Hi Ian,
Ok I need both boards NA 321 and NA 324.
Can I connect the 20K poti directly to the NA 324 or is a separate board what I need?
Is there a plan where all boards connected?
Regards
Ok I need both boards NA 321 and NA 324.
Can I connect the 20K poti directly to the NA 324 or is a separate board what I need?
Is there a plan where all boards connected?
Regards
Not so fast - look at inside pics of NAC 32,42,62 etc. As I said, those circuits or very similar ones are also on the mother board or main PCB. You will see the 4 and 5 transistor circuits there as discussed. The various plug-in boards are for other inputs - up to 6 on some models, I think. What that means is the various sources can all be connected to a specific, matched level input gain stage which suits the various output levels of a tuner, phono, tape in and tape out etc.- as was normal when the preamp was designed many years ago. The only plug-n boards you see in the NAC42pic are phono preamps.
Now, with digital music servers, many owners never use the preamp for anything more than a single input and volume control, so there is little point in making and fitting extra boards unless you are a vinyl/retro hifi enthusiast.
The are are no schematics or service manuals for complete Naim products - just the few sub-circuits that you can see. If you can't work out how to connect a volume pot between two stages or just by just by looking at the many pics on the net, use the ESP guide to pots and wiring here: Potentiometers (Beginners' Guide to Pots) You would do well to study this site, it's a goldmine of good quality Audio DIY info, resources and study material.
Anyway, no, you don't need a separate board to connect to a pot, just 3 wires for each channel -In, Out, Ground - look at the copper traces on the underside of the board - same thing as wires.
Now, with digital music servers, many owners never use the preamp for anything more than a single input and volume control, so there is little point in making and fitting extra boards unless you are a vinyl/retro hifi enthusiast.
The are are no schematics or service manuals for complete Naim products - just the few sub-circuits that you can see. If you can't work out how to connect a volume pot between two stages or just by just by looking at the many pics on the net, use the ESP guide to pots and wiring here: Potentiometers (Beginners' Guide to Pots) You would do well to study this site, it's a goldmine of good quality Audio DIY info, resources and study material.
Anyway, no, you don't need a separate board to connect to a pot, just 3 wires for each channel -In, Out, Ground - look at the copper traces on the underside of the board - same thing as wires.
Attachments
This is all the Ebay NAC42.5 clone contains on a single board. It has a single input with no switch selection but includes the regulated power supply and a volume control. The control is not shown on this old kit version schematic, but it connects to the input, shown as connector XX1).
As a preamplifier, it's really just NA321 with volume control and is designed to be cheap, so the performance is not likely to be very good because of the circuits being closely packed together with the PSU. There will likely be further low level noise and cross-talk due to non-ideal PCB layout and whatever DIY wiring technique is used.
As a preamplifier, it's really just NA321 with volume control and is designed to be cheap, so the performance is not likely to be very good because of the circuits being closely packed together with the PSU. There will likely be further low level noise and cross-talk due to non-ideal PCB layout and whatever DIY wiring technique is used.
Attachments
Hi
Hope this is the right thread.
I am building a NAP 200 Zero Zone clone, and have decided my next project to be a preamp.
I am considdering a Nac 152XS clone Aldo from Zero Zone: ZeroZone NAC152XS on eBay
Had any of you experience with the NAC152XS?
Or would you suggest another preamp?
My project are intended to be something like:
I plan to use power out from my NAP 200 clone!
This buil is not intended to be 100% Naim, but more like a heavy Naim inspired preamp.
I am planning to use Arduino as controll unit. Input will be controlled via relays and a LCD screen to present settings.
I will also add WiFi and a Webserver to controll the preamp. I have not decided yet but are also considdering WiFi in my power Amp. Then I eg. can monitor temperature!
I am also considdering how to add volume controll. Either a motorized pot or a digital resistor (i think it is Calles)
In V1: there will be 8 analog inputs.
In V2: 6 digital inputs and a DAC are adfærd.
V3 is a RIIA
Looking forward to your comment.
Kind regards,
Thomas
Hope this is the right thread.
I am building a NAP 200 Zero Zone clone, and have decided my next project to be a preamp.
I am considdering a Nac 152XS clone Aldo from Zero Zone: ZeroZone NAC152XS on eBay
Had any of you experience with the NAC152XS?
Or would you suggest another preamp?
My project are intended to be something like:
I plan to use power out from my NAP 200 clone!
This buil is not intended to be 100% Naim, but more like a heavy Naim inspired preamp.
I am planning to use Arduino as controll unit. Input will be controlled via relays and a LCD screen to present settings.
I will also add WiFi and a Webserver to controll the preamp. I have not decided yet but are also considdering WiFi in my power Amp. Then I eg. can monitor temperature!
I am also considdering how to add volume controll. Either a motorized pot or a digital resistor (i think it is Calles)
In V1: there will be 8 analog inputs.
In V2: 6 digital inputs and a DAC are adfærd.
V3 is a RIIA
Looking forward to your comment.
Kind regards,
Thomas
AGND & PGND are not connected directly and only with 47uf cap? Is it work? Is it couse charge/discharge period of 47uf (so preamp close&open)?
NAC42.5,
Make http://www.acoustica.org.uk/ "Recent Gain board" changes and add input filter before pot. I used 4k7&100pf (350khz) only. Pre's HF becames more clear (big change exactly). Now: filters freq. on pre, 350khz&150khz (2k2&470pf (I have good cup for 470pf, Naim's adviced 10k&100p)). On nap140 102khz(4k7&330pf). all cups are polyester or MKS2 or 1kvolt. Naim used 70khz filters, I couldn't test all freq filters 🙂 ref (https://www.hifiaf.com/nait2-recap-guide/):
Note that C5 (or c12 on the schematic) on pre is very important cap. It must be very good kind. I used Elna silmic II.
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