Pioneer PL-12D turntable

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Discussion

dave123456

Original Poster:

1,961 posts

150 months

Friday 2nd June 2023
quotequote all
Evening,

Recently bought my second one of these, oddly the sound is pretty crap.

It sounds overly bassy, a bit underwater.

I’ve swapped the head shell over and it’s not that, any thoughts?

Thanks

Lucid_AV

431 posts

39 months

Saturday 3rd June 2023
quotequote all
You've had one of these before, so you know that they can sound pretty reasonable. This one then is an outlier. Is that about the sum of it?

The deck is (obviously) used. Did you have a listen before buying, or just pick it off the classifieds/eBay? Just trying to ascertain if this is something to do with transport and set-up or the deck was sold needing some TLC.

The watery sound is generally a speed issue. Look up Wow and Flutter. The speed is fluttering rather than the once-per-revolution or longer variation in speed that is the wow part. First things first, new belt. Even is the vendor told you it had a recent belt change, if the deck has been sat for some length of time then the belt can kink around the motor spindle.

Next, lube the motor and the spindle bearing. Light machine oil, not SAE30 biglaugh and not tonnes of it. It's possible to get a strobe disc and strobe light to check the running speeds for 33 and 45.

Now the cartridge and stylus. Just do a sanity check on the cartridge wiring. There two grounds and two signal wires, and they're colour coded so that you can tell left from right and signal from ground. Then have a look at the stylus tip: is there still a tip, and does it look like a little floor mop because it's covered in crud. If so, clean that off.

Has he cartridge been installed correctly. You really need a cartridge alignment protractor for this to make sure it's aligned in the headshell correctly. If the sound is still too bassy (and you know for sure that the cartridge and stylus are tip top), then I'd look at the tracking weight first. Check the range recommended for the cartridge. Start at the lighter end, and if you get mistracking (skipping) or distorting in louder passages of the music then try increasing by 0.1g increments. Don't forget to adjust the anti-skate setting to match.

Too much bass can be caused by other things such as the turntable sitting on the same shelf as the speakers or the Vertical Tracking Angle (VTA) of the cartridge having the back too low. There is no adjustment for the height of the pivot of the tonearm. If the cartridge is too tall for the arm then you'll need to either shim the front to change the angle, or replace it for one that better suits the deck.

Old PL12Ds are fairly bullet proof but not totally. Bits wear out. There should be some foam in the suspension springs to stop them vibrating (ringing), but after a decade or two the foam starts to break down. There are various DIY tips what to use. I've heard of people cutting up the foam speaker bungs, or car sponges, even bits of fibreglass loft insulation. The other service item is the rubber bungs that isolate the motor mounts. They go hard and need replacing by new squidgy jobs. This is a bit like suspension bushes in cars, but not nearly so difficult or as expensive to replace.

Let us know how you get on.

thebraketester

14,423 posts

141 months

Saturday 3rd June 2023
quotequote all
Do you have a MM/MC setting on your pre amp? Is it set correctly?

dave123456

Original Poster:

1,961 posts

150 months

Saturday 3rd June 2023
quotequote all
Thank you for the responses.

I have another identical turntable so have ruled out the head shell.

The MM / MC is correct too.

I’ll look into the new belt, what sort of oil is recommended for the motor and spindle?

dave123456

Original Poster:

1,961 posts

150 months

Saturday 3rd June 2023
quotequote all
Having manually manipulated the rotational speed I’m pretty sure it’s not that. It’s almost like the signal wire can’t carry the higher frequency. Even with the treble turned up on the amp it still sounds capped.

I’m pretty sure most of the signal split is left / right channel on these so I’m puzzled.

To give the permutations I’ve ruled out so far:

Tried the head shell on my other set up, sounds fine.
Amp is used to power a cd player and a Bluetooth receiver bother sound fine.
Tried more than one record on it, all sound muted from a treble.

Bit of a loss.

Lucid_AV

431 posts

39 months

Saturday 3rd June 2023
quotequote all
dave123456 said:
Having manually manipulated the rotational speed I’m pretty sure it’s not that. It’s almost like the signal wire can’t carry the higher frequency. Even with the treble turned up on the amp it still sounds capped.

I’m pretty sure most of the signal split is left / right channel on these so I’m puzzled.

To give the permutations I’ve ruled out so far:

Tried the head shell on my other set up, sounds fine.
Amp is used to power a cd player and a Bluetooth receiver bother sound fine.
Tried more than one record on it, all sound muted from a treble.

Bit of a loss.
Some of your descriptions are a bit confusing. For example, "Amp is used to power a cd player and a Bluetooth receiver". The only way for that to happen is if the amplifier has power outlets which means that the mains plugs of other devices connect to a switched mains loop-thru. That's more common with US versions of Hi-Fi receivers and mass market amps because the US uses a much smaller mins plug with only two pins. UK 3-pin mains plus just take up too much room. Anyway, the bottom line on that is that an amp doesn't power a CD play or BT receiver. It simply receives and amplifies the signal, so not the same thing you're describing.

For this reason, your description of underwater isn't what I'd first associate with that phrase. I think for you it just means a lack of treble and not the flutter of speed variations that's often described using the same term. What we appear to be dealing with then is this lack of treble resulting in the sound having too much bass.

If by "swapped the headshell" you mean you've changed the cartridge for a known good one off the other TT, then what's left is the tonearm and lead-out wires terminating in the RCA (phono) plugs. There's damage to them leading to an increase in capacitance, and that in turn creates an electric signal filter which tanks the treble and so results in an over-bassy sound. Have you swapped out the RCA cable from the deck to the amp at all?

From what I've seen, the PL12D tonearm wires from the arm tube come out under the deck and are then soldered to a small board. This then provided the connection for the thicker coax cables that wire in turn to the RCA sockets on the rear of the deck. You might want to have a look under the deck to check that wiring through.

It would be unusual to get dry joints on both RCA plugs at the same time, but not impossible. Normally, one would go first leading to a loss of treble on one channel only. Anyone competent would investigate and fix that, but also re-solder the connections from the arm wires and through to the plug too.

Lucid_AV

431 posts

39 months

Saturday 3rd June 2023
quotequote all
Lucid_AV said:
Some of your descriptions are a bit confusing. For example, "Amp is used to power a cd player and a Bluetooth receiver". The only way for that to happen is if the amplifier has power outlets which means that the mains plugs of other devices connect to a switched mains loop-thru. That's more common with US versions of Hi-Fi receivers and mass market amps because the US uses a much smaller mins plug with only two pins. UK 3-pin mains plus just take up too much room. Anyway, the bottom line on that is that an amp doesn't power a CD play or BT receiver. It simply receives and amplifies the signal, so not the same thing you're describing.

For this reason, your description of underwater isn't what I'd first associate with that phrase. I think for you it just means a lack of treble and not the flutter of speed variations that's often described using the same term. What we appear to be dealing with then is this lack of treble resulting in the sound having too much bass.

If by "swapped the headshell" you mean you've changed the cartridge for a known good one off the other TT, then what's left is the tonearm and lead-out wires terminating in the RCA (phono) plugs. There's damage to them leading to an increase in capacitance, and that in turn creates an electric signal filter which tanks the treble and so results in an over-bassy sound. Have you swapped out the RCA cable from the deck to the amp at all?

From what I've seen, the PL12D tonearm wires from the arm tube come out under the deck and are then soldered to a small board. This then provided the connection for the thicker coax cables that wire in turn to the RCA sockets on the rear of the deck. You might want to have a look under the deck to check that wiring through.

It would be unusual to get dry joints on both RCA plugs at the same time, but not impossible. Normally, one would go first leading to a loss of treble on one channel only. Anyone competent would investigate and fix that, but also re-solder the connections from the arm wires and through to the plug too.
Oil: 3in1 fan oil. You're looking for something without additives; a monograde synthetic.


Watcher of the skies

548 posts

40 months

Saturday 3rd June 2023
quotequote all
It might seem a silly question, but have you connected the turntable to the phono input on your amplifier, or failing that are you using a phono stage?

Lucid_AV

431 posts

39 months

Saturday 3rd June 2023
quotequote all
Watcher of the skies said:
It might seem a silly question, but have you connected the turntable to the phono input on your amplifier, or failing that are you using a phono stage?
He has another of the same make and model, so you'd presume he understands what to do with this second deck. Also, if the TT signal was fed directly to a line in then (a) it would be a heck of a lot quieter and (b) there's be virtually no bass, nearly all treble. RIAA equalisation is an EQ curve that restores bass and cuts the treble to compensate for how vinyl has to me cut on the lathe when producing the master required for duplication.

dave123456

Original Poster:

1,961 posts

150 months

Saturday 3rd June 2023
quotequote all
Lucid_AV said:
Some of your descriptions are a bit confusing. For example, "Amp is used to power a cd player and a Bluetooth receiver". The only way for that to happen is if the amplifier has power outlets which means that the mains plugs of other devices connect to a switched mains loop-thru. That's more common with US versions of Hi-Fi receivers and mass market amps because the US uses a much smaller mins plug with only two pins. UK 3-pin mains plus just take up too much room. Anyway, the bottom line on that is that an amp doesn't power a CD play or BT receiver. It simply receives and amplifies the signal, so not the same thing you're describing.

For this reason, your description of underwater isn't what I'd first associate with that phrase. I think for you it just means a lack of treble and not the flutter of speed variations that's often described using the same term. What we appear to be dealing with then is this lack of treble resulting in the sound having too much bass.

If by "swapped the headshell" you mean you've changed the cartridge for a known good one off the other TT, then what's left is the tonearm and lead-out wires terminating in the RCA (phono) plugs. There's damage to them leading to an increase in capacitance, and that in turn creates an electric signal filter which tanks the treble and so results in an over-bassy sound. Have you swapped out the RCA cable from the deck to the amp at all?

From what I've seen, the PL12D tonearm wires from the arm tube come out under the deck and are then soldered to a small board. This then provided the connection for the thicker coax cables that wire in turn to the RCA sockets on the rear of the deck. You might want to have a look under the deck to check that wiring through.

It would be unusual to get dry joints on both RCA plugs at the same time, but not impossible. Normally, one would go first leading to a loss of treble on one channel only. Anyone competent would investigate and fix that, but also re-solder the connections from the arm wires and through to the plug too.
To confirm I’m running a standard uk set up. The amp has inputs for a cd and a Bluetooth receiver, both of which sound fine.

Your deduction re my definition of underwater is correct, I meant muffled and lacking the clarity of bass.

As you say it is more likely one of the cables on the tone arm as both channels are affected.

And I am using the phono inputs

dave123456

Original Poster:

1,961 posts

150 months

Saturday 3rd June 2023
quotequote all
Fixed!

Thank you for suggestions all. It was a RCA connection within the TT.

When purchased it was sold as having new RCAs, the wire was new but the solder was poor. So resoldered and now sounds spot on.

Lucid_AV

431 posts

39 months

Saturday 3rd June 2023
quotequote all
Glad I was able to pointbyoubin the right direction.

Stuff like this makes one wonder why the previous owner did this but never tested the deck properly.

Lucid_AV

431 posts

39 months

Saturday 3rd June 2023
quotequote all
Did he do anything else to 'improve' the turntable? smashrofl You might want to go through the whole thing just to see.