Phono loudness???

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The "loudness" of my phono output pales in comparison to my CD output. My preamp volume control turned half way on CD is near concert levels; on phono it's listenable but not loud. I have a Project Debut III with an Ortofon OMP 5E cartridge. Would a new cartridge help? If so, what would I be looking for?
 
It's nearly as important to know what your preamp input criteria is.. does it have a phono input? If so what are it's specs. Perhaps you need an independent phono preamp...or it could be a number of things like an impedance mismatch or more.

I just read an overview on you preamp and it claims that the phono gain is adjustable between 40 and 65 db...you may need to check your settings.
 
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Same issue

It's nearly as important to know what your preamp input criteria is.. does it have a phono input? If so what are it's specs. Perhaps you need an independent phono preamp...or it could be a number of things like an impedance mismatch or more.

I just read an overview on you preamp and it claims that the phono gain is adjustable between 40 and 65 db...you may need to check your settings.

Ironically tonight I fired up my 1983 turntable and had the same problem. Oppo BP83SE at 30 is near concert level but turntable maxed out the pre amp at 62 and there was virtually no bass and the sound was bright and very thin.

I have Summits, Sanders power amp and Cary SLP-03 tube pre amp.
TT is 1980 vintage Rega Planar 3 with SME III tone arm. Cartidge is Dynavector but I can't tell which number as it only says Dynavetor on the side. Phono amp (we used to refer to it as a pre-pre amp in the day) is a Marcof II battery operated. I put in two new D batteries.

The SLP-03 does not have a phono input as far as I understand. I used the auxilliary RCA input. I don't know how to measure impedence.

Any suggestions?

Thanks!

J. M.
 
music again,

Your problem is that you have a pre-preamp feeding a line-level preamp, without a phono preamp in the chain, i.e. there is nothing to provide the inverse RIAA equalization required, hence the thin, bright sound and no bass. You need to go out and buy yourself a phono preamp; they run from about $150 to $12K or more.
 
J.M. I believe that unit inverts phase, which may account for the problem.
Even if it does invert phase that is not the problem; a lot of amps invert phase. The problem is definitely the lack of a phono input on his preamp. You cannot run a cartridge into an aux input. A pre-preamp only provides amplification; it does not do the required equalization.
 
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Even if it does invert phase that is not the problem; a lot of amps invert phase. The problem is definitely the lack of a phono input on his preamp. You cannot run a cartridge into an aux input. A pre-preamp only provides amplification; it does not do the required equalization.

Right, I understand. I thought his unit was a phono amp (he did say phono amp), but now I understand it is a pre-preamp only. Good catch Bernard.
 
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Pre-pre-amo

Right, I understand. I thought his unit was a phono amp (he did say phono amp), but now I understand it is a pre-preamp only. Good catch Bernard.

Guys,

THANK YOU for the clarification, although I'm not sure I fully understand :confused:

I know we called it a pre pre-amp years ago, and I have never heard the term since. I "assumed" the new term was a phono amp, but that seems to not be the case. My understanding was that some pre amps have an input called phono, but that was just an input name on most pre amps, and you are required to purchase an external phono amp, if a true phono amp is not part of the unit itself.

So we are saying that the Marcof unit I have is not a phono pre-amp?
Can I buy a cheap phono preamp for starters, such as the Music Fidelity's V-LPS, which is on sale at Music Direct for $149.00? Can I plug that unit into my auxiliary input on the Cary SLP-03?

Appreciate the help very much! :rocker:

Joe M.
 
Joe,

Way back when a lot of the phono sections in preamps, integrated amps, and receivers were designed to handle the high output of moving-magnet cartridges; they did not have sufficient gain to amplify the lower output voltages of moving-coil cartridges. If you wanted to use a moving-coil you had to buy either a transformer or a pre-preamp to provide additional gain such that it was equivalent to the output of a moving-magnet. You still needed the phono section in order to provide a correction curve corresponding to the inverse of the curve applied during the recording process; during the recording process high frequencies are boosted and lows are cut.

Today a lot of phono preamps have sufficient gain so that they can amplify the signal from a moving-coil without the use of a transformer or a pre-preamp. So, you can buy the V-LPS and plug it into your Cary, and you will not need the Marcof. There is a review of the V-LPS in the latest issue of The Absolute Sound (Issue 206, October 2010).

Note: Normally when a preamp has an input marked 'phono' there is an internal phono stage, but that is not always the case, an example being the latest ARC Reference preamp.
 
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Can I buy a cheap phono preamp for starters, such as the Music Fidelity's V-LPS, which is on sale at Music Direct for $149.00? Can I plug that unit into my auxiliary input on the Cary SLP-03?

Appreciate the help very much! :rocker:

Joe M.

I'm not sure that you will like the V-LPS...there are much better units available for similar $$. I myself like the Cambridge Audio 650.
 
I would think your player would be equipped with OM5E not OMP5E?
In that case you could relplace your cartridge with 2M red which; "The 2M Red uses an improved engine, which provides an increased output of 5.5mV"
Both cartridges are MM type so for that you dont need a MC-preamp. OM5E and 2M Red have same compliance so they are compatible with each other.
 
Joe,

Today a lot of phono preamps have sufficient gain so that they can amplify the signal from a moving-coil without the use of a transformer or a pre-preamp. So, you can buy the V-LPS and plug it into your Cary, and you will not need the Marcof. There is a review of the V-LPS in the latest issue of The Absolute Sound (Issue 206, October 2010).

Note: Normally when a preamp has an input marked 'phono' there is an internal phono stage, but that is not always the case, an example being the latest ARC Reference preamp.

I think I understand now!
I used to have all Hafler equipment and I know the pre amp had a phono section, so now I get it!

I still however do not know what Dynavector I have and if it is in good shape or not. It's been sitting idle for about 20 -25 years. I don't think I used it much though, as the CD had just come out after I replaced my old cartridge! Now I've had two "salesman types" tell me it's probably not good because the parts "break down" over time, and cantilever is probably weak, etc., etc. Of course they want me to buy a new cartridge! It looks exactly like the Karat 17D3 of today, but it has a silver body and the Dynavector name is in the side as it is today, without a cartridge name. The "Dynavector" name is on a black background just bigger than the name.

Is there a way to tell if a cartridge/stylus is "good" short of just listening to it?
I don't want to ruin my record collection! I am also wondering if the arm could go out of "synch" just sitting there. There are potentially a lot of adjustments to the SME III arm. I can't imagine why it would not maintain the proper set up over time.

I just bought a Spin Clean unit just before the price increase, along with some MoFi sleeves, a record brush and stylus brush, so I am eager and ready to get started again!


Joe M.
 
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I'm not sure that you will like the V-LPS...there are much better units available for similar $$. I myself like the Cambridge Audio 650.

Thanks. I'll check that one out too!

Joe M.
 

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