Phono cartridge matching please help

No, 5mV is ok with a 46dB phonostage. It will be too loud because your SP9 has 21dB gain in its linestage, not because the phonostage has too much gain.

Say you have the Shiit Mani set to 42dB gain - about right for the 2M Red - and you feed that into a line input on your SP9, you will still be sending the signal through the SP9's linestage with its 21dB gain giving you 63dB in total.

Here's the SP9 mkIII manual:
http://www.audioresearch.com/ContentsFiles/SP9MKIII Manual.pdf
On page six it tells you how to reduce the gain of the linestage by 6dB. Unfortunately, that still gives you 15dB gain. However, as heyraz rightly says, the gain of the CD input is 12dB lower than the other line inputs, so you could use that and the volume control would be a bit more user-friendly.

Still, the SP9 is (was?) a pretty expensive preamp with an onboard phonostage. It seems a shame to abandon the onboard phonostage and use a pretty cheap external phonostage instead. A pair of 20dB attenuators at the power amp's input sockets would be my preferred option.
I agree with you, it would be a shame to not use the phono section. If I did get the attenuators, I should be good to go with nearly any MM cartridge? And would they be necessary with the Denon 110?
 
So are you saying that in searching for a cartridge, the output voltage should calculate near to 68 in the KAB calculator, since the gain of the phono plus line stage is effectively 68?
What were they thinking with this arrangement? It's so limiting. Is that how it works in all preamps? 48bd gain is not accurate because you have to add in the line stage gain? I would think it would be separate, ie: line inputs get a small boost and phono gets more to match the other inputs. Am I missing something?
 
So are you saying that in searching for a cartridge, the output voltage should calculate near to 68 in the KAB calculator, since the gain of the phono plus line stage is effectively 68?
No, I'm saying the phonostage has 48dB gain and that's the figure to use with the KAB calculator. Actually, I recommend you don't become too focused on the figures the KAB calculator gives you - there is some latitude. Very roughly, you're looking for about 40dB gain for a typical MM (5mV) and 60dB gain for a typical LOMC (0.5mV).

What were they thinking with this arrangement? It's so limiting. Is that how it works in all preamps?
I think linestage preamps should have about 10dB maximum gain when using typical power amps. More gain does allow you to handle sources with lower outputs but restricts the usable range on the volume control. I shouldn't complain because I've sold literally thousands of pairs of attenuators to cure the problem of amps with too much gain.
More gain in the linestage preamp is fine if the power amp has less gain (lower input sensitivity). Maybe Audio Research power amps have lower input sensitivity than most.

48bd gain is not accurate because you have to add in the line stage gain?
It's the same for any external phonostage being fed into a linestage preamp - the phonostage gain is added to the linestage gain. The gain of the phonostage is there to boost/equalize the signal from the cartridge so it's about the same as all the "line level" sources such as CD players, streamers etc. which also go into the linestage.
 
No, 5mV is ok with a 46dB phonostage. It will be too loud because your SP9 has 21dB gain in its linestage, not because the phonostage has too much gain.

Say you have the Shiit Mani set to 42dB gain - about right for the 2M Red - and you feed that into a line input on your SP9, you will still be sending the signal through the SP9's linestage with its 21dB gain giving you 63dB in total.

Here's the SP9 mkIII manual:
http://www.audioresearch.com/ContentsFiles/SP9MKIII Manual.pdf
On page six it tells you how to reduce the gain of the linestage by 6dB. Unfortunately, that still gives you 15dB gain. However, as heyraz rightly says, the gain of the CD input is 12dB lower than the other line inputs, so you could use that and the volume control would be a bit more user-friendly.

Still, the SP9 is (was?) a pretty expensive preamp with an onboard phonostage. It seems a shame to abandon the onboard phonostage and use a pretty cheap external phonostage instead. A pair of 20dB attenuators at the power amp's input sockets would be my preferred option.
Ok, I'm willing to give your products a try. You suggest -20 standard attenuators based on all we've discussed. As I understand it, they will bring the gain down for the entire system. This is preferable than just reducing the phono with the other type. I should notice more usable gain and improved signal to noise ratio. On the website it says -20 is for extreme cases. Remember, I'm not keeping the 2M Red in the system, and will probably go with the Denon 110. Does that change your recommendation?
 
Remember, I'm not keeping the 2M Red in the system, and will probably go with the Denon 110. Does that change your recommendation?
Maybe 20dB would be on the high side if you're using a Denon 110, but you have to consider what else you might be using the preamp for. Do you use a CD player or a streamer or anything like that? You haven't mentioned any other source being too loud.
I suggest you get the DL-110 if that's what you want and try it first, then make a judgement as to how much attenuation you need between the preamp and power amp. Maybe 10dB will be enough attenuation. That usually puts the volume control about 2 hours farther round the clock face.
 
Maybe 20dB would be on the high side if you're using a Denon 110, but you have to consider what else you might be using the preamp for. Do you use a CD player or a streamer or anything like that? You haven't mentioned any other source being too loud.
I suggest you get the DL-110 if that's what you want and try it first, then make a judgement as to how much attenuation you need between the preamp and power amp. Maybe 10dB will be enough attenuation. That usually puts the volume control about 2 hours farther round the clock face.
Ok that's what I'm going to do. I have a CD player and it seemed a bit too low. I steam Spotify from iPhone via Bluetooth so that volume is infinitely asjustable.
Last night I switched out the Perreauxfor the Odyssey Stratos in Khartago. I read a thread in AudioCircle discussing excess gain with AR, Odyssey and other systems and your product was mentioned. I'm not alone with this issue as you know.
 
Maybe 20dB would be on the high side if you're using a Denon 110, but you have to consider what else you might be using the preamp for. Do you use a CD player or a streamer or anything like that? You haven't mentioned any other source being too loud.
I suggest you get the DL-110 if that's what you want and try it first, then make a judgement as to how much attenuation you need between the preamp and power amp. Maybe 10dB will be enough attenuation. That usually puts the volume control about 2 hours farther round the clock face.
I don't have a lot of space behind the Odyssey amp, as it's quite deep and I've got thick input cables bending right near the wall. Would I be able to place the "source" resistors at the preamp main outs instead of at the inputs of the amp?
 
Maybe 20dB would be on the high side if you're using a Denon 110, but you have to consider what else you might be using the preamp for. Do you use a CD player or a streamer or anything like that? You haven't mentioned any other source being too loud.
I suggest you get the DL-110 if that's what you want and try it first, then make a judgement as to how much attenuation you need between the preamp and power amp. Maybe 10dB will be enough attenuation. That usually puts the volume control about 2 hours farther round the clock face.
I tried a CD player on the CD input and I couldn't get past 12 noon. Forget trying it in another line input. It was unbearably loud. But once the overall gain is reduced with an attenuator, I'm hoping all sources will fall between 9-3 o'clock. At least I have a choice of inputs for CD, one with 12db reduction.
 
Really, the phonostage is a moving magnet phonostage - simple as that.
And yet, mine served quite well for about 12 years using two mid output MCs - a Shinon Red Boron and a VPI version of the Dynavector DV-20 each with about 1 mV of output. Changing loading Z did require soldering a different resistor to a special "turret" on the board.

The SP9 did have more gain than the GamuT CD-1 I was using at the time required especially since it's output was 4V. I built attenuators using DACT stepped units which worked quite well and improved image width since channel separation was a touch weak on the 9 series. Still have that around someplace. I chose a cabinet that looks like a Mark Levinson JC-2. Used the pre for phono only.

Today, I use an SP20 with similar gain, albeit split more optimally for line level sources. Fortunately, it has switchable resistance that can be changed on the fly with the remote which helped me determine the optimum setting (500 ohms). I find the cartridge output and preamp gain to be a Goldilocks combination.
 
Would I be able to place the "source" resistors at the preamp main outs instead of at the inputs of the amp?
Yes "source" attenuators used on the preamp outputs are an alternative to using regular attenuators on the power amp's inputs. In your case it seems they would be more convenient.
 
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