[pansixt]

I have used my McIntosh C28 SS preamp for years with the same TT and cart and same amp and speakers.
Recently I picked up an unused NAD C162 SS preamp for temp duty while I decide to rebuild the C28 or switch to a tube preamp (most likely).
It seems that I have to run the volume control on the NAD @ the 3 o'clock position when using the phono stage to achieve the same volume as I did @ 12 o'clock on the Mac.
Can there be that much difference in gain from one phono stage to the other?
I haven't had any recent close contact sonic booms or the equivalent, and other sources seem relatively  normal.
I suppose it could be early onset dementia.
Any takers?
Thanks,
James

[neobop]

Hi,
Hard to guess with the info provided. Moving magnet cartridge? What?
The NAD has 2 sets of outputs. Set #2 can be attenuated up to 12dB. Is there a low level or mute button?

I don't know the gain on the MM input, but the sensitivity seems high enough. The max output of the preamp is > 15V, so I would guess that something is wrong either in the preamp or use/hook up.
neo

[pansixt]

Hi,
Hard to guess with the info provided. Moving magnet cartridge? What?
The NAD has 2 sets of outputs. Set #2 can be attenuated up to 12dB. Is there a low level or mute button?

I don't know the gain on the MM input, but the sensitivity seems high enough. The max output of the preamp is > 15V, so I would guess that something is wrong either in the preamp or use/hook up.
neo

The first place I looked was at the use/hook up thing.
Grado Gold MM. Switch on pre to MM. Set #1 as I'm using only single amp. No low level or mute.
Next I will re-install C28 temporarily (still plays, just noisy phono 1 and 2) to check my headgear.
I was also asking in case my next preamp is line level only and I need a phono stage.
Thanks Neo

[neobop]

James,
I'd guess that you have inefficient speakers. Maybe your amp needs help or new tubes? You didn't mention anything about them but your gain situation seems marginal. I'd think the NAD has at least 40dB of gain on the MM section and another 20dB on the line stage. It could be malfunctioning, but the fact that 12:00 position on the volume control with the Mac is normal, would suggest a scenario like that. My experience with old McIntosh (admittedly limited) would suggest they have gobs of gain.

All of this is guesswork on my part of course. You might want to take a look at your amp. A more powerful amp doesn't necessarily mean it will have more gain, it might just have more headroom. Your post sparked my curiosity with these preamps. The NAD seems like a great bargain like they're famous for. Got a excellent review in TAS and some kind of award. The Mac has rave after rave of testimonials but only after they're rebuilt and all the caps replaced etc. You probably know this, maybe other curious members here might find it interesting. Are you running some kind of 2 watt or low gain amp, or 82dB speakers?
neo

[pansixt]

Neo,
The speakers are PSB Image 4T's. Amp is a stock Dyna ST70.
I thought about amp power as a factor, and also before I posted I looked up the PSB specs. 91db.
They certainly aren't as efficient as the old Cerwin-Vegas that I had for years, or even as the ElectroVoice EV4's that I ran later (and which I still have).
The PSB's are 6 ohm and I've tried them on the 4 and 8 ohm lugs on the ST70. Not a lot of difference.
I was planning on running the PSB's until I can order some Towers from Jim Salk.
He believes the Dyna ST70 will power the SongTowers without difficulty.
But I think I should send the Dyna to Frank first for an upgrade.
Obviously, I should have included more of this info in the original post.
That is why it says "Jr. Member" on my profile. But I am learning thanks to all of you.
James

[BobRex]

I think the first thing you should do is confirm that the gain difference isn't in the line stage.  Unless I missed it, did you try a CD player?  You may have a similar gain in the phono stage, but reduced gain in the line stage.  Also, there is no standard when it comes to volume control tapers.  You may actually have the same gain, just different volume controls.

[pansixt]

there is no standard when it comes to volume control tapers.  You may actually have the same gain, just different volume controls.

Bob,
Good point about the volume controls. I've ran the same outfit for so long that I didn't consider the difference in controls.
My lack of experience in this hobby despite the years, is becoming  apparent even to me.
The answer to your other question is yes. I have tried other sources. Namely AVA Vision DAC with CD player and CATV receiver (digital music channels) and my MR78 FM Tuner and they seemed more aligned with what I have been used to with the C28.
However, I have taken all of this to heart and will experiment more seriously tomorrow.
The lack of attention that my vintage equipment has gotten, also gives me pause.
With all of the kind help I get here, I will figure this (and me) out.
James

[BobRex]

Well, if your other sources are not showing as large a difference, then it probably is the phono stage.  Again, there really is no standard, per se.  Typically a MM stage will have roughly 40dB of gain, but this spec does vary.  It looks like the NAD doesn't have the phono gain of the Mac.