[Uncle Paul]

http://jblproservice.com/pdf/Studio%...ries/4311B.pdf

C1 becomes 2 16 uF in series
C2 becomes 2 6 uF in series

At the junction of each cap pair is a pull down resistor. Each resistor connects to the positive terminal of the 9 v battery. The negative terminal of the 9 v battery connects to ground

[Rusnzha]

C1 becomes 2 16 uF in series
C2 becomes 2 6 uF in series

At the junction of each cap pair is a pull down resistor. Each resistor connects to the positive terminal of the 9 v battery. The negative terminal of the 9 v battery connects to ground

Thanks for the info, it made my day. You made it so simple I can't help wondering why I didn't figure it out myself. I put bypass caps on them a while ago and was amazed with the improvement. I'm still trying to find out just how good these old JBLs can get.

[Rusnzha]

Originally written by Uncle Paul

C1 becomes 2 16 uF in series
C2 becomes 2 6 uF in series

At the junction of each cap pair is a pull down resistor. Each resistor connects to the positive terminal of the 9 v battery. The negative terminal of the 9 v battery connects to ground

I got all the parts together and built them this weekend. I used Solen 16ufd and 6.2ufd main caps and bypassed them with AudioCap .01 ufd and 2.7 Megohm pull down resistors. I had to tweek the Lpads afterward due to some added brightness in the mids. Everything on them seemed to tighten up including the low end. I thought I was crazy since the low end goes straight through but a friend who was familiar with the L100 agreed that the bass tightened up. We did some more tweeking and wound up with the mids at -1/2 and the highs at 0. I turned my bass and treble up just a hair past flat. Damn, they sounded good! Now, they give my main system (6.1 surround with Studio Series 412s, 38s, Center and 2241H) a real run for the money on some things if you're not in the sweet spot.

Uncle Paul, thanks for making it simple. I wanted to do this for a while and you helped me get it worked out so I was comfortable to get the stuff and do it. I am enjoying my L100s more than ever.

[Uncle Paul]

Happy to help and glad you got such pleasing results!

[brettMc]

Happy to help and glad you got such pleasing results!

Hi all,

i posted to this forum back in 2012 my first post.

i just love my 4406's for me they perform better in my room than my 4312's.

i am dying to hear one you pros out there help take them to the next level. Please let me know if anyone is interested in helping me reach 4406 audio nirvana!

i reside in LA if that makes it any easier....

many thanks!

brett

[Malefoda]

Both charge-coupled and bypassed, OEM PCB. Tiny MKPs from industry (Arcotronics) with some creative lead bending and voilà.
I feel it's like we've moved from a cheap, slow, boring and muddy CD player for a more alive-cleaner-detailled one without any harshness.
Had those cheap MKPs, dozens of K71-4 Polystyrene and L-pad resistors (Mills); to be honest can't tell the ratio on SQ improvement related to parts quality or CC...
In the end it sounds very good to me: very good these 4406!

About voltages regarding to 9V:
http://www.diyaudio.com/forums/multi...kers-need.html