Welcome, Guest. Please Login or Register
Decware Audio Forums
09/21/17 at 18:38:11 



 
 


Pages: 1
Send Topic Print
ZP3 a humdinger !! (Read 3496 times)
Crazy Bill the Eel Killer
Seasoned Member
****


Tubes Rule !!

Posts: 136
ZP3 a humdinger !!
04/22/17 at 22:05:03
 
First, sound quality wise its beyond reproach. trounces my Sonic Frontiers Phono 1 w/ SE+ upgrades.

But the hum. Hummed from the very first. Tried lifting the grounds on the power cords to both the ZP3 and Stax SRM007tll. Nothing.
Fiddled with all the connectors and interconnects. Nothing
Hum increases and changes tone when using the ground wire from the table ( either at the ZP3, Stax, or both ). Less hum when floating.
Hum increases and changes tone when my hand gets close to any of the three signal tubes, or touches the tubes.
FWIW, the SF Phono 1 is dead quiet with the same PC and interconnects. Moving the ZP3 around does nothing.

That leaves me to the tubes. I don't have a spare set, and don't want to buy another just to see if the ones I have are bad.

Anybody, given these symptons, have any thoughts.

Thanks,                      Crazy Bill
Back to top
 
 
  IP Logged
hdrider
Seasoned Member
****


On the path with
Decware.

Posts: 406
Re: ZP3 a humdinger !!
Reply #1 - 04/22/17 at 23:37:49
 
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.
Back to top
 
 

Rachael, ZP3, ZMC 1, SE84CS, Oppo BDP-93, Sota Star TT w/ FR-64, Shinnon Red Moving coil, Omega 7XRS Mk 2 walnut, DeepOmega 8 sub, Morrow Audio PH3 and MA3 IC's, Stax Lambda Signature Pro & SRM-T1 tube amp, Gamma Electrostatic phones.
  IP Logged
Archie
Seasoned Member
****




Posts: 645
Re: ZP3 a humdinger !!
Reply #2 - 04/23/17 at 01:20:49
 
I've always had some hum with my ZP3.  I've found some tubes to be microphonic and your body has its own electric field so I can see where touching tubes might have an effect.  I never had luck reducing hum through tube choice, proximity or interconnects.  The hum or "dead quiet" each of us has reported from time to time is all relative.  You're going to have to decide if the hum is an issue.  Mine is not -- although it took me awhile to convince myself of that.  When I put a SUT in the chain with an MC cart my hum decreased but this was due to sending a higher input voltage into the ZP3 and running at lower gain through my amps.  I don't think Steve's noise spec is especially good relative to other phono stages but I think there is a trade off involved with musicality, if I've understood his White Papers on the subject.

Make sure you try it with obvious RF interference devices turned off, especially any routers.  Lastly, my hum is very different and vastly quieter from the ground hum I get when I disconnect the TT ground wire from my ZP3.
Back to top
 
« Last Edit: 04/23/17 at 01:21:23 by Archie »  
  IP Logged
Steve Deckert
Administrator
*****


If the 1st watt
sucks why continue?

Posts: 3044
Re: ZP3 a humdinger !!
Reply #3 - 04/23/17 at 01:36:09
 
How much hum do you have when you disconnect the tonearm (or sut) cables from the ZP3?

What cartridge do you run?

Back to top
 
 
WWW   IP Logged
Archie
Seasoned Member
****




Posts: 645
Re: ZP3 a humdinger !!
Reply #4 - 04/23/17 at 18:41:24
 
Quote:
How much hum do you have when you disconnect the tonearm (or sut) cables from the ZP3?

What cartridge do you run?


I'm not sure if this is directed at me or Crazy Bill but without the TT or SUT connected everything is quiet -- just what I call "tube rush," sort of white noise.  But with a dummy resistor load instead of the TT I get the same hum.  I've tried a different TT (old PL10 with a Realistic cart and an Ortofon Concord cart) and different carts on my modified Technics 1200MK2.  For listening, not testing, I've used 3 different Ortofon carts, the MM Concord, MC Kontrapunkt b and MC Cadenza Blue.

I have to turn up the gain to hear it at any appreciable distance.  My CSP3 front knobs are at 9, the back knobs are at 8 and the master is at 2 o'clock (12 being half way).  With this I have to turn my ZMA past 2 o'clock (12 being half way) to start hearing it several feet from my HR1s.  It's not quiet like my digital channel but I can't say that I "hear" it.  That said, if it could go away I'd be happier.

It Steve wasn't asking me then NEVER MIND.   Wink

EDIT:  The original tonearm was rewired with Cardas wire that terminates at RCA jacks.  I'm currently using the Decware DSG interconnects between the TT, SUT and ZP3 and Decware DSR interconnects from the ZP3 and everywhere else.
Back to top
 
« Last Edit: 04/23/17 at 19:10:51 by Archie »  
  IP Logged
hdrider
Seasoned Member
****


On the path with
Decware.

Posts: 406
Re: ZP3 a humdinger !!
Reply #5 - 04/23/17 at 19:16:49
 
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.
Back to top
 
 

Rachael, ZP3, ZMC 1, SE84CS, Oppo BDP-93, Sota Star TT w/ FR-64, Shinnon Red Moving coil, Omega 7XRS Mk 2 walnut, DeepOmega 8 sub, Morrow Audio PH3 and MA3 IC's, Stax Lambda Signature Pro & SRM-T1 tube amp, Gamma Electrostatic phones.
  IP Logged
Archie
Seasoned Member
****




Posts: 645
Re: ZP3 a humdinger !!
Reply #6 - 04/23/17 at 20:02:58
 
When I remove my headshell/cart the hum drops 75% or more, almost to the point of when I disconnect from the ZP3.  Which makes sense since the load is through the cart -- right?
Back to top
 
 
  IP Logged
Steve Deckert
Administrator
*****


If the 1st watt
sucks why continue?

Posts: 3044
Re: ZP3 a humdinger !!
Reply #7 - 04/25/17 at 02:03:50
 
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
Back to top
 
 
WWW   IP Logged
hdrider
Seasoned Member
****


On the path with
Decware.

Posts: 406
Re: ZP3 a humdinger !!
Reply #8 - 04/25/17 at 14:01:19
 
Thank you Steve, I can see from the check list I have about three items to sort out to reduce any noise in my phono system. I love this forum and Decware!! Happy listening, Chris.
Back to top
 
 

Rachael, ZP3, ZMC 1, SE84CS, Oppo BDP-93, Sota Star TT w/ FR-64, Shinnon Red Moving coil, Omega 7XRS Mk 2 walnut, DeepOmega 8 sub, Morrow Audio PH3 and MA3 IC's, Stax Lambda Signature Pro & SRM-T1 tube amp, Gamma Electrostatic phones.
  IP Logged
Archie
Seasoned Member
****




Posts: 645
Re: ZP3 a humdinger !!
Reply #9 - 04/25/17 at 16:59:40
 
Quote:
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.


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.   Smiley
Back to top
 
« Last Edit: 04/25/17 at 17:01:03 by Archie »  
  IP Logged
Crazy Bill the Eel Killer
Seasoned Member
****


Tubes Rule !!

Posts: 136
Re: ZP3 a humdinger !!
Reply #10 - 04/27/17 at 01:38:38
 
Hello all,
Thanks for your replies.

Steve:

MM cartridge. An Audio Technica AT150MLX. Plenty of gain. Will work on LOMC later on with step-up when I finally get my Beyerdynamic Mic step step up transfos in an appropriate enclosure. But that's to come.

Disconnected the phono cable from the turntable to the ZP3 and the hum dropped significantly to an acceptable level.

Any thoughts. Same hookup ( phono cables in the loop ) with the SF was quiet.

Crazy Bil
Back to top
 
 
  IP Logged
Syd
Seasoned Member
****




Posts: 1371
Re: ZP3 a humdinger !!
Reply #11 - 04/30/17 at 12:12:55
 
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.......
Back to top
 
« Last Edit: 04/30/17 at 12:15:11 by Syd »  

Decware: Rachaels x 2 bridged, C. SP2+, ZP3, ZMC1, DSC i/c`s, DHC-1 pw/cbl`s Michell Orbe + SME V + M.Benz LP s , Nakamichi LX5, Lowther acoustas DX2`s, WE 16g sp/cbl`s, Isotek mains sub
  IP Logged
metropolis7
Senior Member
***




Posts: 59
Re: ZP3 a humdinger !!
Reply #12 - 05/02/17 at 02:09:07
 

I'll share my experience:
I was chasing hum and anemic sound for quite a while. This was with a Shelter 501/SUT/ZP3 with Decware interconnects in the mix. After a lot of trial-and-error, moving this, moving that, switching out the unshielded interconnects, I decided to go with the "K.I.S.S." philosophy. Ditched the LOMC and used a strong .7mv output Rega Exact, and that was the magic cure. It was as if I had never really heard the potential of my Decware gear (FRX-2 drivers especially) until I did this.
Back to top
 
 
  IP Logged
doukhobar
Senior Member
***




Posts: 77
Re: ZP3 a humdinger !!
Reply #13 - 06/15/17 at 02:58:12
 
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?
Back to top
 
 
  IP Logged
Martindfletcher
Verified Member
**




Posts: 34
Re: ZP3 a humdinger !!
Reply #14 - 06/15/17 at 04:14:47
 
I have a denon dl103r which is .25 mv, if I did the math right the zmc1 should work.  My zmc1 just past QC so I will find out in a week or so.

Honestly the Impedance affects it as well.  Here is link to try and figure it out.

http://www.theanalogdept.com/sut.htm
Back to top
 
 
  IP Logged
doukhobar
Senior Member
***




Posts: 77
Re: ZP3 a humdinger !!
Reply #15 - 06/21/17 at 16:42:45
 
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.
Back to top
 
 
  IP Logged
Martindfletcher
Verified Member
**




Posts: 34
Re: ZP3 a humdinger !!
Reply #16 - 06/21/17 at 19:14:55
 
My project dual tube phone stage has a dial, and I set it to 100.  that is right where it does not get any louder.  Still waiting on the ZP3, it is in shipping now, hopefully it ships soon.  my  stage  also has a gain of 60db.   I should have added that prior as well.
Back to top
 
« Last Edit: 06/21/17 at 19:23:49 by Martindfletcher »  
  IP Logged
Syd
Seasoned Member
****




Posts: 1371
Re: ZP3 a humdinger !!
Reply #17 - 06/21/17 at 19:52:35
 
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   Smiley
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.
Back to top
 
 

Decware: Rachaels x 2 bridged, C. SP2+, ZP3, ZMC1, DSC i/c`s, DHC-1 pw/cbl`s Michell Orbe + SME V + M.Benz LP s , Nakamichi LX5, Lowther acoustas DX2`s, WE 16g sp/cbl`s, Isotek mains sub
  IP Logged
Archie
Seasoned Member
****




Posts: 645
Re: ZP3 a humdinger !!
Reply #18 - 06/22/17 at 00:30:41
 
Quote:


I skimmed that link and it made my head hurt!   Tongue

I use Steve's ZMC1 with a ZP3.  I just follow the directions to set the ZMC1 knob at a level where it doesn't get louder.  (It isn't always easy to tell what point this is.)  I'm using LOMC carts with different load impedances. One is 50 to 200 ohms (output impedance is 5 ohms) and the other hss a load impedance of 10 ohms (output impedance is 5 ohms).  The first has the ZMC1 dial at about 12 o'clock and the second at about 2 o'clock.  For some reason I thought it'd be a lower setting for the lower load impedance but I don't understand what any of this means anyway.

Is Steve's ZMC compensating for the different impedances to avoid the "tuning" of SUT to a given cartridge that that link seems to be saying is necessary?
Back to top
 
« Last Edit: 06/22/17 at 00:34:25 by Archie »  
  IP Logged
Martindfletcher
Verified Member
**




Posts: 34
Re: ZP3 a humdinger !!
Reply #19 - 06/22/17 at 13:54:49
 
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.  


Back to top
 
 
  IP Logged
doukhobar
Senior Member
***




Posts: 77
Re: ZP3 a humdinger !!
Reply #20 - 06/22/17 at 14:36:06
 
Yes, that is exactly right.

For a cartridge like the Hana SL which produces 0.5mV and has 30 ohm internal impedance, what is the best SUT for the ZP3? The question I've been trying to figure out is what impedance should I load the cartridge with?
The manufacturer recommends 400 Ohms (400+?). A user on vinyl engine stated he started with 1000 Ohms and enjoys that. He tested 400 Ohms but did not hear a significant difference (in his system).

Using the equation to calculate the output voltage as a function of the load resistor (Vout / Vcart) = (R(load_effective) / (R(Load_effective) + (Rcart))) to calculate the output voltage of the each SUT using the 0.5mV HAna SL output, I get:

1:10 -> 4.7 mV @ 470 ohm
1:15 -> 6.5 mV @ 209 ohm
1:20 -> 7.966 mV @ 118 ohm
1:30 -> 9.53 mV @ 52 ohm
1:40 -> 9.89 mV @ 29 ohm

I think from here I can quickly eliminate that 1:10 and 1:40 ratio SUT's.
One thing I am not totally sure on is what does providing too little load on the cartridge do to the sound?
From my reading, it seems that you want the signal into the load having at least 10 times greater impedance than the source impedance (i.e. 30 ohms) to avoid signal loss. When the source and load impedances are equal, the signal loss is 6 dB. When the source impedance is 9x greater than the load impedance the signal loss is 20dB!
Therefore, the 30 ohm cartridge will have minimal signal loss with ~300 ohm provided by the SUT.

So that is curious that a reviewed enjoyed a 165 ohm load. His stage must have alot of gain. Being that the ZP3 has only 42dB of gain, and 10*(30ohm) gives 300 ohms, that would suggest something between 10:15 and 1:10 would minimize the amount of dB loss. However, it would also lower the voltage going in.

Now, my actual experience: I found using 1:10 SUT on the ZP3 with my 30 ohm 0.5mV cart produced anemic results. The sound was very recessed. This could perhaps have been due to a wek 12AX7 tube, which I did not switch out to try with a stronger one. Steve tested my tubes and said one of my 12AX7 was a little weak. Metropolis who used a Shelter 501, which has 0.4 (or 0.5mV) and 10 ohms using a 1:15 SUT had similar results with recessed sound.

Simply from this, I am thinking the 1:20 SUT may be ideal. What are people's thoughts on a 1:30 SUT? Is going below 100 ohm loading madness?
Back to top
 
« Last Edit: 06/22/17 at 16:24:19 by doukhobar »  
  IP Logged
Archie
Seasoned Member
****




Posts: 645
Re: ZP3 a humdinger !!
Reply #21 - 06/22/17 at 16:05:12
 
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.  
Back to top
 
 
  IP Logged
doukhobar
Senior Member
***




Posts: 77
Re: ZP3 a humdinger !!
Reply #22 - 06/22/17 at 16:26:06
 
Archie - do you know how to calculate the volts out of the ZP3 based on the mV input into the ZP3?

FYI I made a typo in my above post (now corrected) where the outputs of the SUT's listed are in mV (not V). E.g. the 1:10 SUT outputs 4.7mV into the ZP3. How did you arrive at a 0.5V outpt for the ZP3 into the amps/preamps?
Back to top
 
« Last Edit: 06/22/17 at 16:26:58 by doukhobar »  
  IP Logged
Archie
Seasoned Member
****




Posts: 645
Re: ZP3 a humdinger !!
Reply #23 - 06/22/17 at 16:37:28
 
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)
Back to top
 
 
  IP Logged
doukhobar
Senior Member
***




Posts: 77
Re: ZP3 a humdinger !!
Reply #24 - 06/22/17 at 17:05:44
 
Hi Archie and anyone else who is interested in SUT's and ZP3 matching,

I actually did speak to Steve about this and he says he does have a 1:32 SUT available, but it is not on the website yet. However, he likes the sound of the Sowter transformers in the ZMC1 better. I think the transformers he uses in this 1:32 SUT are perhaps Lunhal or another similar brand, I forgot which brand he mentioned but I remember knowing it was a name brand I recognized.

Anyway, I discovered something new about my demoing of the ZP3 and Hana SL 0.5mV cart at my dealer's home and why it was not working. When we tried the ZP3 in his rig, apparently we weren't even using an actual SUT!!! He was using a vintage Klyne SK-1 device which actually is a solid state pre-pre-amp. That would explain the horrid results, as we were setting it to 30 ohms. What a disaster! Here is why (from a very smart friend) during our discussion of the calculations:

The Klyne is not transformer-based -- it is a very good solid state MC pre-preamp, it's NOT an SUT.  The selection of 30 ohms -- as you point out, resulted in significant loss of signal -- clearly too much loading for the Hana.  Would not be (at all) representative of a 1:10 Step Up Transformer with 470 ohm loading. This explains what you heard.

You correctly noted that when the cartridge source impedance (Hana @ 30 ohms) and load impedance (Klyne head amp @ 30 ohms) are the same ("matched'), you lose 6 dB in signal -- essentially converting a low output -- 0.4 mV -- into a very low output -- 0.2 mV.  Not recommended.  Well explained here --  http://www.rothwellaudioproducts.co.uk/html/mc_step-up_transformers_explai.html
Some very well-respected folks in analogue -- Keith Herron, Stan Klyne, Ralph Karsten (Atma-sphere), and Jonathan Carr (Lyra), actually recommend 47 kOhm loading, even for MC cartridges, but this is really dependent on the phono preamp and how it handles ultrasonic frequencies.


So, Steve's gear is vindicated!!! Of course I never doubted it  ::) Chalk this up to human error. I was a little suprised my dealer did not have a basic grasp of the arithmetic involved.
Back to top
 
« Last Edit: 06/22/17 at 17:06:52 by doukhobar »  
  IP Logged
Martindfletcher
Verified Member
**




Posts: 34
Re: ZP3 a humdinger !!
Reply #25 - 06/22/17 at 22:39:27
 
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.
Back to top
 
« Last Edit: 06/23/17 at 05:06:55 by Martindfletcher »  
  IP Logged
Archie
Seasoned Member
****




Posts: 645
Re: ZP3 a humdinger !!
Reply #26 - 06/23/17 at 01:42:26
 
Well, I still don't necessarily understand the engineering but I am very happy with my ZMC1 -- especially since Steve doesn't like the 1:32 as much.  I can live with turning up my CSP3 a bit.

BTW, Ortofon has what they call their "Treasure" series which are rebuilt carts that are no longer in production.  The cost is the same as sending in one for a rebuild.  They replace the stylus, cantilever and motor.  It's basically a new cart.  I couldn't resist and bought a Jubilee, which is the same as a Cadenza Black but with silver windings (as far a specs go anyway).  Cadenza Blacks sell for upwards of $3K while I got the Jubilee for a third of that.  The Jubilee is a wonderful cartridge and it will be hard to use up the life of my Kontrapunkt b and my still new Cadenza Blue (both also silver wound) with the Jubilee on hand.  

Not hard to like having 3 fine cartridges to choose from.   Cheesy
Back to top
 
 
  IP Logged
Syd
Seasoned Member
****




Posts: 1371
Re: ZP3 a humdinger !!
Reply #27 - 06/28/17 at 11:11:17
 
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
Back to top
 
 

Decware: Rachaels x 2 bridged, C. SP2+, ZP3, ZMC1, DSC i/c`s, DHC-1 pw/cbl`s Michell Orbe + SME V + M.Benz LP s , Nakamichi LX5, Lowther acoustas DX2`s, WE 16g sp/cbl`s, Isotek mains sub
  IP Logged
Crazy Bill the Eel Killer
Seasoned Member
****


Tubes Rule !!

Posts: 136
Re: ZP3 a humdinger !!
Reply #28 - 08/08/17 at 13:30:05
 
Back to the beginning.
Decided to pull out a sheet of mu-metal and play around.

To make a long story short, the mu-metal placed between the PT and the phono input jacks significantly reduced the hum to an acceptable level, even through my Stax rig. I'm happy.

Phono cable shielding not the culprit. It's a Grover Huffman, and Grover as I understand it ) uses his version of the Switchcraft plugs, which don't have a break in the shielding provided by the connector.

Got a new tonearm coming in about 6 weeks ( Riggle Woody ), that's got a continuous wire loom from the cartridge clips to Switchcraft RCA plugs. Pete builds the cable from scratch and it is extensively shielded, so we'll see if there's any difference.

Lastly, picked up a SE84CS from Parts Connexion. Hopefully it's up to snuff and I can use it immediately. It's been a long time since I listened through speakers ( my old SE84CSEX has been in pieces in the garage for over five years ). Of course any noise will be even less intrusive through speakers than through the cans.

Getting there.

FWIW, the ZP3 is ridiculously good.

Cheers,                       Crazy Bill
Back to top
 
 
  IP Logged
Archie
Seasoned Member
****




Posts: 645
Re: ZP3 a humdinger !!
Reply #29 - 08/19/17 at 18:56:17
 
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.)
Back to top
 
« Last Edit: 08/19/17 at 18:58:05 by Archie »  
  IP Logged
Lon
Seasoned Member
****


"Love without
guts is
worthless!"
Philip K. D*ck

Posts: 12614
Re: ZP3 a humdinger !!
Reply #30 - 08/19/17 at 19:03:12
 
That's good news! I haven't had bad hum with my ZP3 and I'm using Amperex tubes. But the very very quietest 12AX7s that I've tried were the new reissue Tung-Sol. I didn't prefer these overall (in fact I forwarded them on to another forumite) but they were DEAD quiet.
Back to top
 
 

Decware:HR-1,ZP3,ZTPRE,Torii MkIII,ZBIT,Taboo MkIV;PS Audio:DMP+DS,P10,PowerBases,AC-12 pcs,Mapleshade:Dbl Helix+,V2+V3;CambridgeAudio CXU;Rega RP3,TTPSU,wh belt,all Groovetracer upgrades,Exact2;VooDoo Cremona +Amati,Iso-Pods;MD90-T SE tuner,Oppo PM-1,Audeze LCD-2
  IP Logged
Archie
Seasoned Member
****




Posts: 645
Re: ZP3 a humdinger !!
Reply #31 - 08/19/17 at 19:47:25
 
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.
Back to top
 
« Last Edit: 08/19/17 at 19:48:56 by Archie »  
  IP Logged
Martindfletcher
Verified Member
**




Posts: 34
Re: ZP3 a humdinger !!
Reply #32 - 08/19/17 at 20:13:33
 
For me getting the zmc far away from the tone arm helped as well as moving the amps and zp3 further from the tone arm.
Back to top
 
 
  IP Logged
Lon
Seasoned Member
****


"Love without
guts is
worthless!"
Philip K. D*ck

Posts: 12614
Re: ZP3 a humdinger !!
Reply #33 - 08/19/17 at 20:28:23
 
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.")
Back to top
 
 

Decware:HR-1,ZP3,ZTPRE,Torii MkIII,ZBIT,Taboo MkIV;PS Audio:DMP+DS,P10,PowerBases,AC-12 pcs,Mapleshade:Dbl Helix+,V2+V3;CambridgeAudio CXU;Rega RP3,TTPSU,wh belt,all Groovetracer upgrades,Exact2;VooDoo Cremona +Amati,Iso-Pods;MD90-T SE tuner,Oppo PM-1,Audeze LCD-2
  IP Logged
Lon
Seasoned Member
****


"Love without
guts is
worthless!"
Philip K. D*ck

Posts: 12614
Re: ZP3 a humdinger !!
Reply #34 - 08/19/17 at 20:52:44
 
The vinyl loving Mark58 is probably one of the ones here who has rolled more tubes in the ZP3 than almost anyone. . . hopefully he'll visit the board and chime in. . . he may have a tube recommendation.

I just put a 6085 from Amperex in my Taboo that blows me away and is dead quiet. . . . It may work really well in the ZP3. I don't have the ZP3 in the system to try it out right now as the Taboo is in it's rack space. . . .
Back to top
 
 

Decware:HR-1,ZP3,ZTPRE,Torii MkIII,ZBIT,Taboo MkIV;PS Audio:DMP+DS,P10,PowerBases,AC-12 pcs,Mapleshade:Dbl Helix+,V2+V3;CambridgeAudio CXU;Rega RP3,TTPSU,wh belt,all Groovetracer upgrades,Exact2;VooDoo Cremona +Amati,Iso-Pods;MD90-T SE tuner,Oppo PM-1,Audeze LCD-2
  IP Logged
Archie
Seasoned Member
****




Posts: 645
Re: ZP3 a humdinger !!
Reply #35 - 08/19/17 at 21:54:15
 
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!   Tongue
Back to top
 
 
  IP Logged
Lon
Seasoned Member
****


"Love without
guts is
worthless!"
Philip K. D*ck

Posts: 12614
Re: ZP3 a humdinger !!
Reply #36 - 08/19/17 at 22:06:14
 
Amperex to my knowledge has not made tubes for decades. Those that I bought were from Ebay, I bought a three pairs of tubes, Amperex and Sylvania and RCA, the Amperex stuck.
Back to top
 
 

Decware:HR-1,ZP3,ZTPRE,Torii MkIII,ZBIT,Taboo MkIV;PS Audio:DMP+DS,P10,PowerBases,AC-12 pcs,Mapleshade:Dbl Helix+,V2+V3;CambridgeAudio CXU;Rega RP3,TTPSU,wh belt,all Groovetracer upgrades,Exact2;VooDoo Cremona +Amati,Iso-Pods;MD90-T SE tuner,Oppo PM-1,Audeze LCD-2
  IP Logged
Archie
Seasoned Member
****




Posts: 645
Re: ZP3 a humdinger !!
Reply #37 - 08/19/17 at 22:24:22
 
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.
Back to top
 
 
  IP Logged
Crazy Bill the Eel Killer
Seasoned Member
****


Tubes Rule !!

Posts: 136
Re: ZP3 a humdinger !!
Reply #38 - 09/05/17 at 02:44:15
 
Hello all,

Back to the beginning and the hum.

My post on tube swapping with the ZP3 in another thread.
"Got some NOS NIB tubes as follows for the ZP3.

RCA mid 60's 12AX7A for the first two positions.

Brimar, mid 60's NOS NIB cryoed CV4003 for the 12AU7 position.

Holy Shit Batman !     What else can I say ?

These tubes, in the ZP3, I'm done and happy.

this is music, pure and simple.

Try these tubes, I can't imagine anyone being disappointed.

Cheers,                       Crazy Bill "

Well, the noise level also dropped significantly. As noted earlier in this thread, hum would greatly increase when I put my hand on or near the first 12ax7 tube. With this tube compliment, if I put my hand on the tube near the cathode ( bottom ), a very slight increase was noted. VERY SLIGHT. Way less than even getting close with the stock compliment.

Through my AKG and Sennheiser cans the noise level is low enough that I'm happy.

BTW, the Zen makes an incredible headphone amp.

Cheers, Crazy Bill
Back to top
 
« Last Edit: 09/05/17 at 03:01:24 by Crazy Bill the Eel Killer »  
  IP Logged
Pages: 1
Send Topic Print