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JLM Baby Animal Mic Pre kits building info below and Reviews can be found here
BA PCB (Baby Animal ) below. PCB is 36mm (1.4") x 120mm (4.7")
BAD PCB (Baby Animal Dual) below.
Links to some of the full Forum threads
The terminal blocks have tongue and grooves which lock them together on there sides. So 2 x 2 way can make the 4way and 3 x 3 way can make the 9way. If you don't join them together they will sit uneven on the PCB.
Note and Errata on BA & BAD:
BA PCB with the date 09/07 has 2 x 0.1uF caps marked on it only one needs to be fitted. One of the 0.1uF is where CL was on the old BA PCB but is not CL. There is no CL position on the PCB so the CL cap needs to be mounted under the PCB across RL on this version of the PCB.
Normal 8 pin DIP IC sockets for OPA2604AP & NE5532AP etc can be left on the PCB if PCB pins are used for the JLM99V
|Power supply||Opamp fitted to baby animal PCB||* 48v phantom power regulator||# 33v to 47v opamp regulator|
|voltage||* zener||* 10k||* BD681||# zener||# 10k||# BD681|
|62v||Hybrid, OPA2604, 990C, 992 , 993||47v||FITTED||FITTED||47v||FITTED||FITTED|
|62v||2520, 1731, LM833||47v||FITTED||FITTED||33v||FITTED||FITTED|
|48v||JLM99v, Hybrid, OPA2604, 990C, 992 , 993||NF||NF||NF||NF||NF||NF|
|48v||2520, 1731, LM833||NF||NF||NF||33v||FITTED||FITTED|
|When regulators are not fitted a wire strap is needed between the BD681 Emitter (E on PCB) and Collector (BD681 centre pad)|
If you can not open the PDF's below you will need Acrobat reader 7.0.
Input Transformers the BABY Animal PCB can take directly are
|Transformer||Ratio||Jumper||Transformer Gain||RL Fixed Impedance||CL Fixed
|RL Variable impedance||CL Variable Impedance||RZ||CZ||RPAD||RG||Total Gain|
|JLM14||1:4||NF||12dB||10k||220pF||2k2 + 50k pot||390 to 440pF||NF||NF||120R||68R||61dB|
|OEP262A3C||1:6.45||LOW||17dB||27k||220pF||10k + 100k pot||390 to 440pF||NF||NF||120R||68R||66dB|
|OEP262A3C||1:12.9||HIGH||23dB||100k||220pF||not tested||390 to 440pF||NF||NF||120R||68R||72dB|
|LL1538 & XL||1:2.5||LOW||9dB||100k||220pF||3.9k + 50k pot||390 to 440pF||NF||NF||120R||68R||57dB|
|LL1538 & XL||1:5||HIGH||15dB||100k||220pF||15k + 100k pot||390 to 440pF||NF||NF||120R||68R||64dB|
|LL1578 & XL||1:5||LOW||15dB||100k||220pF||15k + 100k pot||390 to 440pF||NF||NF||120R||68R||64dB|
|LL1578 & XL||1:10||HIGH||21dB||220k||220pF||60k + 200k pot||390 to 440pF||NF||NF||120R||68R||70dB|
|To load the input for 50ohm mics (150ohm load) use low ratio parts but fit ratio jumpers as HIGH NF = Not Fitted to PCB|
|To make CL = 440pF all BA kits now have 2 x 220pF (One 220pF can be fitted to CL and the other to CZ with a wire link across RZ.|
Total gain is for dip8 dual opamp IC's and 1.1" opamps with 1:2 output transformer. If using 1.1" opamps with no output transformers minus 6dB from total shown.
Adjusting voltage of large 52v 2.2A power supply
Just for clarity
The only thing the Deane Jensen 990 Design and mine share is the pinout configuration. The JLM99V is more like a Neve Class A Preamp on major Steroids. It is a pure path device with the signal path only travelling through three transistor junctions. It has gain limited to about 60dB with no feedback applied. When setup right the THD with feedback is 0.005% at normal operating levels heading up to 0.5% 2nd Harmonic as its output swing reaches closer to the power rails. It has a 1v DC offset on the output due to the -input of the opamp being an emitter input. It runs best on +/-34v but can run on +/-24v.
JLM111DC Output transformer.
Can be used for Neve LO1166 or API 2503 type DIY projects. The transformer is DC gapped and has 3 identical 150ohm windings that are trifilar wound. So can use as 1:1:1 or 1:2 or 2:1 applications. It is physically the same size as the LO1166 except the the top terminal plate is narrower so it will fit on its side in 1 unit high racks which have a 38mm internal height. Each winding has its connections opposite each other and one side is marked Red+ and the other Yellow-.