Speaker hiss

Discussion in 'Audio Hardware' started by Oliver Meyer, Oct 5, 2019.

  1. Oliver Meyer

    Oliver Meyer In Audio Heaven Up Here Thread Starter

    Location:
    Virginia Beach
    This has been an issue for a few weeks now. I happened to notice it when I lowered the gain settings on the phono amps and the volume was in turn higher
    I started with everything disconnected except the power amp.
    Just power cord and speakers connected, there was no hiss.
    I then connected the pre amp power cord and XLR. A very low hiss that doesn't change with volume.
    I then connected the phono amps power cords and RCA from phono outs to preamp in. Still a low hiss except now on phono input it changes with volume.
    I tried a different phono amp and had the same result.
    I connected the TT with no change.
    I have tried cheater plugs with no change.
    I've tried different cables with no change.
    At this point I'm at a loss.
    Maybe it's the power amp!
    Is the phono just amplifying the hiss?
    I have noticed that there is a hum coming from the power amp. I assume it's the transformer. Could this be the source of the problem?
    Either way listening to vinyl has to be done at a low volume to negate the hiss.
    I've raised the gain on the phono amps to 58 so I don't have to have the volume so high which helps.
    Any ideas?

    Sent from my iPhone
     
  2. Thorensman

    Thorensman Forum Resident

    How does it sound?
    Gain is high on phono.
    If you lift tonearm off record at normal
    Listening volume hiss is probably
    Gone.
    Only audible at high levels ,
    Levels you would not listen at.
    Gain obviously high, as cartridge outpur low, low compared to cd
     
  3. Oliver Meyer

    Oliver Meyer In Audio Heaven Up Here Thread Starter

    Location:
    Virginia Beach
    Sounds like a hiss
    Gain was low which meant higher volume to listen at regular levels.
    Hiss is there regardless of tonearm. His is there even without the TT connected.
    Even if the hiss isn't audible the amp is still trying to amplify it.
    I heard it between changing records with volume at a level I normally listen to.
     
  4. Ontheone

    Ontheone Forum Resident

    Location:
    Indianapolis
    SS or tube gear? If a mix can you indicate which of your components use tubes?
     
  5. Oliver Meyer

    Oliver Meyer In Audio Heaven Up Here Thread Starter

    Location:
    Virginia Beach
    It's all SS
     
  6. hagtech

    hagtech Forum Resident

    Location:
    Oahu
    Hiss is normal when using a phonostage! This is only a problem if it is louder than groove noise. When you play an LP at normal listening level, you can hear hiss during lead-in or between songs, right? Queue the arm up. Does it get quieter? If so, then residual hiss level from phonostage is not a problem.
     
  7. Ontheone

    Ontheone Forum Resident

    Location:
    Indianapolis
    Some hiss is inevitable with a very high gain component - phono stage. But should only be audible at a high volume and the vinyl surface noise should completely overwhelm it.
     
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  8. chervokas

    chervokas Forum Resident

    You're going to have hiss when you have gain. It's really just a question of how much. And you're using these two levels of preamp gain -- the phono pre gain and the line stage gain. But you said you didn't much notice the hiss when you were using more phono stage gain and less line stage gain. Go back to doing it that way. Sounds like that was a better setup in terms of noise levels.
     
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  9. Oliver Meyer

    Oliver Meyer In Audio Heaven Up Here Thread Starter

    Location:
    Virginia Beach
    My only concern with this is that the Sutherlands are supposed to be so quiet. I feel like something is wrong somewhere.
     
  10. Ontheone

    Ontheone Forum Resident

    Location:
    Indianapolis
    Speaker sensitivity?
     
  11. Oliver Meyer

    Oliver Meyer In Audio Heaven Up Here Thread Starter

    Location:
    Virginia Beach
    86dB (2.83V / 1m)
     
  12. Oliver Meyer

    Oliver Meyer In Audio Heaven Up Here Thread Starter

    Location:
    Virginia Beach
    This of course could just be my OCD
     
  13. chervokas

    chervokas Forum Resident

    Gain staging is a bit of an art. If you get better signal to noise ratio with more gain from the phono stage, a stronger signal to the line stage, and less gain/more attenuation from the line stage, well, that's the best gain staging to use.
     
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  14. RiCat

    RiCat Forum Resident

    Location:
    CT, USA
    Looking at your first post and using it as the stepladder. "I then connected the pre amp power cord and XLR. A very low hiss that doesn't change with volume." This is the first appearance of the hiss. And it does not change with volume control changes. This is where you need to investigate the cause of the hiss. The preamp and or it's connection to the amp are the cause of the hiss. Just for reference My Bryston amp and pre (with a phono stage) have no hiss and are dead quiet at all volume positions. There should not be a hiss when the pre and amp are connected and the pre has nothing attached to any input. Balanced circuits require a input sensitivity setting adjustment on the amp. Checking your amp, there is a switch for balanced/unbalanced preamp input. Is it in the balanced position? If not switch it to balanced and the hiss should go away. If it is correctly set try using the unbalanced RCA connections and setting the switch to unbalanced. Did the hiss change? What you describe is just what is experienced when using the balanced option and not properly selecting the matching input sensitivity on the amp. As you say this has recently started then something has changed from before to after. If after checking that you have correct settings for sensitivity the hiss is still there, I would suggest taking the preamp to your dealer or a friends house and connecting it to a different amp with just speakers attached. If you have hiss then it might be indication to have it looked at by a qualified tech. Please remember you have isolated the source of the hiss very early on. All the other steps just made it more obvious.
     
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  15. Strat-Mangler

    Strat-Mangler Forum Resident

    Location:
    Toronto
    Phono = (some degree of) hiss
     
  16. Gibsonian

    Gibsonian Forum Resident

    Location:
    Iowa, USA
    Do you have input attenuators on your amplifier?

    Is so reduce output by rotating attenuators ccw.
     
  17. chervokas

    chervokas Forum Resident

    This is interesting advice though I gather that the OP is using Primare gear designed to interoperate for pre and power. I've also, in a budget home project studio set up, had relatively high levels of his with some cables that disappeared with others. Never figure out why that way, but swapping out the bad XLR/balanced cable solved the problem.
     
  18. Oliver Meyer

    Oliver Meyer In Audio Heaven Up Here Thread Starter

    Location:
    Virginia Beach
    I've tried all of the above before with the same results.
    I've tried different XLR phono cables etc.
    The hiss is always there just much louder with the phono amps connected.
    There is a mechanical hum coming from the power amp. Maybe this is the problem
     
  19. head_unit

    head_unit Forum Resident

    Location:
    Los Angeles CA USA
    No, that is NOT the cause of the hiss (it's a different problem) because
    As @RiCat notes, at least some hiss is coming from your preamp. And/or, inducing in the cables between preamp and power amp. If you only connect the cables, without the preamp, do you hear hiss? (It's a bit of an unfair test since the cables are unterminated. But as an engineer trying to debug, I'd still want to know).
    - Connect the preamp, you said steady hiss, not changing with volume. This is with NO cables connected to the preamp except power cord and cables to power amp? Is the hiss there with the preamp OFF? (if so it implies something inducting or leaking in, or some kind of grounding problem).
    - What about other inputs? Do you hear hiss from your Oppo? What if you connect other inputs? Like plug the Oppo into different inputs?
    - Have you thought about asking Primare?
     
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  20. Phil Thien

    Phil Thien Forum Resident

    Location:
    Milwaukee, WI
    MM phono preamps amplify the incoming signal about 100x, as much as 1000x in the LF regions (due to the RIAA curve). MC preamps even more.

    I live in a large city, nearby (within 2-3 miles) broadcast towers. I have six or seven FM signals above 10db, with one of them at 0db (so a lot of powerful transmitters nearby).

    This results in my phono stage picking-up all sorts of noise. Sometimes it sounds like a radio station. Other times, though, it can just sound like hiss. Which I get depends a lot on the time of day (radio signals travel further after dark).

    My preamp (a Bellari, inexpensive but pretty decent bit of USA-made kit that includes a phono section) uses a 15vdc wall wart. I've replaced that with an 8xAA battery pack. I've also added ferrite chokes to all cables coming into the Bellari, including the one from the battery pack.

    The result is an extremely quiet system. With no turntable connected, there is no hiss until the preamp is cranked way up (past 3 o'clock). With the turntable connected, I do get a faint hiss when the preamp gain is @ approx. 12 o'clock, which would be a very loud listening session.

    If I were you, given what you've described, I'd try to relocate the Sutherland in relation to anything producing an audible hum (your amp). That may be inducing something in the Sutherland. Just try to give yourself enough cable and with the gain on the preamp set loud enough that you can hear some hiss, carefully/slowly move the Sutherland around and see if the level of hiss changes.

    Also consider trying a different cable between the Sutherland and the preamp. Finally, consider adding a choke on the cable from the Sutherland right where it enters the preamp.
     
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  21. chervokas

    chervokas Forum Resident

    I think the phono amp is operating normally. High gain phono, you're going to have some hiss. The hiss with the preamp connected to the power amp only, that to me from your description seems higher than one might expect.
     
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  22. Tom Littlefield

    Tom Littlefield Forum Resident

    Location:
    New Hampshire, USA
    I have the 20/20 and yes if I turn my amp up to beyond my normal listening level I do hear a hiss.

    But at normal levels it is very quite.
     
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  23. Nephrodoc

    Nephrodoc Forum Resident

    I had a moderate amount of hiss in my system. I just attributed it to the phono, amp and high sensitivity speakers. Setting the phono to the lowest gain was the best sounding, and had the least amount of hiss. At the time I had Ortofon OM30> Parasound JC3 jr>Peachtree Nova 65>Zu Omen.

    When I upgraded my amp to the Raven Blackhawk, the hiss is now barely audible. All the other components stayed the same. Not sure why the tube integrated is quieter, but in my system the reduction in hiss was huge.
     
  24. Oliver Meyer

    Oliver Meyer In Audio Heaven Up Here Thread Starter

    Location:
    Virginia Beach
    What do you have the gain set to?
     
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  25. Oliver Meyer

    Oliver Meyer In Audio Heaven Up Here Thread Starter

    Location:
    Virginia Beach
    I agree. I think the problem is in the amps. The hum from the power amp could be the problem. I will reach out to Primare see what they say.
     
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