NAD PP2 Phono Preamp Upgrade

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Jump to Latest
H

henkel

Member
Joined 2005
One more question for Algar emi, if you're still looking.

Regarding your R05,R06 resistor change on the MC input stage of the NAD PP-2, could you confirm with me which are the MM equavelent to the above 2 resistors?

Is it R31,R32 or is it R29,R30?

Also need to know the value of the original resistor?

Thanks.
 
H

henkel

Member
Joined 2005
Just to answer my own ealier Q,

the input resistors for the NAD PP-2 is R31,R32 on the phono board. FYI to the others who may find this thread helpfull.

I am still in the process of finnishing more mods to the NAD and will post them up once I complete evaluation and satisfied with the sound it gives me.
 
F

filholder

Member
Joined 2005
Funnily enough havent been reading this thread at all but today i took apart my pp2 and noticed the ne5532 opamp in it. I thought for about half a second then wipped it out and stuck in a OPA2134 i had kicking around. I also replace the power smoothing caps after the reg with some 1000uf panasonic FM. Just those two changes made a bloody huge differnce to mine. Been listening to records all afternoon, maybe give it a whirl worked for me.

Phil Holder
 
H

havar

Member
Joined 2007
Algar_emi said:
Henkel I got your answer. The gain is set by R37 (Left Channel), and R28 (Right). The default value is 249R, gain of about 34dB

If you parallel a resistor of this value with R37 or R38 you'll have these gains:

R38 or R37 // 220R = Gain 40dB
// 100R = Gain 45dB

You should use metal film 1% resistor, otherwise you can have left and right gain missmatch.
Solder the resistor on the bottom of the PCB, much easier.

Try that and let me know.
The image is showing where R37 and 38 are located.

Have fun.
Click to expand...


Howdy!
If I need to get a higher gain in the MC section, is there any similar solution available..?

I have a low output MC pick-up, and I use a passive pre-amp, so the gain is simply to low. As the pick-up is of the 0.4mV type, the gain in the PP2 (58~60db gain) gives between 318mV and 400mV out from the PP2. Here I need more than a 1000mV, so the gain should be at least 70db, or even more.

Is this possible to arrange, or do I have to buy anoter RIAA?
 
H

henkel

Member
Joined 2005
havar,

I no longer have the NAD with me but,

I believe changing the same R37 & R38 resistors as per pointed out to me earlier will solve your lack of gain problem, as the resistor are at the gainstage, not the MM or MC input area.

However, as I have found out, getting too high a gain may result in a certain glare or courseness noticeable.

Do try it out.
 
W

Werner

Member
Joined 2002
Here's a rough diagram for the PP2 in MC mode:

album_pic.php


http://www.vinylengine.com/phpBB2/album_pic.php?pic_id=6458&full=true
 
H

havar

Member
Joined 2007
Werner said:
Would be surprised if the Kenwood didn't totally trash the NAD.

The PP2's design is not very inspiring ...
Click to expand...

Yup, I'm afraid you're quite right... Then we have to add the WAF, and then the Kenwood is the big looser... :rolleyes:

The problem is that as I'm using a passive pre from Dynamic Precision, I have to "loop" the phono-signal through the Kenwood to get enough gain, and then it is two pre-amps, and two volume-controls in my setup.

I have about a thousand different releases on vinyl, and it would be a pitty not to play them now and then... Of course I ought to buy a new, and really high-end RIAA-stage. This will be my next aim I guess. But first of all I must find a RIAA which gives me at least 68-70db gain, and that's not to easy, I'm afraid... :(

The RIAA in the Kenwood is really good, but I'd rather get away with only one pre-amp. Actually the L-1000C is a pretty good pre-amp. I've removed lots of unnessecary caps, bypassed and changed other for better qality, as well as replaced a lot of opamps (16-17 pieces...) with units from BB. Not to forget; I've wuzzed around in the PSU as well. All in all this made the Kenwood play very well in my fully balanced (XLR) setup. The Kenwood is as you may/may not know, a fully balanced unit. The only preamp I've tested better, is my Dynamic Precision BPC 7.3. With that said, I must underline that there's lots of units out there, which I have not testet!
 
A

Annon

Member
Joined 2011
I recently got a PP2 second hand without a power supply. I picked up a 24v power supply from radio shack, which causes the power light to come on, but the audio output is just humming.

The audio input is not able to be heard at all, it sounds exactly the same if the turntable isn't even hooked up.

Any ideas what the problem could be? Does this sound like a power supply issue, or is the PP2 busted?

Thanks!
 
N

norgesjam

Member
Joined 2019
Hi guys I have a PP2E and a PP-3 , but the later came without original power supply. as I had one home that can be set from 2vdc to 24vdc, I put it on 12v and plugged it, unfortunately, I reverted the polarity -/+ in the middle of the , so no sound comes out, and can't even say if it was working before. strangely the green led is on, when I put the dc. Can anyone advise if there is a fuse? as I cant see any usual fuse with glass and string inside...and if its worth to repair. thanks. (ps, its about the pp3)
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Top Bottom