Bill- The hum I got off our ZP3 when I set the system up originally was a proximity issue (ZP3 too close to Rachael) and once I moved things around it's pretty quiet. Not DEAD silent, but it never invades the music. The fact that it's louder when your hand is near the tubes is kinda odd though. Guessing the tubes, call Decware on Monday and see what they think. You will love it more when this is sorted out. Happy listening, Chris.

How much hum do you have when you disconnect the tonearm (or sut) cables from the ZP3?

What cartridge do you run?

With the cartridge disconnected from the SUT>ZP3>Rachael the hum is the same as with the cart connected. Disconnect the SUT and ZP3>Rachael are dead quite. I need to run the cart direct in to the ZP3 just for ducks to see how much hum there is. I know I need the SUT for the LOMC but just to check.

When running an SUT with the ZP3 it is imperative that the ground wire from the tonearm be connected to the ground post on the SUT and then an additional wire must be used to connect the ground lug of the SUT to the ground lug of the ZP3.

Also shielded cables must be used between the tonearm and the SUT, and between the SUT and the ZP3.  

Eichmann bullets or any other plastic RCA connectors can not be used irregardless of whether or not the cable is shielded.

It is important to use MM cartridges that are 4mV or higher with the ZP3 so that no additional gain from a preamp is required.

When using an SUT, it is important that you have at least a 20:1 ratio so that you can again achieve a strong output level from the ZP3 without needing a preamp.

Using a preamp or gain stage with lower output cartridges or SUT's works just fine so long as your vinyl rig is quiet. Any noise that is there will be increased exactly the same amount as the music volume so you can see where this becomes problematic with certain setups.

Also make sure you don't have any WIFI routers, wireless devices, digital light dimmers or florescent or LED light bulbs anywhere near your vinyl rig.

We have never had to lift the earth ground at the power cord to achieve hum free performance with the ZP3 so if that improves things it's a sign something is wrong somewhere else in the system.

The front tube on the ZP3 (12AX7) is the most sensitive to noise and or picking up hum.  Some tubes are quieter than others.  make sure you use the factory tube compliment until you solve your hum issues... then roll tubes if you want. Be aware that not all 12AX7 tubes are silent as advertised, and N.O.S. tubes are often noisy and or microphonic because lets face it, what is left in the N.O.S. stockpiles are the scraps of yesteryear, not to mention many have been beaten around during transport many times over the past 60 years.

Also, when determining an acceptable amount of hum on any vinyl system be it solid state or tubes, you simply turn the volume up to your normal listening level and then cue up the cartridge of the record and whatever noise you hear is what you got. What you don't do, it turn the volume on your preamp or amp all the way up when the cartridge is cued to induce hum.

Hope this helps. Also there are some SUT's that are wired funny with respect to ground. There are some tonearms where the ground wires are reversed between channels unknowingly and work fine with SUT or phono stage that have common ground, and have big issues with SUT's or phono stages that don't. There are enough subtly different ways to ground a vinyl rig that it inevitably results in a small number of systems having issues. Even an intermittent ground in one of the 4 IC cables can when combined with the right variables work fine in one setup and cause serious headaches in another.


Steve

Quote:


Well, that said, I tried my ZMC1 with all combinations of grounding when I first put it between my TT and ZP3 and found that having no ground to the ZMC1 was the best.  I got slightly less hum by just running my TT ground to the ZP3 as I did before the SUT was in use.  I've followed everything else Steve said and as I mentioned, hum is acceptably low (though still present) in my system.  

With respect to Steve's advice about using a preamp, while waiting for my ZMC1 last year, I ran my .5mV MC cart directly through my ZP3, CSP3 and into my ZMA.  I listened at full gain and despite the ridiculously amplified noise/hum, still had enjoyable listening.  

Also shielded cables must be used between the tonearm and the SUT, and between the SUT and the ZP3.
Thats where I could improve. I`m so taken by the fidelety of the Decware silver ref i/c`s that I use them throughout, including ZMC 1 SUT to ZP3 phono. Tbh I dont know if these are shielded and have taken a lot of time positioning these two amps to minimalise any hum. Driving 89db panels meant the CSP2+ was at 75%. Any slight hum would be heard in quiet passages. Now driving 97db Lowthers the CSP2+ is at 30% and quiet.
Not the full story though. Ditching the BB 6dj8`s and using the Russian and now Shuguang 6922 equivs has helped to the extent that I cant introduce a BB back into the CSP2+ without it complaining loudly. Then the 807 power tubes into the Rachaels were found to be quieter than other NOS EL34`s and Foton coin base tubes.
I havent rolled a tube for 6 months except for 2, 12ax7`s in the ZP3 from my small stock a couple of weeks ago to give me more bass presence. A Mullard at the front and a trusty Sylvania triple mica. A Philips Miniwat 12au7. I could go quieter no doubt but I feel I have thouroughbred not to be tampered with untill.......

That everyone for answering all these questions about the ZP3 and cartridge and SUT combinations.

FYI, the Rega Exact cartridge puts out almost 7mV of signal (not 0.7 mv for future reference), so that is a lot of signal going into the ZP3!

I would like to hear from more folks using LOMC cartridges. I just puchased a Hana SL which outputs 0.5 mV. We tried it with a 1:10 SUT into the ZP3 and the sound was 'anemic' as Metropolis described above. I am hoping a 1:20 SUT will solve my problem.

Anyone experience something similar? Anyone try a 1:30 SUT with the ZP3?

Thanks! That is a great link. Do you know how much impedance to load your cartridge?

That is exactly what I am trying to figure out now. I've seen reports of people loading my cart from 1000 ohm down to 175 ohm, so it's obviously a matter of taste. The manufacturer recommends 400+ ohms. A professional reviewer after testing 100, 400, 200 and 165 ohms settles on the 165 ohms. I think they have a variable loading somewhere, maybe built into their phono stage.

For my cart, a 1:10 takes the 0.5mV and produces approximately 5mV. The ZP3 has a typical load impedance of 47kOhm.

According to the calculations in the link, using a 1:10 SUT on the ZP3 loads the cart 47,000/10^2= 470 ohms. The link above confirms this value for standard MM phono stages like the ZP3.

However, what about using the 1:20 SUT? What would the load presented to the cartridge be in this case?  In this case the math is 47,000/20^2 = 117.5 ohms.

Bob at Bob's Devices who makes a switchable SUT from 1:10 to 1:20 confirms the 1:20 impedance loading value:
"Into a standard 47k phono preamp, the effective input impedance of the low gain (1:20 ratio) is  118 ohms.  At 1:40, the effective input impedance is 29 ohms".

Anyone have the Hana SL cartridge and like to share this experiences? I am checking on vinyl engine website too.

Good to see you grappling with the impedance/resistance calculations. I just use the multiplication factor to aim .4 or 5 mv`s at the ZP3.
It just got too much trying to take to many factors into consideration.
One site says I should use X10, another X20. I went for the X20.
The ZMC 1 has a dial which I take to be the imp/res thingy. Yes I got that burned out getting my head round all the things to be taken into consideration that imp/res has become fictional  
My bottom line now is.....the ZP3 has standard resistance. The ZMC1 knows this and accomodates all normal carts.
The dial on the ZMC1 must be connected to something because when you turn it max one way it creates distortion. I have it nearly max the other way, with plenty of wiggle room.

Perhaps a real electrical engineer can chime in, but as understand it there are two main variables to compensate for when selecting an SUT  1) output voltage 2) cartridge internal impedance.  The lower the output voltage the more turns you need 1:20 or 30 vs 1:10 dependent on the  impedance.

Without the impedance dial like the zmc  it is more critical to get it exact or use resistors to dial it in.  

doukhobar,

If I understand your example, the 1:10 gives the best "numbers" since the manufacture recommends 400 ohms.  But forgetting that, it would give only 0.5 volts out of the ZP3 which, from my experience, needs a CSP3 to give good results from my amp.  A 1:20 still only gives 1 volt out of the ZP3 -- better but still not ideal with Steve's amps.

If the ZMC1 avoids the numbers game, why not try one of those?  It would be nice if Steve made a 1:30 SUT too.

I just got an Ortofon Jubilee, which is a wonderful cart but only puts out 0.34mV.  There is a noticeable gain reduction when compared to my 0.47mV cart.  The practical difference is that I have to turn everything up a bit which increases noise slightly -- not a problem in practice for my system though.

I'm sorry if my comments don't add anything to this discussion given how confused I am about all of this.  But I do own and use these components.  

Try this link:   Quote:


I use the formula given.  I've corresponded with Steve some on this topic and he never contradicted the formula but I find it odd that phono stages put out such low voltages.   My first phono stage was an NAD (PP2?) with 35 db gain.  I actually think that stage seemed louder than the 42 db ZP3.  I originally used a 5 mV MM cart and when I went to a 0.5 mV MC with the 1:20 ZMC1, Steve correctly predicted that I would get less noise since I would be getting twice the output from my ZP3, which was the case.  (1 V with the MC vs. 0.5 V with the MM)

I was wondering why it sounded so bad, from the numbers it should have worked at least half way decent.  I would think my DL-103R would work with 1:10 or 1:20.

Here is a handy referall chart I also used. Did it make it all clear ? Yes and no.

http://www.sowter.co.uk/phono-cartridge-transformers.php

I may have had a HUM reducing breakthrough with my ZP3.  I've been running the original 12AU7 yellow labeled long plate Raytheon tube that Steve shipped with the unit.  Figuring it must be getting tired, I bought two red labeled Baldwins and one yellow labeled long plate Raytheon to try.  After trying the red Baldwins (no change compared with the original Raytheon)I tried the new yellow labeled today and I'd swear that the hum has been cut in half!  I haven't switched back yet to verify but I wanted to check with other ZP3 owners to see if anyone has had a similar experience and if anyone can recommend other 12AU7s that might prove to be super quite.  I've changed all the other tubes enough to think I wont get any improvement in hum by changing them.

Thanks!  (BTW, I'm not likely to try rare, expensive tubes.)

Lon,

Have you ever noticed noise changes with the 12AU7 tube?  Changing the 12AX7, in the first two spots, has never changed the level of hum for me and I've tried many over different brands and both new and old.

My challenge really came when I switched to a lower output cart and had to up the gain on the amp which naturally upped any inherent noise.

Yes, the 12AU7 is likely the one that would exhibit the most noise. I have never had a situation where the noise really bothered me. I had the most noise when I ran the ZP3 into the CSP2+ and then to the Torii, when I decided to run the ZP3 into the Torii directly I never was bothered by noise. (It was when I was using the CSP2+ in the chain that I swapped in the Tung-Sols and noticed a "quietening.")

Thanks Lon.  At least now I have an idea of what to try.  Are the Amperex new or old stock?


Martin,

My hum has always been associated with the ZP3 and has been resistant to tube swapping (up 'til now), interconnects, grounding scheme, carts or placement.  With higher output carts it's not an issue.  Before my ZMC1 arrived I even ran my MC cart straight off the ZP3 with the CSP3 and ZMA turned way up.  Talk about hum then!  

Thanks Lon.  I'm not tube savvy.  I might try a bulk lot of various makes on ebay, if cheap, and just try my luck.

Hello all,
Still going crazy. Most nights the hum is low enough, but not all nights.
Now I've got a serious buzzing sound I can hear on top of the hum. Not all the time. Driving me crazy.
Here's the weird thing about it. If I put the headphones on BEFORE I TURN ON THE ZEN AND ZP3, the buzzing sound is there with absolutely no AC applied to anything.

This turn on any light bulbs to anyone ? Really want to get this set-up quiet enough to enjoy.

Thanks for any help,                     Crazy Bill

Quote:



With respect to hum coming through your ZP3 when it is on - the order of most to least likely causes are:

GROUND

TUBES

LOCATION

CABLES

WIFI

BLUETOOTH

DIGITAL LIGHT DIMMERS

LED / FLORESCENT LIGHTS

With respect to hum or buzz coming through the headphones before the amp or ZP3 are on, EMF which is the last four items on the list.

-Steve

Okay forgive me but the buzz. . . it sounds like what my best friend describes as part of his tinnitus sounds. . . . .

First,
Thanks to all for your responses. Much appreciated.

Lon,
No tinnitus. While I do very occasionally get it, a quick descending airplane depressurizing trick fixes it almost immediately. Though it does scare the hell out of me that someday it will linger and not go away. I keep my fingers crossed.

Right now I am listening to absolutely sublime ( very low hum ) analog.

Steve,
I'm thinking that your response might be on to something. My wife is upstairs in bed already. Many times she is sitting in the chair next to my turntable playing on her IPAD. Which means she's transmitting full force on the wifi. Never made the connection before, but she's not there and it's very quiet. Going by memory ( not a good thing at my age ), the last couple of times that buzzing sound was there so was she.

Clearly, I've got some playing to do. But right now, I couldn't be happier with what I am hearing.

On another note, got a new tonearm in house for about a month now.
A Riggle Woody Universal.

All I can say is WOW !!
More to follow later.

Cheers, Crazy Bill

did we ever figure out the HANA SL cart solution?

i finally got my new Hana SL cart (replacing denon pulse 103) with ZP3 and ZMC1.  it was dead silent with the 103.  put on this Hana and i have an obnoxious hummm!  

i didn't dive into this last night... didn't have it in me.

i didn't change anything but the cart.  so i am assuming i need to configure the grounds differently.  this phono stuff can be a pita!

got it!  first try.

i removed the second grd from sota to zp3, and ran it between the zmc1 and zp3.

perfect again.  i don't understand all this grd stuff.