Wonder if there is a grounding issue somewhere?
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I agree with elizabeth, it has to be static.
With the volume control turned all the way down it must be a hell of a static charge.
What is the the percentage of humidly in the room?
Belt drive TT?
What material is the platter made of?
What are you using for a TT platter mat? You might try a cork one.
What method are you using to clean your records? Are you wiping them dry with a cotton cloth? That will build up a good static charge.
I have done everything to avoid static in the system. I'm quite sure it is not static.
It has to be static. No other possible thing.
I agree with elizabeth, it has to be static.
Simple enough to test. If its static then it will pop even before the stylus touches down, the instant its close enough for a charge to zap across the gap. Otherwise it will pop only after gliding over the vinyl to finally drop into the groove.
And so as Richard Dawson so often proclaimed..... "Survey says......"
How do explain the OP said the volume control is turned all the way down? How is the POP signal voltage getting through the all the way turned down volume control?
Did you recently install this cartridge?
If you are using separate components, is the preamp new to your system?
You are sure with low and high volume that you are not hearing any irregularities?
Pending those answers, eliminating static is not too hard: 1. Get rid of fabric turntable mats and replace with either a cork mat which you can likely get from Amazon or otherwise from U-Turn Audio. OR you can get a Herbies Way Excellent II Turntable Mat. 2. Get a Zerostat and use it.
I have the SOTA Nova with SME V and Ortofon Quintet Black. Ortofon ST7 step up and Sutherland DUO Phono amp into Bryston SP3 preamp. Everything is grounded, air is humid. I use Furutech static discharger, I don't brush my records, and I have a static drain on the turntable. Not much chance of static here! Even if it were static, how could it pass the volume control which is turned all the way down?
Does the pop still occur if the mute function of the SP3 is engaged prior to and at the time the stylus hits the record?
Also, by any chance do any of the components in the system, such as a powered subwoofer, have a signal-sensitive auto-standby feature?
Finally, and this is just a hunch, if you are still using the Plinius Odeon amplifier you mentioned in a post a few months ago you might try changing the setting of its ground-lift switch to the opposite of what it is currently set to. It would be prudent, though, to turn the amp off and wait about 30 to 60 seconds before changing that setting.
Disconnect the turntable ground and see if it happens. Next try a different cartridge. Very Weird. It has to be sending a signal through the ground assume your volume is all they way down when it is all the way down. Is there any signal at all with the volume all the way down. If there is just a little it is the cartridge.
Did you look through the owner manual of the SME V arm? Check out "515 Audio Lead" found on page 12.
I assume the OP connected the single ground from the arm 5 pin din connector cable to the ground lug on each phono amp.
I assume there is no other grounding connections from the arm. Only the connection from the arm to the two phono preamp’s ground lug.
Sutherland DUO Phono amp
The units came with a few hours on them with loading/gain set at 47/40, the default, which worked well for my Phasemation PP-2000 MC Phono Cartridge. Loading/Gain adjustment is easy and accessed by unscrewing the top plates. Don’t forget to set loading and gain values the same on each chassis.Is it possible the OP has the gain set too high on the phono preamps?
If we are to assume the problem is not caused from static electricity then it must be signal voltage generated from the stylus hitting, contacting, the groove of the record.
Is the loud POP heard through both the left and right speakers? That might be good to know.
Is it possible the POP voltage gain is large enough it is over driving the Line input circuitry of the Bryston SP3 preamp?
I assume the volume control on the Bryston preamp is not a motorized pot. Some how the high gain voltage POP is getting past the volume control circuitry and getting to the power amp’s inputs.
Jim (Jea48), thanks for providing the links. Not sure if you noticed that the OP is using a step-up transformer between the turntable and the dual chassis Sutherland phono stage, with the phono stage presumably being used in moving magnet mode. Here is the manual for the step-up:
It shows that a single ground wire should connect the turntable to the ground terminal on the SUT, and another ground wire should be connected from that terminal to the phono stage. Which in this case would mean that a single wire should be used to connect that terminal of the SUT to the ground terminals of both phono stage chassis.
Before commenting further I'll await the OP's response to the questions that have been raised since his last post, as well as confirmation of how the ground connections are implemented between the turntable, SUT, and phono stage.
Thanks Al (almarg).
Here is what the SP3 manual says about the volume control.
D: VOLUME CONTROL / ROTARY ENCODER Continuous rotary optical encoder for determining volume level as well as an input for most variable settings and other selections within both the System and Source menus.http://www.bryston.com/PDF/Manuals/300024[SP3].pdf
Do you know how those things work?
Is it possible a high level POP voltage spike would cause the circuitry for the volume control to screw up and pass the spike through onto the gain section of the preamp and out the outputs while still maintaining its’ minimum level setting?
Maybe a dumb question I wonder what would happen if the OP set the SP3 to a different Line level input and then conducted the same test. Nothing should happen right? No POPPING sound through the speakers, right?
That is unless somehow the POP voltage spike is traveling on the signal ground. Could that even happen?
The signal ground is not part of the circuitry of the volume control. Correct?
Not a dumb question at all about seeing if the pop occurs when a different input is selected. That would definitely be of interest, as would the answers to my questions one of which was about whether the pop disappears if the SP3 is muted. And yes, a grounding issue does seem conceivable.
The fact that the volume control utilizes a rotary optical encoder isn't particularly helpful, though, at least without detailed information on the circuitry that follows its photo-detector, both within the control and externally to it. That kind of control works by shining a LED near the circumference of a rotatable disk having a large number of radially-oriented slots through which the light can shine. As the control is rotated a photo-detector produces an output in the form of a pulse each time a slot moves in front of the LED, and subsequent circuitry utilizes the string of pulses to control how much attenuation is introduced, perhaps after first converting the number of pulses into a corresponding change in a DC voltage.
Everything is grounded properly as described in the manuals. I believe we have hit on something with the MUTE button though. There is no MUTE button on the front panel of the SP3 processor but when I select MUTE on the SP3 remote, the problem is solved completely. Now the problem is I don't want to have to go to the remote every time I use the turntable. I always thought volume all the way down was the same as mute. Apparently not. Anyone have any idea what is going on here?
In addition to the experiment Jim suggested, did you try this experiment I suggested earlier:
... if you are still using the Plinius Odeon amplifier you mentioned in a post a few months ago you might try changing the setting of its ground-lift switch to the opposite of what it is currently set to. It would be prudent, though, to turn the amp off and wait about 30 to 60 seconds before changing that setting.
While Bryston provides schematics at their website for many of their models, unfortunately they don’t for the SP3. And neither does hifiengine.com. But I took a look at the schematic for the SP1.7:
As is the case in many designs it appears that the muting function is accomplished with relays that short the various outputs to ground when the mute function is activated. It also appears that the outputs are AC coupled via 100 uF capacitors, which are "ahead" of the relays in the signal path. I would expect that the SP3 is similar in those respects. If perchance you have the ground-lift switch on the amp set to the lift position, while I can’t formulate a complete explanation I’m thinking that the issue might be related to the fact that with the switch in that position and no signal existing within the SP3 the AC coupling would allow the input of the amp to "float" to an uncontrolled and arbitrary level relative to its chassis and to AC safety ground and to the chassis and the circuit ground of the SP3, **if the muting relays are not activated.**
That may or may not have anything to do with the problem, of course, but intuitively it seems to me that it's a possibility. And in any event if you are using the Odeon the experiment I suggested is easy enough to do. Also, as Jim suggested contacting Bryston and describing your findings to them may be worthwhile.
Interesting that I have this happen too on my turntable but it only pops on my left speaker and not all the time. Only when I use the dust brush so I have to think it has to be static. Weird that it comes through when my amp is muted though.
I'm going to upgrade my table soon anyway and get a cork mat.
Try this, and it may seem simple. Move the stylus to the lead-in groove and before you lower it, move it just enough such that it touches down after the music has been cut into the vinyl. In other words, try lowering the stylus anywhere on the record where the music groove has already been cut.
This does not sound like a static issue to me ( but it could very well be an issue of high static charge). Does this happen with a wide variety of records or are you only hearing this wth one album?
My London Reference is very sensitive to landing and lift-off from the record and it has nothing whatsoever to do with static. I’ve seen this lead in pop noise also with my modified Denon 103.3 and it seems to happen more so with newer albums where the vinyl has a rim-lip, sometime I can see the stylus make a mechanical jump to land into the lead-in groove.
I found this on another site and this is what I’m referring to in my above post.
another author wrote:
“It seems that about 1 in ever 4 to 5 times I start a record when the stylus touches the lead-in groove it jumps a few grooves in to the first couple of seconds of the first song. I was wondering if this was normal because I do not remember my old Sony Direct drive doing this but my new table is alot more precises and sensitive? I did some Google searching and found this on Wikipedia "# Because of a slight slope in the lead-in groove, it was possible for the stylus to skip ahead several grooves when settling into position at the start of the recording."”.
I have no clear notion of what is going on, but I just wanted to point out that a static discharge can be very very high in voltage (thousands of volts or more, over the span of a few micro- or milliseconds), although vanishingly low in current. Therefore, I could imagine that such a discharge would pass right through a volume control, regardless of its setting.
Also, before one feels confident of having eliminated a static charge with fancy external gadgets, one ought to look at the following: Are you wearing leather soled shoes? Does the turntable sit over a wool carpet or the like? Is your body grounded? Very often the cause of static charge build-up is "us".
just an idea that the optical encoder is causing the noise, and most probably needs attention, check that all its connections are firm on the sub board and then to the main board . I am not sure that optical encoders when at min mute the signal, that’s why your problem is solved when mute is on. Do you have too much gain?