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Old 8th August 2006, 12:17 PM   #1
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Default distortion with LPs

In my pursuit of building a complete DIY system I have now reached the turntable and phono amp stages, but I am feeling a bit frustrated with the sound and not sure what to do first.

Currently I have a very simple phono pre amp which uses 1 LM833 op amp and a direct drive turntable, (akai) and a 20yr old A and R cambridge P77 cart, with a new stylus.

All of these will be replaced but here is my question and I realise it is probably to vague to give a definte answer but any opinions are appreciated.

Even on new records I hear a degree of distortion (pronounced graininess) on the strong mid frequency sounds, especailly vocal and sharp piano notes, of course old records are much worse.

The tracking is right so thats not the problem, though it is better by a bit if I set the tracking a little on the heavy side.

Is the distortion likely to be the phono amp overloading, poor interconnects from the TT to the pre amp or the cart or all of the above. Basically I am going to build a new Phono amp first.

Additionally in loud/complex passages the whole sound becomes somewhat confused, once again what is the most likely suspect here.

Overall I like the sound of LPs but I feel I m probably very sensitive to mid range distortion and it took my ages to eradicate it from the rest of the CD based system so I sure don't want to go back to square one again.
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Old 8th August 2006, 12:45 PM   #2
infinia is offline infinia  United States
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Hi
I know you said "replaced the stylus", but your description of the sound says... dodgy stylus to me. Been there before. Maybe think about buying a new cartridge 20 yrs is a long time.
Can you trouble shoot more by hooking TT up to an old receiver?
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Old 8th August 2006, 01:16 PM   #3
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I'd suggest taking your turntable to another known good system to isolate the problem. If it sounds good, the problem's in the phono stage, if it sounds bad, it's the turntable.

For the turntable, I would carefully set up with alignment guages and a test record as a first step and very carefully set VTA, then look at arm and spindle bearings so that it's running as well as possible to standard spec.
Mid-range distortion traced to the turntable suggests to me arm bearings or cartridge suspension if the geometry is set up correctly.
After that, and only when the deck is running well, my next thought is that cartridges have improved enormously in the last 20 years and a mm Goldring or mi Grado etc. could be a big upgrade

regards, Jeff
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Old 8th August 2006, 01:26 PM   #4
sreten is online now sreten  United Kingdom
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Hi,

could be a dodgy stylus as suggested, especially if the new stylus
is a generic replacement, which vary from half decent to rubbish,
A&R stopped making cartridges a long time ago.

Seems to me you are asking a lot from what could be a not very
good turntable regarding the ability to resolve complex passages.
For this you need a good turntable fitted with a decent arm.

sreten.
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Old 8th August 2006, 01:26 PM   #5
SY is offline SY  United States
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All good advice. One question: when you say "new stylus," is it actually new or is it 20 year old NOS?
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Old 9th August 2006, 12:37 PM   #6
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The stylus is new, but I am thinking the cart may not be as good as new, maybe as suggested the suspension is cactus. I should say though that my system is very high res so all problems show up pretty obviously and I am probably a bit picky.

Would the suspension cause this mid range distotion though, the upper highs are very nice and the bass very strong.

I have found that changing all the cables on the rest of the system did remove a lot of mid range grain, so I wonder if that is worth trying too.

I don't expect much from the phono pre-amp but I don't have any other at this oint to compare it too other than the one in my Rotel 820B, but it isn't as good as this one.

I'm learning towards a Goldring 1042 cart but I wonder how it handles worn records, I know from experience that some carts are far better than others here and as I have a lot of LPs from when I was a teenager that are less than perfect this is important.
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Old 9th August 2006, 01:32 PM   #7
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Hi, I've not tried the Akai turntables , but the Goldring cartridges work very nicely in other Japanese DDs of the same period. They love '70s and 80's music.

Just which one you choose I think depends on how good the arm is and i found the 1012GX sounded as good as the 1042 in the original arms that came with those decks. It's possible that the more exact stylus profile of the 1042 needs an arm of rega rb250 quality to give it's best (??).
They do reward careful setting up and are sensitive to VTA some kind of vertical adjustment is an advantage.
regards, Jeff
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Old 9th August 2006, 09:25 PM   #8
karlw is offline karlw  United States
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I had a similar problem years ago with a Grado cartridge. A few records would play OK but many would sound distorted. Then I finally sprung for a Shure V15 type V MR and my problems went away. I'm still using that cartridge today (10 years later) with one stylus replacement. I did buy the V15 Type Vx before they stopped making them, but I'll save that one until the older one gives out. My plan is to be able to play records at least for another 20 years...
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Old 10th August 2006, 09:38 AM   #9
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Thanks Guys

Can anyone tell me what the differnec is between the various 1000 series goldring carts, other than price of course?
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Old 10th August 2006, 10:46 AM   #10
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Hi, they are all the same body and generator, but the stylus profile changes.
The 1006 is an elliptical whist as you go up the range you get variations on the Geiger profile. I've only used the 1012 and 1042 but found both amazingly good at the price.

It's an owner-replaceable stylus so you can upgrade the basic 1006 to a 1042.

Jeff
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