Does phono stage noise drive you crazy too?

If you are in the 61 db setting are you possibly loading down the cartridge at 100 ohms as a moving coil? This cartridge wants to see 47K ohms and 100 ohms will really reduce the output of the cartridge which will cause noise problems. Be sure your are loading at 47K

Thanks for your responses. There is no mismatch as to loading or capacitance. In fact, Grados are unaffected by capacitance if one believes factory guidance. I'm running around 250pf of capacitance (cabling + preamp) & 47k loading. Tonearm cabling is a brand new continuous litz loom in the Audiomods arm I recently bought. I don't want to make my noise obsession sound as if this is a really blatant problem. I'd imagine many people wouldn't notice or care. It's just that with something like my high output Garrott Optim FGS, there's a noticeably better signal to noise ratio. The volume level of any given lp's mastering is a factor too. Elvis Costello's "My Aim is True" MFSL remaster has a lower than usual volume and it's particularly noticeable playing that lp.

No, sorry. Don't have this problem. As you have experienced, when you start moving up the cartridge food chain the demand on phono stage performance goes up dramatically, not to mention every other piece in the system.

Me neither my unit is tubed and the only time I can hear any noise (hiss) is at wide open throttle. But I could never listen at anywhere near this level. So it sounds like system interaction or set-up issues.

Chuck

53db. A weighted noise it turns out

What does this mean? Are you saying that at the listening position you measure 53db A-weighted noise with an spl meter, with the volume control at a setting that you would use for listening? If so, that would definitely sound like there is a problem somewhere.

I'm wondering if the hiss could be caused by rfi pickup. Have you tried unplugging power to everything that is not necessary for phono playback, especially the video stuff? As well as turning off any dimmer switches and fluorescent lighting that may be in the area. Also, it would be interesting to know what the noise level would be with shorting plugs connected to the phono stage inputs, at the same gain and volume control settings.

Regards,
-- Al

Isn't there a high output version of that cartridge? Maybe you could exchange yours for the high output version

Hi, photon46, I'm running an AcousTech PH-1P and it isn't any more noisy than several other phono stages I've used. That's with a 0.23 mV output cartridge set at 52 dB of gain. I do wonder if you've got other problems in the signal chain, as the others mention. For one thing, I wouldn't expect such a dramatic change in sound between the 61.5 dB gain and 52 dB gain settings. Something doesn't seem right.

Running the 0.5 mV output Master at 52 dB of gain and letting your preamp take care of the rest should help to lower noise from the PH-1P (IF that's really where the problem lies) but the Master shouldn't sound "lifeless and anemic" at the 52 dB setting.

Regards,
Tom

Al, I wondered about RFI myself. I experimented with making a copper shield that grounded to the mains plug connection and used Stillpoints ERS cloth to further shield things. There was a very slight decrease in circuit noise, but nothing really noteworthy. The 53db. A weighted noise figure was provided by the factory, not what I measured from my listening seat. Man, that would be loud noise! My wife can't even hear the hiss from the listening position. Like I said, it's not very loud. I'll dig out my shorting plugs and see what happens to the noise level.

Tom, yes I was expecting to be able to use the 52db. gain setting and was most surprised to find it lacking. I'm certainly wishing I'd done my retip exchange for a 1.0mv version instead of the .5 version. Maybe I'm indulging in a bit of hyperbole to say "lifeless and anemic," but at 52db of phone gain, there is a definite lack of drive and "meat on the bones" compared to the 5.0mv Sonata I traded in on the Master 1.

It may just be Grado. try something else. I never found a phono stage that works well with their low output cartridges.

The 53db. A weighted noise figure was provided by the factory

Assuming it is based on one of the commonly used test conditions and reference levels, a 53db A-weighted s/n ratio is in a ballpark that I would expect to result in the audible hiss levels that you seem to be describing.

In addition to trying the shorting plugs, it might also be worthwhile assessing the hiss levels with the cartridge and cable connected and with loading set to 100 ohms or thereabouts, while you are not playing a record but with the volume control set to where you presently use it.

Perhaps the reason for the better noise performance that Tom reported is that the heavier loading (lower resistance value) that he was probably using in conjunction with a LOMC improved the s/n performance of the PH-1P, relative to what it would be with a 47K input impedance. That possibility would seem consistent with Lloyd's observation, as well. 47K input loading would also seem likely to increase rfi susceptibility, compared to a low value such as 100 ohms.

Also, I note that the Grado's inductance is 2mH, which is considerably higher than that of many and I believe most LOMC's, and would not come close at high frequencies to being the near-short across the phono stage's input that those LOMC's would be. The near-short would presumably reduce both self-generated noise in the front end of the phono stage and rfi susceptibility.

Just some thoughts. Regards,
-- Al

Hi, Al; I've been loading the LOMC cartridge at 200 Ohms and 300 Ohms resistance using resistors in the custom loading slots of the PH-1P. I tried 4.5K and 1.0K Ohms resistors but the presentation, while very lively, was a bit too forward (bordering on bright) for my tastes in my setup. I haven't noticed any difference in background noise between the range of 100 to 4.5K Ohms resistors I've tried but I wasn't really listening intently for any differences that might be present. I never did try the 47K Ohms setting.

Regards,
Tom

Dear Photon46: Maybe I'm wrong but you Aloia preamp has the phono option that maybe could works better with your Grado.

You posted that with 52db on phono gain the performance is anemic.
52db + at least 10db additional gain from your line stage is a lot of gain and IMHO enough for that Grado for not have that problem and certainly not for sound be anemic.
So IMHO there is a mis-match between that phono stage and the Grado or that phono stage is out of specs.

Btw, check that the Grado pin connectors are connected in the right way and makes tight connection with the tonearm four wires.

Why don't try the Aloia with phono card?.

regards and enjoy the music,
Raul.

Any noise drives me crazy !!!!

Al, I reinstalled the Grado on my arm and then set the resistive loading to 100 ohms instead of 47k. That does ameliorate some of the problem. The character of the noise is now softer, less high frequency hash in the circuit noise. I'll have to see if I can try a proper moving coil and see if the ultimate answer is going to be a different cartridge or phono stage. I really like the character of both the Grado and the Ph1-p, but they aren't an ideal match it seems.

Raul, I definitely thought about trying an internal phono card in the Aloia, but the factory won't respond to emails and there isn't a U.S. distributor anymore to my knowledge. There have been a couple that popped up on Audiogon with the phono option, but what holds me back is my doubt that an internal phono card is going to equal the ultimate potential of a high performing stand alone phono stage.

I suppose I might also mention that a low output Grado, as the factory has stated to other Audiogoners, doesn't seem to care what resistive loading it sees. It sounds basically the same running into 100 ohms as it does into 47k. I'd never bothered to test this before, but it's true as far as my ears can tell.

Sounds like you've made some good findings.

A 100 ohm load in conjunction with a 2mH cartridge, though, will result in significant rolloff of the top octave (10 to 20kHz). You can see that by plugging those numbers into the calculator in the section labelled "MC Cartridges" near the bottom of this page at the Hagerman site, which indicates a bandwidth of only 8kHz for that combination. (To a reasonable approximation, I don't think the fact that the Grado is not a MC is relevant to that calculation). My impression is that it is capacitance that the Grado's are pretty much insensitive to.

With respect to deciding whether to replace the cartridge or the phono stage, keep in mind that going to a LOMC having significantly less inductance than the 2mH may lower the noise levels even further than they are with the Grado and 100 ohms, even if the same 100 ohm load is used. 2mH at 20kHz corresponds to an inductive reactance of about 250 ohms. A LOMC having an inductance of say 50uH or less would be only a few ohms at 20kHz, and so would be equivalent to a near-short across the phono stage inputs. Although that benefit would trade off against lower signal levels for cartridges having output levels significantly below the 0.5mv of the Grado.

Regards,
-- Al

I'm using an Ayre unit which is DEAD quiet. It sounds to me as though your pre is working too hard. Try reducing the output level and turning up the volume control on your preamp instead. The less hard phono stages work, the better they are.

When I reinstalled the Grado, the first thing I did was to try it at the lower 52db. gain setting again. It did not sound "weak and anemic" anymore at that gain setting, so I surmise that I must have underestimated how long it was going to take for a brand new cartridge to break in. When I adjust the phono gain to either 52 or 61db. gain and then set system volume to a measured 79-80 db. playback level, the background circuit hiss sounds pretty much the same to me. Don't know what to think about that, confounds my expectations as well.
Thanks Al for all the advice. It would be interesting to run a frequency analyzer on this combo to see what the frequency response is. If there's a severe roll off above 8khz., my middle aged ears aren't hearing it yet.

When I adjust the phono gain to either 52 or 61db. gain and then set system volume to a measured 79-80 db. playback level, the background circuit hiss sounds pretty much the same to me. Don't know what to think about that, confounds my expectations as well.

That's not surprising. Assuming no special problems such as ground loops are present, overall noise performance will usually be pretty much determined at the front end of what comes first in the chain, because signal levels are lowest at that point, and any noise that is generated or introduced there is amplified by everything that follows. That is particularly true if the gain of what comes first is high compared to the gain of what follows, as it is in this case even at 52db.

So I would not expect noise levels to be affected in any major way by how the overall system gain is allocated among the various amplification stages in the system.

Regards,
-- Al

Give Grado a call and ask if they can bump up the output. I think they can add some coils.

I had the same problem with my Grado Statement Sonata1 using the Grado PH-1 preamp. Reading this thread was like having a deja-vu. My (short story) solution was to upgrade the op-amp in my PH-1 from the NJM4556A to 2 x OPA627's mounted on a Browndog single to dual op-amp adapter. I tried other op-amps (opa2134, opa827) and found opa627 to be superior. It was clearer, quieter and more dynamic at high output with barely any hiss. In addition, I bypassed the PH-1's output coupling caps with 0.1uf micamold pio. Now the sound is as dynamic as anything I have ever heard and I have to put my ear to the tweeter to hear any hiss. I am finally enjoying this cartridge.
I tried using Hagerman's piccolo moving coil step up amp but that didn't work out. I'm told you can't use a MC step up transformer with a MI cartridge, so I didn't bother. My tube phono stage didn't have enough gain either. Now I was starting to understand why people preferred moving coil cartridges; their low outputs can be stepped up quietly without using an active stage (which adds hiss). IMO, the statement series needs at least 60db gain with no hiss to be enjoyed, and I wasn't going to throw good money after bad searching for another phono pre. I contacted Grado about the issue and got this kind of reply: "??? what are you talking about?". Their most useful suggestion was to reposition the phono stage, which I had already done with of course no effect. Here I was using a Grado cartridge with the Grado Preamp and the hiss was annoying the urine out of me. If I hadn't accidentally blown out my PH-1 necessitating it's repair, I would have never stumbled upon a solution.
Good luck, I hope this helps.

Not really.

I thought I'd post an update. After doing a bit of further research, I thought I'd try something a little higher up the audio food chain to see if a more compatible preamp with low output Grados could be found. A couple of emails later and I had one of RCM's Sensor Prelude phonostages courtesy of Mehran at Sorasound headed my way. After living with it now for a few weeks, I can say this has been one of the best audio purchases I've ever made. It took what virtues the Acoustech PH1-p had and expanded upon them, added tonal density, and does everything with much less background noise. It's a truly excellent sounding product that balances insight and soul. Using the Grado Master at similar gain settings with the RCM and the Acoustech proved once again that while specs may be similar, numbers don't tell the entire story.

Yes, even if I can only hear it when nothing is playing.

The two types I have had to deal with in practice in recent years is EM and hiss from noisy or aging tubes.

EM inducted noise really bothers me and I have zero tolerance. I suspect it affects sound quality even at levels not easily heard in practice. Mu-metal shielding around my step up device was the solution. Hiss from noisy tubes can also bother me but not as much.

My Manley Steelhead is quiet as the grave. Love it. Not sure if you have tubes in your setup but when I first received my Manley amps one of the input tubes had been damaged during shipping and produced some noise similar to what you are describing. I swapped out the tube and POOF no more problem.

PMB