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Trying to find out what higher-gain phono preamps are out there (for low-output MC cartridges)?? My Ortofon MC-20 Super has a pretty low (0.25 mV) output - compared to Ortofon's current lines of low-output MC's(0.3 - 0.5 mV). My Vincent PHO-8 drives it ok, but I find myself at roughly half-volume (with my Parasound A21 pushing 400 watts @ 4 ohms), while all my other higher-gain components/inputs obviously require much less "volume knob" to get the same audible levels. It's not a major issue, but if I'm in a position to change phono preamps, I'd like to move to one with higher gain.
Note: I haven't tried the internal phono stage of my Parasound P5 preamp with my current ttable/cartridge combo, but I can't imagine it'll have more gain than the Vincent (Parasound doesn't publish the P5's MC gain).
Thanks,
Jim
Phono preamp - Vincent PHO-8
Cartridge - Ortofon MC-20 Super
Table - VPI Scout
Preamp - Parasound P5
Amp - Parasound A21
Other - Oppo, Monitor Audio, Carver, Harman Kardon, Ariston, Adcom
Follow Ups:
Very nice phono stage with up to 72 dB of gain.
"It's not a major issue, but if I'm in a position to change phono preamps, I'd like to move to one with higher gain."
Make the change and don't look back. Low gain phono preamps and low efficiency speakers have inflexible issues beyond their apparent sound quality, IMO.
Actually, on a conventional continuous volume control the higher the setting of the control the better(assuming you don't run out of volume control setting). The control is a physically linear resistor and it works by positioning itself within the resistor. The lowest volume uses all the resistor(most resistance). The highest setting none. The higher the setting the less resistor is being used and sonically the smaller a series resistor the better.
So if you have enough gain and like the sound, you're fine. This is even true on a discrete control with individual resistors(though they can be higher quality depending on the resistors used) since a volume control, as I implied above works by attenuating the input signal, not by amplifying it.
"The lowest volume uses all the resistor(most resistance). The highest setting none."
This isn't entirely true. If you wire a volume pot conventionally, 100% of the carbon track is in the signal path at all times regardless of the position of the level control. There has been a lot written about this which, if true, would invalidate Ohm's Law.
The position of the volume knob isn't really all that critical. After all, part of its function is to allow for sources with very different voltage levels.
If your noise floor is acceptable and things are sounding good, I wouldn't mess with your setup.
Hi.
audio research REF Phono 2SE they are available discounted because it has been replaced by the REF 3 Phono that came out this January. It's high gain , quiet & sounds sublime.
Mondial
....I have had one for almost 16 years and upgraded it to the latest version. It is the only "pry from my cold dead hands" piece that I own.
Oz
Don't worry about avoiding temptation. As you grow older, it will avoid you.
- Winston Churchill
Before I bought my ARC SP20, I was looking at staying with a separate phono and preamp. My first choice was the Manley Steelhead. Considered one of the best out their with sound and options. They run 4 to 5k used about 7500 new. But second was the K&K. Why, because I like a transformer based gain increase (Which both had). When using my Northstar Phono preamp with Pass X2.5 preamp and a dynavector XX2 .27 output, even though the northstar had 60+db gain, I built the CIN MAG step up transformer. and used the 47K MM input on my phono preamp. Smooth. detailed and slam all in one with those 3440 transformers (I think that's the model number). They were originally deigned for Microphones. They even cover a 25ohm load.
But I must say I love that I don't have all those separates now. Just a full function preamp and amp. with a Cart that matches my preamp.
Jim,
I have quite a few number of LOMC carts, with the MC20 being one of them.
I use the Phonomena phono pre which has plenty of gain for LOMCs.
You can buy new or pick them up used on A'gon or other sites.
best
You have enough gain, I wouldn't bother. Like the other poster said you'll increase the noise floor. Also while the gain isn't stated for the Parasound the s/n ratio is and the Vincent is better.
ET
Edits: 01/23/16
Thanks for the feedback, much appreciated.
Higher gain phono preamps add more noise. It's just the nature of the beast. A lot of people use a stepup transformer (SUT)with a MM preamp to combat this......
For an active gain stage the SNR will be set by its first gain stage. After that you can keep amplifying by adding more gain stages, the SNR will remain the same. What matters is the input noise of that first gain stage.As long as the gain of the first stage is above 3, you can usually pretty much ignore the contribution of the following stages.
Now, adding the transformer changes that, of course.
Edits: 01/24/16 01/24/16
You post, "Higher gain phono preamps add more noise. It's just the nature of the beast."
That statement is not necessarily the case. Note here I am focusing on the "add more noise" portion of your post. Several high quality phono pre-amps with gain at or around 72 dB do not appear to add noise. These phono pre-amps work wonders with LO MC carts having output of .25mV or less.
For example: Pass Labs XP-25; EAR 324 (both of which I have owned);and Boulder 1008 (which I have heard - or more accurately which did not add noise). I am convinced there are others. And with investigation one may find more moderately priced units are equally quiet.
Cheers,
Ian
Agreed, makes sense. Thank you.
I agree that you might want to think about a Step Up Transformer, which takes your signal ads gain and then sends it along to the phono pre of your pre amp. You might want to look at SUTs anyway. They are passive and quite small. I don't have a link for you but it should be easy to find .
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