Record-player audio distortion. - UK Vintage Radio Repair and Restoration Discussion Forum

bsrman · 29th Oct 2005, 3:18 pm

My BSR UA-14 (or 15?) record changer tends to distort (especially as the record progresses towards the centre)...this is a very "scratchy" distortion which increases as the music gets louder. Soft sections don't distort. Actually when I purchased it there was no cartridge in it. So I fitted it with a more modern stereo cartridge. The distorted sound seems to be accompanied by a kind of sound reproduction similar to that of a stylus clogged up with dust. All too often I am lifting the pick-up arm off the record to blow the dust off the needle only to find that there isn't any gathering of dust at all! Furthermore, on some records there seems to be a very heightened recording sound/play sound that overpowers the music itself in softer sections which can be quite distracting. In other words, the "play sound"? is too high in relation to the MUSIC itself. Further still, there is sometimes a "ghosting" of neighbouring tracks of the record. All in all, the sound just doesn't seem to be particularly "direct". Anyone have any ideas of what the problem(s) might be? Thanks

Nickthedentist · 29th Oct 2005, 4:07 pm

Hello!
Several things could be responsible:

(1) The stylus is damaged (worn or chipped). If it's a turnover type, does the other side sound any better?

(2) The tracking force ("playing weight") is wrong, probably too light. Does (temporarily) taping a pound coin to the end of the arm make any difference?

(3) The arm bearings are stiff. Does it seem to swing left and right and up and down very freely?

(4) The cartridge is faulty. This can occur even with new or NOS cartridges. Try another one if you've got a second player you can rob one from.

(5) The amplifier is faulty. This can introduce distortion that sounds uncannily like stylus/cartridge problems, but it should not make the signal-to-noise ratio worse (which I think is what you're getting at in your description).

Let us know how you get on,

Nick.

Nickthedentist · 29th Oct 2005, 4:30 pm

One other thing. If you installed the cartridge yourself, is the angle at which it tracks the record correct? And are the cartridge's connecting wires dressed properly, i.e. not rubbing on the record as it spins?

Nick.

Stewart · 29th Oct 2005, 5:33 pm

I'm with Nick on this one - sounds to me as if the tracking weight is set way too low. These changers just weren't made to track at low weights - the arm bearing (and the autotrip mechanism) will play havoc at anything less than about 4 grams I should think. Did you adjust the weight after you put in a new cartridge?

Pye once used a modified version of the UA15 tracking at 2-2.5 grams in their 1005 Achoic Projection stereo with the Pye / CBS Butterfly pick-up - My own view is that this was misguided to say the least - the final set up being able to detect a butterfly landing on a flower on the other side of the planet - I assume that's why they named it so?

Be warned that the poor tracking caused by running a pick-up at too light a playing weight can cause much more record damage than one set too high.

bsrman · 30th Oct 2005, 11:30 am

Many thanks, Stewart and Nick! I will go through all your problem shooting pointers. Regarding the stylus, well it is fairly new and shows no VISIBLE signs of wear.

NICK:

As you will know, the original cartridges of UA 14's were ceramic and the stylus flipped over from the very FRONT of the head-shell. The newer cartridge I have is more slim-line and is flipped from UNDERNEATH the head-shell. Can't remember what the cartridge is (as I threw away the box it came in), but I know that the slylus is embossed with "LP.S ST17D". (33's and 45's are played on one side and 78's are played on the other).

Since I changed over to the new cartridge, I lightened up the weight of the tone-arm by notching the weight-spring (which is located underneath towards the rear or the tone-arm) out first to the 6th hole but later found tracking to be very bad so notched it back to the 5th hole to add more weight. The newer cartridge wasn't actually fitted by myself--it was fitted by hi-fi technicians. As knowledgeable as they were about later period turntables, they admitted having very limited knowledge on this period of turntable (and record-changers in general) but said they'd do their best in servicing the deck for me. Apparently most of the servicing guys who knew about all this kind of stuff retired years ago, and the fact that I live in a small country like New Zealand also doesn't help the matter.

You were talking about the "arm-bearings" possibly being stiff....so are these bearings hard to see? Where exactly are they located? Are they easy to get at? Well I have always wondered if there is ample play in sideways/up and down play of the tone arm....it's real hard to tell with certainty...I do kind of get the feeling that maybe there isn't quite enough play. How exactly can this arm play be 'measured' as such?? All I know is that it's not TERRIBLY stiff but it also is nowhere as free as the play of a sophisticated modern arm.

You also mentioned the possibility of the cartridge being faulty. Actually I have always suspected this too. From what I was told by the hifi shop here, the cartridge WAS actually meant for a BSR (but a much later model than a UA14).

Another good point you had was regarding the angle by which the cartridge tracks the record and if it is CORRECT. I have wondered this too--especially concerning if it's tilted FOWARD enough. You know, I had been reading somewhere that audiophiles disdain record-changers primarily for the fact that as each respective record falls, the ANGLE of the cartridge in relation to the record CHANGES and therefore supposedly reduces sound quality. In other words, a record being played from say the 10th stacked level will sound not as good as the very 1st record dropped onto the platter (if you see what I mean).

STEWART:

Thanks for your good advise about over-light arm weights being more damaging on records than over-heavy weights...quite surprising really, I never would have thought that before!...but it does kind of make sense now that you have bought it up. I can imagine that a too light an arm weight would cause the stylus to gauge away at the record track edges rather than if it was bedding itself nicely into the groove. You say that these record changers just weren't meant to track at such light weights and you were suggesting nowhere under 4 grams in arm weight. So how exactly does one measure the arm weight on these older decks? What is the device needed? Would you also happen to have a photo of the Pye 1005 Achoic Projection stereo with the butterfly pick-up? I'd be real interested to see it!

Many thanks again to you both--Mike

Nickthedentist · 30th Oct 2005, 11:46 am

Quote:

Originally Posted by bsrman

Since I changed over to the new cartridge, I lightened up the weight of the tone-arm by notching the weight-spring (which is located underneath towards the rear or the tone-arm) out first to the 6th hole but later found tracking to be very bad so notched it back to the 5th hole to add more weight.

Try making the playing weight even greater, i.e. move the spring back to the 3rd or 4th hole. If that makes no difference at all, put it back where it was. Also, do try the old trick of temporarily taping a heavy coin to the cartridge-end of the arm, just to see what happens.

Quote:

Originally Posted by bsrman

You were talking about the "arm-bearings" possibly being stiff....so are these bearings hard to see? Where exactly are they located? Are they easy to get at? Well I have always wondered if there is ample play in sideways/up and down play of the tone arm....it's real hard to tell with certainty...I do kind of get the feeling that maybe there isn't quite enough play. How exactly can this arm play be 'measured' as such?? All I know is that it's not TERRIBLY stiff but it also is nowhere as free as the play of a sophisticated modern arm.

This is a difficult one, there's no easy way of measuring it other than by "feel", i.e. how it compares with a similar but working deck. At the risk of being told off by other people here, I would spray a little WD40 on the moving bits under the arm, and a little more on the bits under the deck that move with the arm. Make sure you use it sparingly, and don't get any on the drive components (motor pulley, idler wheel or inner surface of the turntable). Then work the arm back and forth and up and down a few times and try again. If this improves matters, it would be worth cleaning and oiling properly (quite tricky but not impossible).

Quote:

Originally Posted by bsrman

You also mentioned the possibility of the cartridge being faulty. Actually I have always suspected this too. From what I was told by the hifi shop here, the cartridge WAS actually meant for a BSR (but a much later model than a UA14).

It's probably one of the late 60s/early 70s ones made by BSR themselves, and should be compatible enough. Have you got another one you could substitute, perhaps borrowed from another player?

Quote:

Originally Posted by bsrman

Another good point you had was regarding the angle by which the cartridge tracks the record and if it is CORRECT. I have wondered this too--especially concerning if it's tilted FOWARD enough. You know, I had been reading somewhere that audiophiles disdain record-changers primarily for the fact that as each respective record falls, the ANGLE of the cartridge in relation to the record CHANGES and therefore supposedly reduces sound quality. In other words, a record being played from say the 10th stacked level will sound not as good as the very 1st record dropped onto the platter (if you see what I mean). )

I see exactly what you mean. But unless its WAY out, it shouldn't be a problem in simple record player like yours.

One final thought - make sure that the wires that exit the pickup arm under the deck aren't stopping the arm from moving sideways freeely. This can sometimes happen if they've been disturbed and are wrongly routed.

Nick.

paulsherwin · 30th Oct 2005, 12:39 pm

Mike, the distortion you describe sounds like classic compliance distortion to me. This happens when the stylus doesn't follow the groove correctly for some reason. All pickups do this to some extent, even very expensive hifi units. Old autochanger decks do it quite a lot. If you're used to listening to music from digital sources like CDs this distortion may be very obvious to you. Some listeners seem to be much more sensitive to it than others.

As Nick has pointed out, too low a tracking weight will make any compliance distortion very much worse, so you should investigate this first.

Good luck, Paul

Nickthedentist · 30th Oct 2005, 12:49 pm

Quote:

Originally Posted by paulsherwin

Mike, the distortion you describe sounds like classic compliance distortion to me.

Good point, Paul.

This can also happen if the rubber stylus mounting has perished and become stiff - which is why it's quite common for a turntable to sound awful when dragged out of the loft, even though it was sounding perfect when it was put there a few years previously. But I've only ever noticed this deterioration with magnetic cartridge styli, never ceramic ones.

mumbles · 30th Oct 2005, 2:39 pm

I had this with an old fifties stereo juke box. Apart from all the above, it could be the type of record you are trying to play with that stylus. Some of the stereo type cartrideges will not play mono records correctly due to the shape of the needle. Also vice versa for mono records. On stero records I found there were two different type of grooves between early and later ones. You should be able to see this with a magnifying glass. I went through all the records and eventually loaded the box with with records that looked the same groove type that played ok.

Also, the angle at which the stylus tip meets the record. For an auto changer - does the top record play okay opposed to the bottom one? If it's a single play deck you could experiment the easy way fist. Cut a piece of card to the shape of the turntable mat and place it underneth the mat - thus highering the record and altering the angle

bsrman · 31st Oct 2005, 12:08 pm

Thanks all for your help...

Nick:
Yes I have tried the coin trick before. The thing is that when I have tried to put additional weight on the arm to make it track better, a kind of play noise comes into effect almost as if something is rubbing or something. It's quite hard to explain really. I might just have to end up trying out another cartridge on it at some stage.

Mumbles:
Yes, there seems to be utterly no difference in sound irregardless of what record on the stack is being played (at least by MY perception anyway). Very intesting too about the 2 types of stereo groove...I never knew that.

Andrew_Keith · 31st Oct 2005, 2:02 pm

Hi Bsrman, I am in the position of having a hi-quality cd player on my system, and also hi-quality turntable (Technics SL1210) i can honestly say that i find listening to vinyl far more enjoyable than cds. The music is warmer and more involving than cds which have a more clinical sound quality to them. Yes vinyl does have its own distortions, but providing the cartridge is set up properly (tracking force etc) and stylus and records are kept clean i never find this an issue.

Regards.

mumbles · 31st Oct 2005, 5:05 pm

Hi Bsrman

Does sound like a cartridge/stylus issue so maybe worth trying another. Guess you are sure the cartridge output exactly matches the amp input spec? I have a Quad preamp which allows you to switch to different input settings etc. After listening to cd, when I plug a deck in, I tend to pick the brightest sounding setting on the input and the records sound sort of okay but scratchy on treble in parts. On a different impedence, more bassy but clear. I then realise, that's probably how they used to sound and how I used to listen.

I had about 5 jukeboxes, and none had any real adjustment on the arm apart from the weight tension spring hooked to a different hole. So each box ended up with a different stylus, and I had to work out which records were likely to play on whatever. Mono grooves look quite wide. On those horrible thin floppy warped records they made in the 80's, the record sufaces were almost smooth all the way across. Guess by then everyone was using a magnetic cartridge which was pretty much standard on hi-fi separates etc and the auto changer was dead. Maybe the grooves weren't so deep either and that's what made them look different. I dunno, but they were a problem for some older jukes.

peter_sol · 31st Oct 2005, 5:34 pm

Hi. In your first post you mention play sound louder than recorded sound
Maybe you are talking about rumble or a knocking sound caused by the idler wheel

What type of record player or system are you usingTo play this deck through and do you get the so called play sound when the arm lands ie. before the music starts? as I suspect that what you are complaining about may either be normal as compared to hifi turntables or indeed may even be worn records.

Just some things to think about.

Regards

Peter.

GMB · 31st Oct 2005, 6:50 pm

No-one seems to have mentioned bias compensation. If the bias is wrong then it can sound pretty bad. Check that the stylus isn't being pulled sideways. Bias problems usually change with the angle of the arm so if it's worse/better near the end of the record then that is the big clue.
I used to have one that certainly had this problem until I attacked the crude spring arrangement that supplied an excessively heavy bias.

Nickthedentist · 31st Oct 2005, 7:19 pm

Quote:

Originally Posted by GMB

No-one seems to have mentioned bias compensation.

Very true, but I've never come across a popular autochanger that has any method of adjustment, simply because the effects are too subtle to be worthwhile on a deck of this quality.

I can recall reading a well-respected 1960s HiFi magazine in which the author said that as far as he could see, the only noticeable advantage of a bias compensation device was that if the machine was accidently jogged, the stylus was more likely to drop back into the correct groove rather than one further towards the centre of the disc

Nick.

29th Oct 2005, 3:18 pm	#1
bsrman Retired Dormant Member Join Date: Sep 2005 Location: Dunedin, New Zealand Posts: 107	Record-player audio distortion. My BSR UA-14 (or 15?) record changer tends to distort (especially as the record progresses towards the centre)...this is a very "scratchy" distortion which increases as the music gets louder. Soft sections don't distort. Actually when I purchased it there was no cartridge in it. So I fitted it with a more modern stereo cartridge. The distorted sound seems to be accompanied by a kind of sound reproduction similar to that of a stylus clogged up with dust. All too often I am lifting the pick-up arm off the record to blow the dust off the needle only to find that there isn't any gathering of dust at all! Furthermore, on some records there seems to be a very heightened recording sound/play sound that overpowers the music itself in softer sections which can be quite distracting. In other words, the "play sound"? is too high in relation to the MUSIC itself. Further still, there is sometimes a "ghosting" of neighbouring tracks of the record. All in all, the sound just doesn't seem to be particularly "direct". Anyone have any ideas of what the problem(s) might be? Thanks

29th Oct 2005, 4:07 pm	#2
Nickthedentist Dekatron Join Date: Jan 2005 Location: Oxford, UK. Posts: 17,864	Re: Problem with Distortion Hello! Several things could be responsible: (1) The stylus is damaged (worn or chipped). If it's a turnover type, does the other side sound any better? (2) The tracking force ("playing weight") is wrong, probably too light. Does (temporarily) taping a pound coin to the end of the arm make any difference? (3) The arm bearings are stiff. Does it seem to swing left and right and up and down very freely? (4) The cartridge is faulty. This can occur even with new or NOS cartridges. Try another one if you've got a second player you can rob one from. (5) The amplifier is faulty. This can introduce distortion that sounds uncannily like stylus/cartridge problems, but it should not make the signal-to-noise ratio worse (which I think is what you're getting at in your description). Let us know how you get on, Nick.

29th Oct 2005, 4:30 pm	#3
Nickthedentist Dekatron Join Date: Jan 2005 Location: Oxford, UK. Posts: 17,864	Re: Problem with Distortion One other thing. If you installed the cartridge yourself, is the angle at which it tracks the record correct? And are the cartridge's connecting wires dressed properly, i.e. not rubbing on the record as it spins? Nick.

29th Oct 2005, 5:33 pm	#4
Stewart Retired Dormant Member Join Date: Jul 2003 Location: N.E. Surrey, UK. Posts: 361	Re: Problem with Distortion I'm with Nick on this one - sounds to me as if the tracking weight is set way too low. These changers just weren't made to track at low weights - the arm bearing (and the autotrip mechanism) will play havoc at anything less than about 4 grams I should think. Did you adjust the weight after you put in a new cartridge? Pye once used a modified version of the UA15 tracking at 2-2.5 grams in their 1005 Achoic Projection stereo with the Pye / CBS Butterfly pick-up - My own view is that this was misguided to say the least - the final set up being able to detect a butterfly landing on a flower on the other side of the planet - I assume that's why they named it so? Be warned that the poor tracking caused by running a pick-up at too light a playing weight can cause much more record damage than one set too high.

30th Oct 2005, 11:30 am	#5
bsrman Retired Dormant Member Join Date: Sep 2005 Location: Dunedin, New Zealand Posts: 107	Re: Problem with Distortion Many thanks, Stewart and Nick! I will go through all your problem shooting pointers. Regarding the stylus, well it is fairly new and shows no VISIBLE signs of wear. NICK: As you will know, the original cartridges of UA 14's were ceramic and the stylus flipped over from the very FRONT of the head-shell. The newer cartridge I have is more slim-line and is flipped from UNDERNEATH the head-shell. Can't remember what the cartridge is (as I threw away the box it came in), but I know that the slylus is embossed with "LP.S ST17D". (33's and 45's are played on one side and 78's are played on the other). Since I changed over to the new cartridge, I lightened up the weight of the tone-arm by notching the weight-spring (which is located underneath towards the rear or the tone-arm) out first to the 6th hole but later found tracking to be very bad so notched it back to the 5th hole to add more weight. The newer cartridge wasn't actually fitted by myself--it was fitted by hi-fi technicians. As knowledgeable as they were about later period turntables, they admitted having very limited knowledge on this period of turntable (and record-changers in general) but said they'd do their best in servicing the deck for me. Apparently most of the servicing guys who knew about all this kind of stuff retired years ago, and the fact that I live in a small country like New Zealand also doesn't help the matter. You were talking about the "arm-bearings" possibly being stiff....so are these bearings hard to see? Where exactly are they located? Are they easy to get at? Well I have always wondered if there is ample play in sideways/up and down play of the tone arm....it's real hard to tell with certainty...I do kind of get the feeling that maybe there isn't quite enough play. How exactly can this arm play be 'measured' as such?? All I know is that it's not TERRIBLY stiff but it also is nowhere as free as the play of a sophisticated modern arm. You also mentioned the possibility of the cartridge being faulty. Actually I have always suspected this too. From what I was told by the hifi shop here, the cartridge WAS actually meant for a BSR (but a much later model than a UA14). Another good point you had was regarding the angle by which the cartridge tracks the record and if it is CORRECT. I have wondered this too--especially concerning if it's tilted FOWARD enough. You know, I had been reading somewhere that audiophiles disdain record-changers primarily for the fact that as each respective record falls, the ANGLE of the cartridge in relation to the record CHANGES and therefore supposedly reduces sound quality. In other words, a record being played from say the 10th stacked level will sound not as good as the very 1st record dropped onto the platter (if you see what I mean). STEWART: Thanks for your good advise about over-light arm weights being more damaging on records than over-heavy weights...quite surprising really, I never would have thought that before!...but it does kind of make sense now that you have bought it up. I can imagine that a too light an arm weight would cause the stylus to gauge away at the record track edges rather than if it was bedding itself nicely into the groove. You say that these record changers just weren't meant to track at such light weights and you were suggesting nowhere under 4 grams in arm weight. So how exactly does one measure the arm weight on these older decks? What is the device needed? Would you also happen to have a photo of the Pye 1005 Achoic Projection stereo with the butterfly pick-up? I'd be real interested to see it! Many thanks again to you both--Mike Last edited by Darren-UK; 16th Jun 2007 at 3:00 pm. Reason: OT section removed.

30th Oct 2005, 12:39 pm	#7
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,967	Re: Problem with Distortion Mike, the distortion you describe sounds like classic compliance distortion to me. This happens when the stylus doesn't follow the groove correctly for some reason. All pickups do this to some extent, even very expensive hifi units. Old autochanger decks do it quite a lot. If you're used to listening to music from digital sources like CDs this distortion may be very obvious to you. Some listeners seem to be much more sensitive to it than others. As Nick has pointed out, too low a tracking weight will make any compliance distortion very much worse, so you should investigate this first. Good luck, Paul

30th Oct 2005, 2:39 pm	#9
mumbles Triode Join Date: Oct 2005 Location: Reigate, Surrey Posts: 13	Re: Problem with Distortion I had this with an old fifties stereo juke box. Apart from all the above, it could be the type of record you are trying to play with that stylus. Some of the stereo type cartrideges will not play mono records correctly due to the shape of the needle. Also vice versa for mono records. On stero records I found there were two different type of grooves between early and later ones. You should be able to see this with a magnifying glass. I went through all the records and eventually loaded the box with with records that looked the same groove type that played ok. Also, the angle at which the stylus tip meets the record. For an auto changer - does the top record play okay opposed to the bottom one? If it's a single play deck you could experiment the easy way fist. Cut a piece of card to the shape of the turntable mat and place it underneth the mat - thus highering the record and altering the angle

31st Oct 2005, 12:08 pm	#10
bsrman Retired Dormant Member Join Date: Sep 2005 Location: Dunedin, New Zealand Posts: 107	Re: Problem with Distortion Thanks all for your help... Nick: Yes I have tried the coin trick before. The thing is that when I have tried to put additional weight on the arm to make it track better, a kind of play noise comes into effect almost as if something is rubbing or something. It's quite hard to explain really. I might just have to end up trying out another cartridge on it at some stage. Mumbles: Yes, there seems to be utterly no difference in sound irregardless of what record on the stack is being played (at least by MY perception anyway). Very intesting too about the 2 types of stereo groove...I never knew that. Last edited by Darren-UK; 12th Jun 2007 at 1:24 am. Reason: Removed references to now-defunct ebay links.

31st Oct 2005, 2:02 pm	#11
Andrew_Keith Retired Dormant Member Join Date: Nov 2004 Location: Salford, Greater Manchester, UK. Posts: 150	Re: Problem with Distortion Hi Bsrman, I am in the position of having a hi-quality cd player on my system, and also hi-quality turntable (Technics SL1210) i can honestly say that i find listening to vinyl far more enjoyable than cds. The music is warmer and more involving than cds which have a more clinical sound quality to them. Yes vinyl does have its own distortions, but providing the cartridge is set up properly (tracking force etc) and stylus and records are kept clean i never find this an issue. Regards.

31st Oct 2005, 5:05 pm	#12
mumbles Triode Join Date: Oct 2005 Location: Reigate, Surrey Posts: 13	Re: Problem with Distortion Hi Bsrman Does sound like a cartridge/stylus issue so maybe worth trying another. Guess you are sure the cartridge output exactly matches the amp input spec? I have a Quad preamp which allows you to switch to different input settings etc. After listening to cd, when I plug a deck in, I tend to pick the brightest sounding setting on the input and the records sound sort of okay but scratchy on treble in parts. On a different impedence, more bassy but clear. I then realise, that's probably how they used to sound and how I used to listen. I had about 5 jukeboxes, and none had any real adjustment on the arm apart from the weight tension spring hooked to a different hole. So each box ended up with a different stylus, and I had to work out which records were likely to play on whatever. Mono grooves look quite wide. On those horrible thin floppy warped records they made in the 80's, the record sufaces were almost smooth all the way across. Guess by then everyone was using a magnetic cartridge which was pretty much standard on hi-fi separates etc and the auto changer was dead. Maybe the grooves weren't so deep either and that's what made them look different. I dunno, but they were a problem for some older jukes.

31st Oct 2005, 5:34 pm	#13
peter_sol Octode Join Date: Aug 2003 Location: Welwyn Garden City, Herts. UK. Posts: 1,906	Re: Problem with Distortion Hi. In your first post you mention play sound louder than recorded sound Maybe you are talking about rumble or a knocking sound caused by the idler wheel What type of record player or system are you usingTo play this deck through and do you get the so called play sound when the arm lands ie. before the music starts? as I suspect that what you are complaining about may either be normal as compared to hifi turntables or indeed may even be worn records. Just some things to think about. Regards Peter.

31st Oct 2005, 6:50 pm	#14
GMB Dekatron Join Date: Aug 2003 Location: near Reading (and sometimes Torquay) Posts: 3,099	Re: Problem with Distortion No-one seems to have mentioned bias compensation. If the bias is wrong then it can sound pretty bad. Check that the stylus isn't being pulled sideways. Bias problems usually change with the angle of the arm so if it's worse/better near the end of the record then that is the big clue. I used to have one that certainly had this problem until I attacked the crude spring arrangement that supplied an excessively heavy bias.