Garrard 401 advice please

[marcusD]

1 hour ago, mr_gray said:

yes Audio Note TT3 is 3 motor belt drive. 

 

ah i was wondering what people "use" when they speak of W&F. 

 

I saw a chap had written "The defacto "wanted to have" Hi-Fi standard back in the day was 0.05% WRMS or better. "  So it seems WRMS or weighted Root Mean Square

 

So for W&F WRMS and RMS for 401 i measured

401 - 0.006/0.02

 

ShaknASpin doesn't say but i presume these might be 0.006% for WRMS?  Seems very low.

 

 

[marcusD]

Wrms is shown on the shaknspin, right next to DIN

[mr_gray]

[marcusD]

15 minutes ago, mr_gray said:

Nice one

your table is measuring great

[marcusD]

For a 401 those are really good measurements 

[mr_gray]

so your measurements are from the commonwealth?  your DIN is an order of magnitude less than mine.  i really like the way the shaknspin identifies the main frequencies at which W and F discrepancies are coming from.  it really is a long way from when a 401 was a noisy table with rumble issues etc. 

 

i have been advised that spindle, mat and possibly new idler wheel are on the way.  due next week.  i can't wait to get the copper mat.  i feel like the Vertere mat is too damping.  the music sounds a little fresh frozen.  not nestled in its harmonic wispiness as it should be.  i think when i get the mat i am going to suddenly hear alot more music and be a bit shocked. 

 

also Marcus when the shaknspin says WRMS is 0.006 is that 0.006% do you think?  Seems odd that everyone talks about WRMS as a % but then shaknspin displays it without units (even though other metrics have the % sign shown). 

[marcusD]

4 hours ago, mr_gray said:

so your measurements are from the commonwealth?  your DIN is an order of magnitude less than mine.  i really like the way the shaknspin identifies the main frequencies at which W and F discrepancies are coming from.  it really is a long way from when a 401 was a noisy table with rumble issues etc. 

 

i have been advised that spindle, mat and possibly new idler wheel are on the way.  due next week.  i can't wait to get the copper mat.  i feel like the Vertere mat is too damping.  the music sounds a little fresh frozen.  not nestled in its harmonic wispiness as it should be.  i think when i get the mat i am going to suddenly hear alot more music and be a bit shocked. 

 

also Marcus when the shaknspin says WRMS is 0.006 is that 0.006% do you think?  Seems odd that everyone talks about WRMS as a % but then shaknspin displays it without units (even though other metrics have the % sign shown). 

Copper mats do make a big difference.

And I presume that WRMS is a percentage because that is how it is expressed.

My 401 can’t match your numbers, my flutter is the same but the WOW is stubborn around 0.06 to 0.08 which of course makes the WRMS higher. Here is my 401

[marcusD]

I am happy with the performance of my 401, It can become a rabbit hole trying to lower your numbers on a turntable, and let’s face it we are dealing with micro improvements with these numbers, and just like motor racing micro improvements can cost mega money and I’m not sure if lowering my wow from 0.08 to 0.02 is actually audible.

I think once you fit the copper mat you will be at the peak of your journey with your 401.

[aussievintage]

3 hours ago, marcusD said:

My 401 can’t match your numbers, my flutter is the same but the WOW is stubborn around 0.06 to 0.08

 

 

My Peak/CEC FR-250 idler is similarly about 0.06.        However, all this looseness with units and lack of them is worrying.  So instead of saying 0.06, I should be saying +/- 0.06%  to 2 sigma,   for example.  This is how an RPM app reports it.  I wonder how, internally, the Shaknspin treats it's data and statistically removes outlying readings?

[marcusD]

16 minutes ago, aussievintage said:

 

 

My Peak/CEC FR-250 idler is similarly about 0.06.        However, all this looseness with units and lack of them is worrying.  So instead of saying 0.06, I should be saying +/- 0.06%  to 2 sigma,   for example.  This is how an RPM app reports it.  I wonder how, internally, the Shaknspin treats it's data and statistically removes outlying readings?

Don’t know sorry,

I don’t trust phone apps for turntables and haven’t used one in years.

you can cycle through the shaknspin displays and get more in depth information if required but I don’t tend to. The wow and flutter readings I presume are 2 sigma but the display doesn’t have room to name everything.

You can however download via Bluetooth from the shaknspin and really bore yourself to death with information.

what do you think is missing from the display?, it gives all the information you need plus some you don’t, it gives you WOW and Flutter, DIN and WRMS, plus all the speed readings.

[marcusD]

User manual Shaknspin v13.pdf

Here you go, this has all the technical stuff as far as what is measured and how.

[mr_gray]

i have connected my shaknspin to phone and downloaded too much data that i will never look at.  one of the cool things about it is that once you make a new measurement or turn it off - the measurement is gone.  it makes it feel less obsessive and somehow aligned with hifi - as in it is what is happening now that counts.  yesterday's system is just that.

 

given that it is a % from the shaknspin and given that 0.05% was once considered a "standard" for excellent - your 401 is still 0.01% WRMS or one fifth of the "excellent" score.  it will be fun to see how:

- spindle

- new idler wheel

- new mat

 

impact the W&F/speed but i agree Marcus unlikely to hear much from any improvement given the very low numbers currently being achieved.

 

it would be interesting to measure W&F for the three tables i assessed but when playing an actual record.  see if stylus drag shows up in the numbers?

[aussievintage]

2 hours ago, marcusD said:

User manual Shaknspin v13.pdf 2.97 MB · 3 downloads

Here you go, this has all the technical stuff as far as what is measured and how.

 

It appears it uses the 2 sigma value of the data it collects as well.  I would suggest that a phone app can be better trusted if the writer of the app knows that they need to do things like this to interpret the data.  That's why some phone apps are better than others.  Also, some hardware is better than others,  so my phone or your phone might be better, even with the same software.

[aussievintage]

1 minute ago, mr_gray said:

it would be interesting to measure W&F for the three tables i assessed but when playing an actual record.  see if stylus drag shows up in the numbers?

 

I always measure it while playing a record as, yes, I believe it can have an effect, particularly on less direct drive methods.

 

That said, none of my tables have enough W&F to effect my listening exprience.  The only problem I get is with off- centre grooves and holes.

[mr_gray]

how do you make the measurements @aussievintage

[marcusD]

36 minutes ago, aussievintage said:

 

I always measure it while playing a record as, yes, I believe it can have an effect, particularly on less direct drive methods.

 

That said, none of my tables have enough W&F to effect my listening exprience.  The only problem I get is with off- centre grooves and holes.

Yes I agree, I build perfect tables for an imperfect medium 

[marcusD]

1 hour ago, mr_gray said:

i have connected my shaknspin to phone and downloaded too much data that i will never look at.  one of the cool things about it is that once you make a new measurement or turn it off - the measurement is gone.  it makes it feel less obsessive and somehow aligned with hifi - as in it is what is happening now that counts.  yesterday's system is just that.

 

given that it is a % from the shaknspin and given that 0.05% was once considered a "standard" for excellent - your 401 is still 0.01% WRMS or one fifth of the "excellent" score.  it will be fun to see how:

- spindle

- new idler wheel

- new mat

 

impact the W&F/speed but i agree Marcus unlikely to hear much from any improvement given the very low numbers currently being achieved.

 

it would be interesting to measure W&F for the three tables i assessed but when playing an actual record.  see if stylus drag shows up in the numbers?

Stylus drag really only affects belt drive in my experience, a couple of grams down pressure from a stylus isn’t going to upset an idler or DD.

you may get slightly wonky figures with a brand new bearing installed, I find bearings normally need at least 50 hours to bed in properly 

[mr_gray]

that is interesting to hear re: stylus drag.  one of the tidbits i have picked up was that a triple motor belt drive, whilst very powerful and torquey, can be in a rather precarious equilibrium.  stylus drag as an input to such a system is of more consequence. apparently.  so yeah i would do it ideally for all 3 tables and see how much change there is from record playing to no record.  this exercise would require me to install a cart on two turntables so it will likely never happen   but in theory it would capture belt drive, idler drive and direct drive so would be better than nothing as an assessment perhaps (likely not).

[aussievintage]

2 hours ago, mr_gray said:

how do you make the measurements @aussievintage

 

I am using a phone app, that, as I was saying, estimates W&F from data that has been processed and within 2 sigma. I like to keep in mind that it is an estimate, as wow & flutter is defined as delta freq / frequency of an audio signal being played back.   Still, repeatable measurements are a good sign.

 

So, I put a record on the table, and a centre weight with a flat top that is high enough to clear the headshell as the record rotates.   I start the record playing,  cued to a passage of good music, and take a reading.  I balance the phone across that flat top to minimise out-of-balance weight effects.  I have tried while playing loud passages vs soft, and don't find much difference, but then it is an idler drive.

Edited June 13, 2024 by aussievintage

[Peterbean]

I am selling mine. It has the very popular pentagram upgrade. Hand constructed in Audiophile quality marker 

[mr_gray]

your Garrard looks like a good place for someone to start @Peterbean

 

they are great tables and as this thread attests quite rewarding to upgrade and very modular in that regard.  do one thing, do twelve things.  you get benefit.  

[cafe latte]

On 13/06/2024 at 1:18 PM, marcusD said:

Stylus drag really only affects belt drive in my experience, a couple of grams down pressure from a stylus isn’t going to upset an idler or DD.

you may get slightly wonky figures with a brand new bearing installed, I find bearings normally need at least 50 hours to bed in properly 

I have seen it affect my Dual 1229, as the stylus lands you actually see thr dots change, so I have set thr speed with the stylus in the groove.

Kuzma did an experiment with a 60kg platter and an air bearing. He unhooked the belt when it got up to speed and it continued to spin for over 30 hours. He repeated the experiment with the stylus down and thr platter stopped on minutes. Different modulations ie music type stops it in different times. 

I have observed this on thr Dual strobe when there is a modulated passage as a small pulse in the strobe.

Commonwealth and 401s have even heavier platters and stronger motors, but it would be an interesting experiment to see how the measurements differ with different types of music playing.

Chris

[Warren Jones]

On 13/06/2024 at 1:18 PM, marcusD said:

Stylus drag really only affects belt drive in my experience, a couple of grams down pressure from a stylus isn’t going to upset an idler or DD.

you may get slightly wonky figures with a brand new bearing installed, I find bearings normally need at least 50 hours to bed in properly 

 

I have measured my SP10mk2 by FM demodulating the FG motor feedback signal. W&F was 0.0107% RMS and playing a highly modulated track 0.0115% RMS both Unweighted.

 

What people do not realise is even inaudible speed variations can have audible effects. Speed variations FM modulate every note. While the actual W&F might not be audible the effect can be. And errors add so any speed variation in the cutting process will be added to TT speed variations.

[Warren Jones]

On 13/06/2024 at 2:02 PM, aussievintage said:

 

I am using a phone app, that, as I was saying, estimates W&F from data that has been processed and within 2 sigma. I like to keep in mind that it is an estimate, as wow & flutter is defined as delta freq / frequency of an audio signal being played back.   Still, repeatable measurements are a good sign.

 

 

2 sigma means only data within 2 standard deviations from the mean is included in the measurement all data outside is discarded. So it's possible for a lot of measurement points to be out of the measurement pool and you would never know. I know 2 sigma is used in calibration labs to report uncertainty in measurement but a person is making the decision on the data scatter.

 

A good example is firing 100 arrows at a target, 95 arrows hit the target and 5 miss completely. Even worse these devices average the measurement so if those 95 arrows hit the edge of the target and backboard but the average can add up to a bullseye.

[aussievintage]

3 hours ago, Warren Jones said:

 

2 sigma means only data within 2 standard deviations from the mean is included in the measurement all data outside is discarded. So it's possible for a lot of measurement points to be out of the measurement pool and you would never know. I know 2 sigma is used in calibration labs to report uncertainty in measurement but a person is making the decision on the data scatter.

 

A good example is firing 100 arrows at a target, 95 arrows hit the target and 5 miss completely. Even worse these devices average the measurement so if those 95 arrows hit the edge of the target and backboard but the average can add up to a bullseye.

 

 

I think you'll find they thought of that.  For example, taking a measurement by just holding the thing in your hand will result in an error that the speed seems to be inconsistent.  As with all measurements, you need to build in sanity checks, and they seem to have done this.  Also, they print a graph of the speed over the 10 second measurement window, so you can manually vet the readings.