GAIN Mic Pre / Makeup Amp Kit

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JOETONE
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Re: GAIN Mic Pre / Makeup Amp Kit

Post by JOETONE »

I little messy on this test unit from larger parts I had in stock, but I checked every connection, I must one missing something.

Thanks for the help, I get one right, I can do the other 5...
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JOETONE
Posts: 13
Joined: Tue Jan 24, 2023 11:01 am

Re: GAIN Mic Pre / Makeup Amp Kit

Post by JOETONE »

RLOAD is 600Ω, what the EQ wants to see.

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Joe Malone
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Re: GAIN Mic Pre / Makeup Amp Kit

Post by Joe Malone »

I would ohm test the tracks back to the 470uF to one end of RGain and the other end of RGain to GAIN terminal. Encase a pad has been broken off a track.

As the soldering is a bit messy to see I would clean the pcb with alcohol and a toothbrush as well.
Joe :-)
JLM Audio
Capturing Audio without Injury

JOETONE
Posts: 13
Joined: Tue Jan 24, 2023 11:01 am

Re: GAIN Mic Pre / Makeup Amp Kit

Post by JOETONE »

Ok! So I bought multiple GAIN PCB, so I did up another from scratch and works correctly.
Thanks for your help with my 1st DIY.

***One question regarding connecting power to (2) units.

Series or parallel from your: 48v 25w 520mA Switch Mode Power Supply. ??

Thanks!

Joe

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Joe Malone
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Re: GAIN Mic Pre / Makeup Amp Kit

Post by Joe Malone »

JOETONE wrote:
Tue Apr 04, 2023 3:22 am
Ok! So I bought multiple GAIN PCB, so I did up another from scratch and works correctly.
Thanks for your help with my 1st DIY.

***One question regarding connecting power to (2) units.

Series or parallel from your: 48v 25w 520mA Switch Mode Power Supply. ??

Thanks!

Joe
You can only run multiple gains on 48v smps in parallel
Joe :-)
JLM Audio
Capturing Audio without Injury

JOETONE
Posts: 13
Joined: Tue Jan 24, 2023 11:01 am

Re: GAIN Mic Pre / Makeup Amp Kit

Post by JOETONE »

Hi Joe,

I'm planning on feeding (2) GAIN kits from (2) Jensen JT-16-A for MIC pre input.
https://www.jensen-transformers.com/wp- ... -16-a1.pdf

Can you tell me what to fit for CZ,RZ,RLoad,CLoad?

Thanks,

Joe

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Joe Malone
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Re: GAIN Mic Pre / Makeup Amp Kit

Post by Joe Malone »

JOETONE wrote:
Mon May 08, 2023 10:20 am
Hi Joe,

I'm planning on feeding (2) GAIN kits from (2) Jensen JT-16-A for MIC pre input.
https://www.jensen-transformers.com/wp- ... -16-a1.pdf

Can you tell me what to fit for CZ,RZ,RLoad,CLoad?

Thanks,

Joe
From the datasheet you linked to
Rload is 6k19 = 6.2k
Cload is not needed (leave blank)
RZobel is 4k53 =4.53k
CZobel is 620pF
Joe :-)
JLM Audio
Capturing Audio without Injury

JOETONE
Posts: 13
Joined: Tue Jan 24, 2023 11:01 am

Re: GAIN Mic Pre / Makeup Amp Kit

Post by JOETONE »

Joe sorry to bother you again.

Jensen here in the US has no supply, backordered for long time on the JT-16-A.

Could you let me know same info, RLoad, RZobel, CZobel for this model recommended substitute.
https://www.jensen-transformers.com/wp- ... 15K-e1.pdf

Thanks,

Joe

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Joe Malone
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Re: GAIN Mic Pre / Makeup Amp Kit

Post by Joe Malone »

JOETONE wrote:
Wed May 10, 2023 5:10 am
Joe sorry to bother you again.

Jensen here in the US has no supply, backordered for long time on the JT-16-A.

Could you let me know same info, RLoad, RZobel, CZobel for this model recommended substitute.
https://www.jensen-transformers.com/wp- ... 15K-e1.pdf

Thanks,

Joe
JT-115k only needs Rload of 150k. No RZobel or CZobel or Cload are needed so are left blank.
Joe :-)
JLM Audio
Capturing Audio without Injury

JOETONE
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Re: GAIN Mic Pre / Makeup Amp Kit

Post by JOETONE »

THANK YOU - you have been incredibly helpful. Much appreciated.

JOETONE
Posts: 13
Joined: Tue Jan 24, 2023 11:01 am

Re: GAIN Mic Pre / Makeup Amp Kit

Post by JOETONE »

Thanks for your help!

Finished up this rack of 2 Fairchild EQ's with your gain PCB's for make up gain, sound great., kinda like a LANG.
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Re: GAIN Mic Pre / Makeup Amp Kit

Post by Joe Malone »

JOETONE wrote:
Fri Dec 22, 2023 3:30 am
Thanks for your help!

Finished up this rack of 2 Fairchild EQ's with your gain PCB's for make up gain, sound great., kinda like a LANG.
Cool neat build. Great to hear you got it all working 8) :D
Joe :-)
JLM Audio
Capturing Audio without Injury

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