I'm using a Grado Prestige Red on a Technics EPA501 arm, and I've never been able to get it aligned quite right. The Grado is a little too wide in the back to move all the way back in the mounting slots on the headshell, which is where it needs to be to get the proper overhang.
Since I have an extra cartridge, I just tried grinding a bit of the plastic off of the top rear edge and was able to get it properly aligned finally, which really helped with the inner groove distortion (not so much mistracking on sibilant vocals and such, but more a constant, woolly, almost tube-like distortion on most vocals, harmonica, horns and anything else in that general range, mainly on the center channel and increassing dramatically in the last inch or so on each side) that's been bothering me for a while, but became WAY more obvious since I upgraded to a tube amp.
Basically, if you look at the photo below, I ground the plastic top behind the mounting holes down by about 1mm, and rounded the back corners of the flanges that the holes are in.
The one thing that worries me is that there is a small spot (maybe .25mmx1mm) on the top where I ground through the plastic, but I can't see if there is metal uderneath or if I've actually made a little hole into the body of the cartridge. Should I cover it with something? What?
Other than that it seems fine, I was able to get it pretty much dead on, the distortion is almost gone even on the most challenging passages I've played so far, and I had no trouble getting the VTA or weight set (no surprise there). It DOES seem to be slightly quieter, but that could be because I'm using a different (older) cartridge, or it could be my imagination, or it could have been the distortion making it sound a bit louder before.
I guess I don't have any specific questions, just wanted to throw this out to the poeple on here with a lot more experience than me, and see if there was anything I should be aware of, any risks involved in reshaping a cartridge body that aren't immediately obvious to me, etc. My ears can live with a less than perfect sound, I just don't want to damage my records.
Since I have an extra cartridge, I just tried grinding a bit of the plastic off of the top rear edge and was able to get it properly aligned finally, which really helped with the inner groove distortion (not so much mistracking on sibilant vocals and such, but more a constant, woolly, almost tube-like distortion on most vocals, harmonica, horns and anything else in that general range, mainly on the center channel and increassing dramatically in the last inch or so on each side) that's been bothering me for a while, but became WAY more obvious since I upgraded to a tube amp.
Basically, if you look at the photo below, I ground the plastic top behind the mounting holes down by about 1mm, and rounded the back corners of the flanges that the holes are in.
An externally hosted image should be here but it was not working when we last tested it.
The one thing that worries me is that there is a small spot (maybe .25mmx1mm) on the top where I ground through the plastic, but I can't see if there is metal uderneath or if I've actually made a little hole into the body of the cartridge. Should I cover it with something? What?
Other than that it seems fine, I was able to get it pretty much dead on, the distortion is almost gone even on the most challenging passages I've played so far, and I had no trouble getting the VTA or weight set (no surprise there). It DOES seem to be slightly quieter, but that could be because I'm using a different (older) cartridge, or it could be my imagination, or it could have been the distortion making it sound a bit louder before.
I guess I don't have any specific questions, just wanted to throw this out to the poeple on here with a lot more experience than me, and see if there was anything I should be aware of, any risks involved in reshaping a cartridge body that aren't immediately obvious to me, etc. My ears can live with a less than perfect sound, I just don't want to damage my records.
UPDATE:
It seems like the distortion has shifted to the outer grooves now. I don't even know what to think. This is all happening over maybe 1mm of cartridge movement on the headshell. I've pretty much tried swapping out everything at one point or another - different stylus, different cartridge, different speakers, different amp. Basically everything in the vocal range that is centered in the mix sounds like it's being played through a tube amp that is distortiing, with a blanket thrown over the speakers, everything that is happening to the right and left of the mix sounds relatively good, especially percussion. Flutes, saxophone, and voice are the worst.
I've tried aligning to different null points, etc. etc.
This has been a problem for at least a year.
It seems like the distortion has shifted to the outer grooves now. I don't even know what to think. This is all happening over maybe 1mm of cartridge movement on the headshell. I've pretty much tried swapping out everything at one point or another - different stylus, different cartridge, different speakers, different amp. Basically everything in the vocal range that is centered in the mix sounds like it's being played through a tube amp that is distortiing, with a blanket thrown over the speakers, everything that is happening to the right and left of the mix sounds relatively good, especially percussion. Flutes, saxophone, and voice are the worst.
I've tried aligning to different null points, etc. etc.
This has been a problem for at least a year.
If the Grado is a bit more front than ideal,you can align it using a good alignment protractor by turning it on the headshell so that the mounting screw on the outside is slightly more front than the inner one.When the cartridge is correct on the protractor tighten both screws.In this position,the cartridge will not be parallel to the headshell,but it will be correct on the alignment protractor.This will help much to lower the distortion.
I was doing that for a while, but I've managed to fidget the unmodified cartridge back farther and I think it's pretty much dead on now, at least well withing the margin of error on my print-out protractor. I think shaving off the plastic on the old one may have made it a little too light to match up well with my arm.
Another surprising thing I discovered this afternoon was that the antiskate, which I've been setting at just over 1.5 to match the tracking force, actually wants to be closer to 2.5. I only recently found a record in my collection with enough space after the trail-off to actually set the antiskate properly, and it turns out it doesn't hold its position until the antiskate is at around 2.48 with the TF at 1.5.
Not what I expected at all, although my first cartridge years ago (some sort of Shure) actually specified an antiskate of something like 3 with a TF of 2.
Anyhow, I'm wondering now if maybe I've worn out my stylus a lot sooner than usual since I switched to working entirely from home this summer and have had more time to play records. In the past I needed to change it every 10-12 months, but this one is jsut under 5 months old. Unfortunately, I don't have a microscope powerful enough to check for wear, but I have a new stylus on order, so hopefully when I try it out things will sound better.
Another surprising thing I discovered this afternoon was that the antiskate, which I've been setting at just over 1.5 to match the tracking force, actually wants to be closer to 2.5. I only recently found a record in my collection with enough space after the trail-off to actually set the antiskate properly, and it turns out it doesn't hold its position until the antiskate is at around 2.48 with the TF at 1.5.
Not what I expected at all, although my first cartridge years ago (some sort of Shure) actually specified an antiskate of something like 3 with a TF of 2.
Anyhow, I'm wondering now if maybe I've worn out my stylus a lot sooner than usual since I switched to working entirely from home this summer and have had more time to play records. In the past I needed to change it every 10-12 months, but this one is jsut under 5 months old. Unfortunately, I don't have a microscope powerful enough to check for wear, but I have a new stylus on order, so hopefully when I try it out things will sound better.
Another thought:
Back when I worked at a record store, I got a bottle of the cheap stylus cleaning fluid we carried and didn't think much of it. I was also pretty bad about cleaning the stylus regularly back then. Recently, I looked at the label and noticed that the fluid (this stuff ) contains alcohol, which I've heard can damage the material used for the cantilever pivot. So maybe cleaning my stylus more often has actually made it wear out faster (albeit not the same kind of wear I assumed).
Again, the distortion I'm getting is not really characterized by mistracking on sibilance and other high frequency sounds, it's more in the midrange and is kind of a fuzzy, almost warm (but not in a good way) distortion, mainly on vocals, but usually not affecting anything else in the mix. Almost like the singer's voice is running through an overdriven guitar amplifier or something.
Back when I worked at a record store, I got a bottle of the cheap stylus cleaning fluid we carried and didn't think much of it. I was also pretty bad about cleaning the stylus regularly back then. Recently, I looked at the label and noticed that the fluid (this stuff ) contains alcohol, which I've heard can damage the material used for the cantilever pivot. So maybe cleaning my stylus more often has actually made it wear out faster (albeit not the same kind of wear I assumed).
Again, the distortion I'm getting is not really characterized by mistracking on sibilance and other high frequency sounds, it's more in the midrange and is kind of a fuzzy, almost warm (but not in a good way) distortion, mainly on vocals, but usually not affecting anything else in the mix. Almost like the singer's voice is running through an overdriven guitar amplifier or something.
Is it possible that what sounds to be distortion to your ears is actually the cartridge playing back the upper mid and treble at a higher level than the mid and lows.
When this occurs in a cartridge it does often sound the way you describe it. How do I know? I own a few garrott decca cartridges.
The cure with the garrott deccas is to alter the input resistence that the cartridge sees in the preamp input. Your preamp presumably has a standard 47k ohms impedance on the disc input. You can lower this by adding a resistor between the + and _ on each channel of the pre amp input. Try 47k ohms first of all which lowers the input impedance of the preamp to 23.5k. If that reduces the "distortion" too much try a higher value of resistor. If you want more reduction try 25k ohms.
You may find this makes a big difference as it normally helps or cures the problem with forward sounding cartridges.
Don
When this occurs in a cartridge it does often sound the way you describe it. How do I know? I own a few garrott decca cartridges.
The cure with the garrott deccas is to alter the input resistence that the cartridge sees in the preamp input. Your preamp presumably has a standard 47k ohms impedance on the disc input. You can lower this by adding a resistor between the + and _ on each channel of the pre amp input. Try 47k ohms first of all which lowers the input impedance of the preamp to 23.5k. If that reduces the "distortion" too much try a higher value of resistor. If you want more reduction try 25k ohms.
You may find this makes a big difference as it normally helps or cures the problem with forward sounding cartridges.
Don
I have a stereo microscope that goes up to about 40x, which seems OK for checking for dirt on the stylus, even though it's nowhere near strong enough to look for wear.
This morning I had the local print shop print me the Stephanolouv arc protractor for the Technics epa-100 (which has the same geometry as the 500), checked the scale with a machinist's rule, had it laminated, came home and checked my alignment with it. Lo and behold, when I've got things lined up really well at the inner null point, by the outer null point it's drifted off by just about -2mm from where it should be. Instead of resting at the center of the outer null point crosshair, the stylus is right on the line of the little circle of the crosshair. Maybe the tonearm was installed a little off at the factory or has shifted a bit from decades of use by people who weren't as careful as me. Anyhow, I set it up so that it's just a fraction of a millimeter over at the inner null point and about 1.5mm under at the outer null point, and am going to have to call that the best I can do. Sometime I'll take it to a professional and have them check it, but for now it's as well aligned as I'm going to get it with the tools I have available.
That's interesting advice about the input impedence on the preamp. The Scott 299c is definitely a more forward amp than my previous one, so it makes sense that if this were my issue to begin with the new amp would make it more objectionable. I'd rather not modify the amp itself (vintage gear and all), but I should be able to put something together on perfboard and patch it in line between the turntable and the preamp input, right? I could even build one channel with a trimpot, tune that channel to my liking, measure the value of the trimpot and build a final two-channel version with quality resistors. I'd rather add a little more cable and some more plugs to my signal path that mess with my reciever right now, especially since I'm not sure yet that it's the problem. Definitely great advice, though, I'll try it for sure!
This morning I had the local print shop print me the Stephanolouv arc protractor for the Technics epa-100 (which has the same geometry as the 500), checked the scale with a machinist's rule, had it laminated, came home and checked my alignment with it. Lo and behold, when I've got things lined up really well at the inner null point, by the outer null point it's drifted off by just about -2mm from where it should be. Instead of resting at the center of the outer null point crosshair, the stylus is right on the line of the little circle of the crosshair. Maybe the tonearm was installed a little off at the factory or has shifted a bit from decades of use by people who weren't as careful as me. Anyhow, I set it up so that it's just a fraction of a millimeter over at the inner null point and about 1.5mm under at the outer null point, and am going to have to call that the best I can do. Sometime I'll take it to a professional and have them check it, but for now it's as well aligned as I'm going to get it with the tools I have available.
That's interesting advice about the input impedence on the preamp. The Scott 299c is definitely a more forward amp than my previous one, so it makes sense that if this were my issue to begin with the new amp would make it more objectionable. I'd rather not modify the amp itself (vintage gear and all), but I should be able to put something together on perfboard and patch it in line between the turntable and the preamp input, right? I could even build one channel with a trimpot, tune that channel to my liking, measure the value of the trimpot and build a final two-channel version with quality resistors. I'd rather add a little more cable and some more plugs to my signal path that mess with my reciever right now, especially since I'm not sure yet that it's the problem. Definitely great advice, though, I'll try it for sure!
Reason why it does not align on both null points is I believe because you have to pull the cartridge slightly forward and find an angle on the headshell where it is correct on both points.Similar alignment is true for rega tonearms too.You have nothing to lose trying.If not,I would align correctly on the inner null point.
There's no indication of the phono input impedence in the manual, but a cursory google search turned up a paper on modifying the similar 222c and the measured impedence of the phono ins on that was in the 48-49k, and based on that I'm going to say a nominal 47k impedence is very, very likely.
Different issue, but in the earlier post where I mentioned the big discrepancy between the common-sense anti-skate setting (equal to the tracking force) vs. the amount of antiskate needed to make the arm stop gliding on a blank disc (just under 1 gram heavier than the tracking force), which seems more likely to be accurate? I know there's disagreement on whether the glide test is accurate.
Thanks for all the advice!
Different issue, but in the earlier post where I mentioned the big discrepancy between the common-sense anti-skate setting (equal to the tracking force) vs. the amount of antiskate needed to make the arm stop gliding on a blank disc (just under 1 gram heavier than the tracking force), which seems more likely to be accurate? I know there's disagreement on whether the glide test is accurate.
Thanks for all the advice!
Almsot all records. It's a lot worse with records that have female vocalists, male vocalists with a pinched singing style (i.e. Neil Young, Van Morrison, some Sun City Girls stuff, that type of thing), horns, violin, basically anything in that range. I haven't checked too carefully about how consistent it is in starting at the exact smae place because I don't want to replay the same part of the LP more than once in succession, since there's a good chance this is a worn stylus (new one's on the way, but that won't stop me fidgeting with other stuff until it arrives and I can try that).
One really unintuitive thing about it is that female singers (and flute) seem to lose a lot of the presence and get muddy, especially during loud passages (across the disc, but worse near the center) while male singers seem to be more thin and strident as they sing louder.
I double checked briefly through a cheap DJ mixer and headphones and the inner groove distortion, at least, is present through that also, so that's probably not related to the preamp.
The main reason I'm hesitant to blame stylus wear is that the stylus I've got now is so young. I've been using the same Grado cartridge type for about 4 years now, and I've never had a stylus need replacing before 12 months, but this one's only been on for around 5 months. Maybe I'm just noticing the degradation a lot sooner because the new amp is more responsive and much brighter than my old one.
One really unintuitive thing about it is that female singers (and flute) seem to lose a lot of the presence and get muddy, especially during loud passages (across the disc, but worse near the center) while male singers seem to be more thin and strident as they sing louder.
I double checked briefly through a cheap DJ mixer and headphones and the inner groove distortion, at least, is present through that also, so that's probably not related to the preamp.
The main reason I'm hesitant to blame stylus wear is that the stylus I've got now is so young. I've been using the same Grado cartridge type for about 4 years now, and I've never had a stylus need replacing before 12 months, but this one's only been on for around 5 months. Maybe I'm just noticing the degradation a lot sooner because the new amp is more responsive and much brighter than my old one.
Panicos K said:
Is this true on arc protractors? FOr some reason I thought it wasn't, this may be my problem, then. I've never used one before, only classic two-point protractors (generally Stevenson, since it's really close to the factory-recommended null points for my arm). I'll give it a shot.
Yes I believe that it can happen with arc protractors too.Ideally your cartridge(not necessarily the headshell)should be correct at both null points,and the stytlus able to follow the arc on the other protractor.If you do this and the problem remains,it will be easier to suspect the stylus.Although the EPA501 is said to have good bearings,have you noticed any play,or even to be too tight?
I once had an Alphason tonearm and its protractor had two null points and the arc.That was really very helpful.
I once had an Alphason tonearm and its protractor had two null points and the arc.That was really very helpful.
There may be a tiny bit of play at the bearings, but it's equal to or less than the amount I've felt on every other Tehcnics turntable I've checked for play on - not enough to SEE any movement, bt enough that there is a slightly audible (but again, less so than lesser Technics arms) rattle when I gently move it along the line of the arm. I've wondered about that before.
Anyhow, I haven't done any fine work with the protractor since my last post, but jsut to see what would happen, I moved the cartridge out to about the mid point of the headshell (it was almost all the way back previously) to see how that would affect its alignment at the null points on the arc protractor, and now, when it is on the inner null point it is about twice as far behind the outer point as it was before. Maybe it's just bcause I've only done a rough check and haven't really aligned it properly at the new position, but it does seem like moving it out on the headshell is making things worse.
It's hard to make an accurate check since the spinlye blocks the arm from lowering all the way when it's centered, but eyeballing it the best I can, it looks like when the cart is all the way back in the headshell, the overhang is still about 17mm, where it's specced at 15mm. Weird.
Anyhow, I haven't done any fine work with the protractor since my last post, but jsut to see what would happen, I moved the cartridge out to about the mid point of the headshell (it was almost all the way back previously) to see how that would affect its alignment at the null points on the arc protractor, and now, when it is on the inner null point it is about twice as far behind the outer point as it was before. Maybe it's just bcause I've only done a rough check and haven't really aligned it properly at the new position, but it does seem like moving it out on the headshell is making things worse.
It's hard to make an accurate check since the spinlye blocks the arm from lowering all the way when it's centered, but eyeballing it the best I can, it looks like when the cart is all the way back in the headshell, the overhang is still about 17mm, where it's specced at 15mm. Weird.
Well, I spent an hour messing with it and couldn't get it any better than it is when the cartridge is backed off all the way.
I actually reseated the turntable on its plinth on a huch (I took it out to do a simple repair a couple of months ago and undoubtedly didn't get it seated exactly how it was from the factory). There was just a tiny bit of play, maybe 1mm, and by experimenting with that I was able to get a little closer, but no aduible difference.
Maybe the new amp just doesn't mask existing wear on my records as much as the old one did (it's definitely brighter and a lot more detailed) and now that I'm aware of it I notice it on the other amps I've checked it against. Whatever it is, things sound terrible. I'm playing the A side of Blonde On Blonde and it sounds like he's singing through a kazoo.
EDIT: I'm going to do a sanity check with the Sundazed mono reissue of Jefferson Airplane Takes Off that I've only played twice. Any tracking distortion I hear on that is almost certainly coming from my turntable.
I actually reseated the turntable on its plinth on a huch (I took it out to do a simple repair a couple of months ago and undoubtedly didn't get it seated exactly how it was from the factory). There was just a tiny bit of play, maybe 1mm, and by experimenting with that I was able to get a little closer, but no aduible difference.
Maybe the new amp just doesn't mask existing wear on my records as much as the old one did (it's definitely brighter and a lot more detailed) and now that I'm aware of it I notice it on the other amps I've checked it against. Whatever it is, things sound terrible. I'm playing the A side of Blonde On Blonde and it sounds like he's singing through a kazoo.
EDIT: I'm going to do a sanity check with the Sundazed mono reissue of Jefferson Airplane Takes Off that I've only played twice. Any tracking distortion I hear on that is almost certainly coming from my turntable.
Yeah, even from the opening of the record, all of the vocals and cybals sound very distorted. Bass and low mids sound excellent on this one, though.
Maybe I'll a/b between a CD and an LP of the same album or something. I have a Sleep album on vinyl and LP, simultaneous releases. Should be a good control.
Maybe I'll a/b between a CD and an LP of the same album or something. I have a Sleep album on vinyl and LP, simultaneous releases. Should be a good control.
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