So, I bought one of those inexpensive miniature digital scales...

10seventy9

Active Member
The other day I was asking about a cart to make my turntable sound more open/bright, some of you might remember that.... well, I got the little scale in the mail today. I first off found out that either I didn't zero out my balance quite right when I first set up my table, or the numbers on my arm are off a little, but I was about 1/4 gram off of what the numbers actually said.

So, now that I know what my stylus actually weighs, I experimented a bit. I set it at 3 grams (Pioneer PL41 recommended to track at 2-3g) and had a listen to Supertramp's The Logical Song. Sounds "ok" but not what I remember this table sounding like when I was a kid/teenager. So, I back off 1/4 gram at a time until I hit 2 grams, and it's like the thing opened up and I have a completely different cartridge/stylus on it, HUGE, HUGE difference. Bigger, more open top and I think the bass sounds punchier, too. I am using a Shure/Radio Shack R47ED cart that I put an EVG/JICO N75EC stylus on at the recommendation of some folks here, so it's not a crap cart/stylus combo, but not exactly an exotic one either...


Long story short/TLDR... if you don't have one, buy yourself a small scale, it will make you very glad you did in short order. If anyone wants to know what scale I bought, feel free to PM me and I'll send you a link to it or I could post a link here, but I think that's not allowed if I remember right. I bought it off the auction site....
 
I agree. I have two that I use for my coin hobby. These things are not that expensive, so it's really worth dropping a few dollars just to check and make accurate adjustments.
 
Yeah, I didn't buy the one that's advertised as being for a turntable, I just bought a simple 8 dollar one, but it works great.

It's interesting how a cartridge/stylus sounds different at different tracking weights.
 
Just got one from that site for 6 bucks. Anxious to see how accurate these old tables still are.
 
The tracking weight isn't determined by the turntable, it's determined by the cartridge/stylus combination. I agree, cheapie digital scales are great and mine is dead accurate when checked with lab calibration weights.
 
The tracking weight isn't determined by the turntable, it's determined by the cartridge/stylus combination. I agree, cheapie digital scales are great and mine is dead accurate when checked with lab calibration weights.

Yeah, you're right. What I should have said was how accurate my cart/stylus are in relation to the weights. Good call.
 
Now now, you've should've plopped out the additional $50 for an audiophile grade scale. You've never get the blacker backgrounds and the veil lifting with a sub $10 item. :)

I've got two of them. One I bought on amazon for about $10 and one was included with my VPI Scout 1.1.

I do like the one that I got with the VPI better. The weighing surface is closer to where the record height would be, which will give you a more accurate reading.
 
Now now, you've should've plopped out the additional $50 for an audiophile grade scale. You've never get the blacker backgrounds and the veil lifting with a sub $10 item. :)

I've got two of them. One I bought on amazon for about $10 and one was included with my VPI Scout 1.1.

I do like the one that I got with the VPI better. The weighing surface is closer to where the record height would be, which will give you a more accurate reading.

Funny!

Couldn't that be fixed with a block of wood or something? Just asking.
 
I bought one of these and they are great! I also used it to shed 20 pounds! I went straight into the next meal by the time I finished weighting all of the peas and corn kernels.
 
Most of the scales on the counterweight are not overly accurate. They are "calibrated" for some specific weight of cartridge. If what yours weighs is not the same as whatever was used to set that scale up, its going to be off one way or the other. THey're used more as an estimation than anything else. They're usually close enough to get you somewhere within the reccomended tracking force range, but thats about it.
 
The tracking weight isn't determined by the turntable, it's determined by the cartridge/stylus combination. I agree, cheapie digital scales are great and mine is dead accurate when checked with lab calibration weights.

BTW a dollar bill weighs precisely 1 gram

The weighing surface is closer to where the record height would be, which will give you a more accurate reading.

Well sort of ... Test Equipment:

Toshiba SR-F770 DD Turntable w/ Signet TK7EA Cartridge
100 gram x .01 g Mini-CD Stealth Scale
Levolution 12" Spirit Level
Starrett 6" Combination Square (height gauge)
George Shearing, The Shearing Touch LP (Capitol ST-1472)
36 RIAA Equalized Ceramic Poker Chips (blue and white randomized to discourage standing waves and/or 3rd order harmonics)
1 Andrew Jackson Family Portrait for Control

Test Setup:

Cowboy Junkies on the stereo. TT leveled. Arm leveled. Platter removed after 'normal' play height measurement taken using The Shearing Touch LP which seemed a nice smooth, calm choice.



Test Procedure:

In all 50 measurements were taken. 10 for control and 10 at each of 4 heights as per the table below. The arm would not go any lower or another set of measurements would have been captured. The scale was shut off and then powered up to self zero for each measurement. The stylus contact location on the scale remained very close for all measurements. The tracking force was set to 1.25 g for measurement 1 at +0.63 inches. The 0.26 inch above normal measurement corresponds to this scale on this turntable with the rubber matt removed.



In Conclusion:

As the arm was lowered the measured tracking force followed.
The rate of change in measured tracking force seems to be fairly linear.
The deviation of the control measurements exceeded the tracking force measurements.
The maximum deviation for all 40 measurements was 0.11 g. The control deviation was 0.04 g. Therefore the maximum deviation of measured tracking force can reasonably be said to be .5(0.11 - 0.04) = 0.04 g

Opinion:

Until I get an expensive SoundSmith strain gauge or Ortofon SPU cartridge my $15 digital scale should do just fine.
I still don't understand why the measurements follow the arm. Intuition tells me this is backwards. As the angle is increased the pivot would seem to bear more of the force, so the force at the stylus should decrease?

Just For Sh!ts and Giggles:

I took a few measurements at the +0.63 inch elevation with the same 9 chips on the scale. The weight of chips is 76 grams which puts the measurement much closer to midrange for the scale. The control bill still weighed in a 0.98 grams, but the TF consistently measured 1.32 grams or 0.06 g higher than the average at that height.



Still probably negligible.[/QUOTE]

[url]http://www.audiokarma.org/forums/attachment.php?attachmentid=260423&d=1299275930
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Test Equipment:

Toshiba SR-F770 DD Turntable w/ Signet TK7EA Cartridge
100 gram x .01 g Mini-CD Stealth Scale
Levolution 12" Spirit Level
Starrett 6" Combination Square (height gauge)
George Shearing, The Shearing Touch LP (Capitol ST-1472)
36 RIAA Equalized Ceramic Poker Chips (blue and white randomized to discourage standing waves and/or 3rd order harmonics)
1 Andrew Jackson Family Portrait for Control

Test Setup:

Cowboy Junkies on the stereo. TT leveled. Arm leveled. Platter removed after 'normal' play height measurement taken using The Shearing Touch LP which seemed a nice smooth, calm choice.

attachment.php


Test Procedure:

In all 50 measurements were taken. 10 for control and 10 at each of 4 heights as per the table below. The arm would not go any lower or another set of measurements would have been captured. The scale was shut off and then powered up to self zero for each measurement. The stylus contact location on the scale remained very close for all measurements. The tracking force was set to 1.25 g for measurement 1 at +0.63 inches. The 0.26 inch above normal measurement corresponds to this scale on this turntable with the rubber matt removed.

attachment.php


In Conclusion:

As the arm was lowered the measured tracking force followed.
The rate of change in measured tracking force seems to be fairly linear.
The deviation of the control measurements exceeded the tracking force measurements.
The maximum deviation for all 40 measurements was 0.11 g. The control deviation was 0.04 g. Therefore the maximum deviation of measured tracking force can reasonably be said to be .5(0.11 - 0.04) = 0.04 g

Opinion:

Until I get an expensive SoundSmith strain gauge or Ortofon SPU cartridge my $15 digital scale should do just fine.
I still don't understand why the measurements follow the arm. Intuition tells me this is backwards. As the angle is increased the pivot would seem to bear more of the force, so the force at the stylus should decrease?

Just For Sh!ts and Giggles:

I took a few measurements at the +0.63 inch elevation with the same 9 chips on the scale. The weight of chips is 76 grams which puts the measurement much closer to midrange for the scale. The control bill still weighed in a 0.98 grams, but the TF consistently measured 1.32 grams or 0.06 g higher than the average at that height.

attachment.php


Still probably negligible.

http://www.audiokarma.org/forums/attachment.php?attachmentid=260423&d=1299275930[/URL]
 
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