iRIAA preamplifier prototype

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EposLab
Posts: 180
Joined: Wed Jan 23, 2019 3:40 am
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iRIAA preamplifier prototype

Post: # 61031Unread post EposLab
Fri Jul 01, 2022 3:16 pm

It's been a long time I was thinking of building one of these.
I started with a single channel version as my lathe system is Monophonic.

This Prototype features:
- ALPS Input Volume Control
- Accurate iRIAA eq
- 40dB of total gain
- Low Pass Filter for 12kHz & 16kHz
- Fuse protection for the Cutterhead
- Adjustable VU meter for the Cutterhead
- Custom PCB , Mica caps & Dale resistors

Specifications:
- 2x18Vac external PSU
- Maximum Input signal : 2Vp-p @20Hz - 20kHz
- Maximum Output signal : 200mVp-p @20Hz , 2Vp-p @1kHz , 20Vp-p @20kHz
- 1U 19" rack mount
- Grey Wrinkle painted faceplate

I am currently testing it and looking for a way to print on faceplate and back. Sound performance is excellent and soon will make some measurements.
Any recommendation is welcome :-)
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Epos Laboratory Phono Cartridge Retip & Lathe Cuts
http:\\www.eposlab.gr
info@eposlab.gr
IG EposLab (https://www.instagram.com/eposlab/?hl=en)

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emidisc
Posts: 221
Joined: Mon Jun 07, 2010 7:57 pm
Location: lancashire

Re: iRIAA preamplifier prototype

Post: # 61032Unread post emidisc
Sat Jul 02, 2022 1:46 pm

Looking good👍
I have some basic question
1. Presumably for mono you would require 1x iRIAA unit + 1 x PSU unit?
2. For Stereo 2 x iRIAA unit + 1 x PSU unit?
3. Have you got an Approx target Price?

Personally I would be interested in a Mono set-up that could possibly be upgraded to stereo later

Emidisc

User avatar
EposLab
Posts: 180
Joined: Wed Jan 23, 2019 3:40 am
Contact:

Re: iRIAA preamplifier prototype

Post: # 61033Unread post EposLab
Sat Jul 02, 2022 4:13 pm

emidisc wrote:
Sat Jul 02, 2022 1:46 pm
Looking good👍
I have some basic question
1. Presumably for mono you would require 1x iRIAA unit + 1 x PSU unit?
2. For Stereo 2 x iRIAA unit + 1 x PSU unit?
3. Have you got an Approx target Price?

Personally I would be interested in a Mono set-up that could possibly be upgraded to stereo later

Emidisc
Well there are lots of options there! This prototype I built for my needs cause (as of now) I use a single channel , Monophonic lathe system!
For 2 channel system (stereo) can be done by using 2x single channel iraa preamps (2x PSU) or make a stereo preamp in one case using a single PSU.

I am still testing it so this will need some time for it. One thing is for sure : the more I use it , the more I like it :-)
Epos Laboratory Phono Cartridge Retip & Lathe Cuts
http:\\www.eposlab.gr
info@eposlab.gr
IG EposLab (https://www.instagram.com/eposlab/?hl=en)

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