Technics SLD 202 - Can't get it to sound right

[hergest74]

I have re-calibrated my Technics SLD 202 exactly as advised but I just can't get my vinyl to sound right. At high levels of volume the sound kind of distorts as if there is a build up of fluff and loses detail, but less busy parts sound great. I have checked the Audio Technica AT440MLb stylus for dust build up and cleaned with the fine brush supplied with it, as well as dropping it on a magic sponge but it just doesn't sound right. Checked connections etc to no avail. The stylus was sounding great last time it was played. Even checked the alignment of the screws and tip of stylus with the Technics gauge.

As far as I know nothing has changed since last time I calibrated it except now I have made the additional adjustment to getting the level spot on with a spirit level. I haven't used the stylus long enough for it to have worn out.

[Edward Huggins]

It might not be the cartridge at all. Is your amplifier still sounding OK on other input sources?

[hergest74]

There is some cut out on L and R channels when panned in balance as well as intermittent cutting out switching between different modes (Phones/Tape/Radio etc) Its a Rotel RA-930AX. Perhaps years of dust and a little damp in teh old house have got into it a bit.

[Edward Huggins]

Try some SERVISOL 10 cleaner on the input selector switch.

[hergest74]

Although I have ordered some Servisol as it sounds good to have around for other uses in audio it is def not the amp as it sounds fine with the tape/cd player selected. Its a real mystery as I have set it up precisely as it should be, checked levels, dust, clean stylus and no apparent damage but it sounds dreadful now. Sounds like overloading at busy musical bits and sometimes muffled but again, no dust. All cables, earth and phono connections are fine.

[Edward Huggins]

O.K. This could be a chipped stylus. oxidised cartrirdge connections (removee and spray and reconnect these), a failing cartridge or a problem in the RIAA phono pre-amp section of your quite old Rotel amp.

[PaulR]

I take it that you have checked the tracking force?

One part of the amp you cannot check by using other inputs is the phono pre-amp. Could you beg , steal or borrow an external pre-amp to try?

[hergest74]

The tracking force is precise as I have bought a special gauge. I have a Samson Servo 170 in my upstairs music strudio as well as a NI Komplete audio interface on my pc if that could work ?

[PaulR]

I am afraid I am not familiar with the Samson amplifier so I cannot advise on its suitability. Others may have more information. The instruction manual says it will accept inputs of any level so it may be worth a try.

Edit I have just seen that Edward suggested the phono pre-amp in the post before mine. Apologies to him for not noticing this.

[jamesperrett]

The Samson Servo 170 is a power amplifier so won't work with a magnetic cartridge and I don't think that the NI audio interface will have a magnetic cartridge input. My bet is on the tracking force being too low - the manufacturer's lowest limit is usually optimistic and you are better off going towards the higher end of the recommended range.

[Radio Wrangler]

The Samson Servo series amplifiers are just line level input, so they are not sensitive enough to work with a magnetic cartridge, nor do they have the RIAA frequency response shaping needed for replay. It's just a power amplifier.

I've used them at work as power drivers for simulating vehicle power supplies with alternator faults. They're OK, fairly cheap, but can be blown up! Though they were wrking into distinctly unfriendly loads.

David

[hergest74]

Originally Posted by jamesperrett

The Samson Servo 170 is a power amplifier so won't work with a magnetic cartridge and I don't think that the NI audio interface will have a magnetic cartridge input. My bet is on the tracking force being too low - the manufacturer's lowest limit is usually optimistic and you are better off going towards the higher end of the recommended range.

Its def not the tracking force as it is set to it's limit, and I have even tried a little above and it still sounds bad. Also, I know the exact force it should be as it's always performed at it's optimum at that setting so it wouldn't be any different.

[PaulR]

I think the only way to proceed is by substitution.

The fault is in the stylus, cartridge or amplifier pre-amp. If you cannot borrow another amp or record deck then you could maybe try buying a cheap magnetic cart to start with. They are available from ebay at around £12. Phono pre amps are from under £20.

Go first with whichever your head tells you is most likely to be at fault. If it was mine I would probably start with the cartridge, but then you seem to be fairly confident in it. There is really no magic answer.

[hergest74]

Ok, I have inspected the stylus with a magnifier and its covered in grey crud, with single hairs sticking up here and there. I can't even see the stylus tip it's that bad. For the life of me I can't clean it with the brush provided or dropping it on the magic sponge (as recommended online) neither seem to work. Further down some of the cantilever shows some white mottling, almost mildew looking. The house is old and gets damp and I haven't played the turntable for quite a few months if that has any bearing. The turntable doesn't have it's perspex cover either so it's open to the elements.

Can anyone suggest a more harsher way of cleaning that won't damage the stylus, perhaps some alcohol solution or similar ?

[PaulR]

Isopropyl alcohol is a very good cleaner but I wonder whether you could do with a new stylus. The crud and hairs sound like fungus caused by dust and damp.

[stevehertz]

I bought a really strong 'jeweller's' magnifier to enable me to see the stylus in all its glory. Looking at it with the naked eye and a strong magnifier is shockingly different, the amount of detritus that you think doesn't exist, does, not to mention nodules. By that means I'd eliminate the stylus for sure.

[hergest74]

Originally Posted by stevehertz

I bought a really strong 'jeweller's' magnifier to enable me to see the stylus in all its glory. Looking at it with the naked eye and a strong magnifier is shockingly different, the amount of detritus that you think doesn't exist, does, not to mention nodules. By that means I'd eliminate the stylus for sure.

It really is covered, you can't see the stylus and the muck won't come off. I have looked online what a stylus should look like clean and this doesn't resemble it. I have looked into Onzow ZeroDust Stylus Tip Cleaner which seems to work a treat but it's not cheap. It is supposed to last for life though.

[PaulR]

If the stylus is removable you could soak it in IPA for a while then try a stylus brush. If that doesn't get it off then I think it is there to stay. if it is some sort of fungus/mould that would at least kill it.

[hergest74]

Is it not worth investing in the gel cleaner as it is supposed to remove anything ?

[stevehertz]

Originally Posted by hergest74

It really is covered, you can't see the stylus and the muck won't come off. I have looked online what a stylus should look like clean and this doesn't resemble it. I have looked into Onzow ZeroDust Stylus Tip Cleaner which seems to work a treat but it's not cheap. It is supposed to last for life though.

Well there's your problem then; a caked stylus. But in the first post you seem to reject it being the problem as you say you haven't used it long enough to have worn out? Well maybe not worn out, but caked in detritus. It will sound awful. I use Audio Technica cleaning fluid to clean mine. It takes time, but particles do come off eventually, you have to stick at it.