I rec'd my ZP3 last week and have it up and running along with a ZMC 1 in front of it. I am getting a low level oscillation / motor boat sound out of the left channel only. Rachael amp alone, no oscillation. When I have the ZP3 plugged into the Rachael without the ZMC or Cart it is still there. Played with gounding points for the TT, ZMC1, ZP3 and all had no impact. Changed the two 12AX7 in the front of the ZP3, no change. I am going to swap the Valve Arts 274B that came with the ZP3 with the one that came with the Rachael tonight when I get home, see if that makes any difference. Anyone have strange sound during break-in that disappeared after the first 50, 100, 200 hours or should I call the mothership and ask for help (I think it may be too soon)??? Thanks, and happy listening. Chris

JD - I have a Sota Star Sapphire turntable with a FR-64 arm, same table, cart, arm I used with my ARC SP-11 without the motorboating sound. The TT is on top of the rack and ZP3 is 24'' below that and the amp is below that. All IC are shielded and I have checked them with a volt meter and cable tester. It's faint but you can hear it on quiet passages. The Rachael is dead quiet on cd, dvd, or streaming. The thing is with just the ZP3 plugged in to the amp I still get the sound out of the left channel. It does not get louder when I add the ZMC1 and cartridge. The fun of phono!!

Let us know if and how you were able to eliminate the thumping when you do. I'm curious

thanks

JD

Hi chris, my ZP3 is a bit fussy and took a while to get it happy. Finally figured the input i/c`s  needed to be just so, as if the transformer was playing a part.  Of course the dial on the ZMC caused a racket when it was at max either right up or down, cant remember which.
Great score on the TT. Unusual vacuum system pulling the record tight on to the platter surprised me when I did a quick read up.
I know you`ll think wow when it the music starts captivating.

As a way to ascertain the purity of my sound I always turn my amps up once  warmed up without the volume of my source turned on.  This allows me to find peak volume without any type of buzz, hum or interference during listening sessions. One of the reasons I love Decware is that I don't have to turn it down too much (maybe 7-15%) to hear complete silence which for a total tube system is righteous.  Once I turn down to complete silence which depends on tube contingent( i don't mind sacrificing some microphonics if the sound is worth it aka some 7308's, and source I then turn up the source and manage weight, treble, balance etc. to find the magic zone.  
With various sources the addendum that isn't music isn't always noticeable or relevant but there none the less. The whole tree falls in the woods but no one is there to hear it philosophy. If any sound including motor boating is there when you have the volume up it is still there even if you don't hear it when volume is lower.  To me that matters but to most it doesn't. My point in posting is that you guys probably do care.  I just took the plug pin out of the zp3 that is there for grounding since my rega p6 doesn't need to be grounded and wow.  I think it's been transmitting energy into my signal to the amp therefore affecting sound.  I only realized this after switching some shielded cables (decware which for the price point are a steal) with my favorite unshielded grover huffman cables.  Guys wow what a great result.  
Sorry for being so verbose but sometimes it's what we take away versus what we add.
As Dusty Springfield sings in the back ground over and out.

JD

All resolved! The ZP3 does not like to be directly above Miss Rachael in the rack. I was pretty sure it was some kind of proximity problem. Moved it up two shelves, and there is no motor boating and all in all pretty quiet. Now I really need to rack up some hours on the ZP3. Cowboy Junkies, Dregs, Jeff Beck all sounded GREAT. I am so happy with these two products! Thank you Steve and Decware Team!!

nice

JD

My mc cartridge has either .2 or .3 output, which I run into a ZMC1 step up > ZP3> Rachael. I have the loading control on the ZMC1 at the 3:00 pm position (this control does affect the overall volume/gain) and if I turn the volume on the amp all the way up I have some low level hum. That is too loud and I would never be able to turn the music up that load due to clipping. At the levels I listen to records the unit is very quiet. I would talk to Steve if you think there is a problem with your unit. Once I got the ZP3 moved up another 9'' about the amp, I don't have the motor boating sound at all. When you think about all the gain required to get a small signal boosted to drive an amp I am amazed how quiet it is. A lot less noise than the ARC SP-11 that it replaced. Let me know how your trials progress. Happy listening, Chris.

I can echo that I have an audible hum when volume is turned up all the way on my zp3 but at listening levels my zp3 into my torii III is totally quiet.  The zp3 is EXTREMELY sensitive and there are many possible reasons for hum but most seem to be related to voltage differences between the amps, connections etc. and the emf frequencies of all equipment/sources that are being used.  It is possible to make quiet but also easy to have the opposite occur.

JD

Archie - I don't think that we could ever eliminate ALL the hum/noise in the phono stage, but that is at a level we don't listen to the music at. You have a healthy output from your cartridge, I may look into a medium output mc next time around. I think maybe a trip back to Zen central to have Steve verify that your particular unit is 100% would be worth the $. I am a happy camper based on what I have heard so far, this ZP3 SMOKES my ARC SP-11 and it is not even broken in! Tone, sound stage, frequency top and bottom are all way better. This phono and amp make my Sequerra speakers sound like better than new, though I am still thinking about a different speaker system. Keep us posted on your ZP3 and the step you decide to take. Happy listening, Chris.  

Archie- sit tight, listen often and have fun. Get those HR-1's broken in and then make a decision. HR-1….I am so drooling on my keyboard right now.

I think I waited more than six months for my latest pair of HR-1s. I wouldn't want to be without them. You'll definitely experience more depth and the soundstage should be amazingly different.

I can't tell you how many amps I had that hummed, and sometimes not even in the correct key! Nature of the beast back in the day. Finally got away from it when I went wireless on my bass guitar, also stopped the shocks on the mic. Our Rachael and ZP3 are breaking in nicely. Actually sat down after work with Gigi and listened to Loreena McKinnitt ''Mask and the Mirror'' and she mentioned all kinds of things she has heard (a lot of them related to the break-in of the amp) over the last few week. Loving it all. Happy listening, Chris.

If it ain't hummin' (too ound) and your toe is tapping...I say happy listening. One thing about phono listening is that it takes the attention to the most minor of details of gear set up/ positioning to a new level. Enjoy, Chris.

Archie - If your system hums with the ZP3 plugged into your amp but with NO TT plugged into the ZP3 and the volume at a ''normal'' listening level you may have a problem with the ZP3. That is how I solved (mostly) the hum in my ZP3 (proximity of the ZP3 to Rachael amp). Good luck and keep us posted. Chris

I think that if you have a tranny humming like that it needs to head back to Steve @ Zen central for a once over. I am listening now while my 2 1/2 year old grandson naps and it's getting better each album side. The background hum I hear without music playing and the level up almost all the way is not present a normal levels (and I am listening a little lower now while Cooper naps). I am loving this gear more and more, as each side plays.  Kitaro, Genesis, Lorenna McKinnett, David Grisman…I am floored. Happy listening, Chris.

Steve replied to my questions about hum and Hiss the following way (he, of course, offered to look over the unit under his Lifetime Warranty):


I see two issues in your email.  

A) The unit hums without anything hooked to it, meaning you hear a mechanical vibration.  This could be from one or two things.  The power transformer, or the rectifier tube.  I would change rectifier tubes and see if the amount of hum changes.  (There will always be a small amount of mechanical hum from transformers) and since you say your other Decware products are fine, it leads me to believe it's the tube.

B) Hum through the speakers.  With a phono stage (tube type) there is always some hum, the trick it to get it below the noise floor so you don't hear it.  That means that at your normal listening volume, you should hear no hum.  If you rotate the volume higher you will eventually hear hum.  If the hum is audible without the input cables from your tone arm connected to it, and the volume set to your normal listening level, then you either have a noisy tube or some other issue.

Sounds like your ZP3 is hum free (small amounts of hum are normal in a tube phonostage, but you would have to really max the volume to detect it.) and that the hum you do hear is coming from your tonearm cables, tonearem or cartridge. That too is not unusuall, but it is possible to have the three items work well enough to be undetectable, ...


Regarding the hiss I hear when the ZP3 has no input connected:

Correct, hiss is not hum.  The level of hiss is directly effected by the smaller 9 pin tubes.  The front one being the biggest player in noise and or hiss.  If you try different 12AX7 tubes in the front you'll hear the character and amount of hiss change from tube to tube, some are quieter than others.


So, I have concluded (for now) that everything is spec with my ZP3.  I changed around rectifier tubes with no noticable change in the mechanical hum.  I also have noticed that my CSP3 has a similar hum but a little quieter.  Mechanical hum is low and not a problem for me.  I don't seem to have that magic combination of TT, cart and interconnects but the audible hum isn't really an issue.  One last thing that Steve mentioned that made me laugh is that this Forum "can be like a forest fire."!  I guess the interpretation of that is up to each of us!  

HDRider and Archie - thanks for the comments.  Have been away for a few for eye surgery (successful).  Concerning the hum from my ZP3, and the cables, etc.:  the Rega tone arm was rewired with the Incognito kit, a single run of Cardas cable, from the cartridge to the RCA connectors at the phono pre.  I tried three different interconnects from the ZP3 to the ZMA (Cardas, Acoustic Zen, Decware) with minimal differences in the hum.  I thought that the tighter connections at the TT and ZP3 RCA interface using AQ 90 degree connectors solved the problem - but not quite.  I have discovered that pushing laterally on the right channel TT/ZP3 interconnect produces a little "pop" in the right speaker and the hum disappears temporarily.  If I touch the right channel TT cable the hum may return, louder or softer.  Another push makes it go away.  I suspect something is going on with the right input on the ZP3.  Any thoughts?....

RickVee:  I've found that poking around my cables and tubes can cause popping and clicking that I originally thought was due to some kind of microphonics.  I was told by Keven at KAB, however, that the clicks are due to some kind of ?dielectric? discharge and that Cardas wiring in the tonearm can even cause this due to tonearm motion.  Don't quote me on the physics!  I also found that one of my interconnects seems to have a poor connection at the connector (causes noises and dropout when moved around) so I don't use that one.  That said, I'm going with Steve in that the hum is due to the cart/wiring and not the ZP3.  Without any input my ZP3 hisses.  With the headshell/cart installed I get a low hum while without the headshell installed I get a loud hum.

Here is an interesting paper that talks a little about phono stage noise and how it is a trade between fidelity and quietness:  http://www.co-bw.com/Audio_All_about_phono_preamp.htm

So, hum free my ZP3 is not.  But I don't hear it so I try not to think/worry about it.  I have a MM cart and I wonder if the MC carts might not have quite the hum issue?  One last thing.  I considered angled RCA adaptors but didn't go with them because some feel that the large hunk of brass can degrade the signal compared to a good interconnect end.  I just used longer cables.

RickVee, is your hum only (or mainly) out of the right channel?  Have you tried swapping the interconnects to see if the hum follows?  Or using different interconnects altogether?  I'm curious since I had a "bad" interconnect at one point.  I've opened my ZP3 and the RCA jacks are so rigidly installed and so basic that I think the odds are more in favor of a bad interconnect -- but one never knows.

Yeah, sounds like a Steve issue.  Let us know what he says!

Just got my ZP3 yesterday.  By itself it is pleasantly quiet connected to my CSP3.  However when I use the ZMC 1 there is a bothersome 60hz type hum.  I've have tried the usual interconnect changes and grounding options with little effect.  I do know id the ZMC is within 12" of the ZP3 the hum will get louder but once outside of 12" it does not improve.  

With a MM cart the ZP3 is nice and quiet but add the ZMC even if not connected to the TT and there is the hum.  Not real noticeable when music is playing but loud enough to be irritating during quiet passages.

Anyone else have this issue with just a ZMC step up?

I hear no excessive noise when the ZMC is not in the system so I assume it is the source of the hum.  Although there may be another source for the interference with the ZMC.  The ZMC seems very well shielded so it is surprising that something external to it is the source?

I have a ZMC1 in front of the ZP3 and the extra gain does make the hum more noticeable but not bothersome with music. But as the ZP3 and Rachael are getting more hours the enjoyment level is going up and up.
Loving these products, just need to get the present speakers up for sale and get the Monoliths before the sale ends….happy listening, Chris.

What are the ''El Caminos'' I have seen mentioned on the forums and also in the talk of the last Decfest. As a bassist, I need to have a good extended bottom end. I don't expect to hear/feel my Moog Pedals as I do/did on stage but I need the extension down there.