Why is the last track of a side not play as sonically sweet as the tracks before ?

[RobbieGong]

As per thread title. Why is this ? Is this inner groove distortion I've heard you guys mention ? What causes It ? Is it another one of those things in hifi where despite meticulous set up, everything's a compromise ? :scratch:

[Rare Bird]

As in records? probably your anti-skate isnt optimum!

[DSJR]

The "playing speed" is slower and the groove spiral wound more tightly at end of side. The main thing is that high frequencies occupy far less groove-space as at the beginning of side. Conical tips tend to be made to ride higher on high frequencies and this brings about less output. Fine-line style tips trace these inner grooves more accurately, but ride deeper in the groove and can collect debris and reproduce noise more if you're unfortunate.

Obviously, setup for side end tracking error is essential, although it's said that going bananas for correct geometry at beginning of side is less critical. Modern setup gives 65mm from side centre whreas in past decades, 60mm was the preferred. Shorter arms as on old garrard SP25's used 70mm as the null point..

I was told that some pressings had progressive high-treble boost added as the side went on, but I don't know specifics here. My mid 70's copy of Sgt Pepper sounded all but identical to the first CD issue at the beginning of the sides, but the roll-off at side end was clearly audible using a good elliptical stylus (I forget the cartridge, but it would have been a Linn MC one at the time).

[NRG]

Groove velocity is slower at the end of the record vs the outer tracks meaning high frequency information has less room to deflect the stylus. Along with the use of a pivoted tone arm with its angular error, stylus profile and inadequate anti-skate cause end of side distortion.

[Barry]

The "playing speed" is slower and the groove spiral wound more tightly at end of side. The main thing is that high frequencies occupy far less groove-space as at the beginning of side. Conical tips tend to be made to ride higher on high frequencies and this brings about less output. Fine-line style tips trace these inner grooves more accurately, but ride deeper in the groove and can collect debris and reproduce noise more if you're unfortunate.

Obviously, setup for side end tracking error is essential, although it's said that going bananas for correct geometry at beginning of side is less critical. Modern setup gives 65mm from side centre whereas in past decades, 60mm was the preferred. Shorter arms as on old Garrard SP25's used 70mm as the null point.

I was told that some pressings had progressive high-treble boost added as the side went on, but I don't know specifics here. My mid 70's copy of Sgt Pepper sounded all but identical to the first CD issue at the beginning of the sides, but the roll-off at side end was clearly audible using a good elliptical stylus (I forget the cartridge, but it would have been a Linn MC one at the time).

It depends on the geometry employed by the arm designer. If the arm is designed to follow Sevenson's prescription, the radial null-points are at 60 and 117mm. if the arm is designed to follow Bearwald's prescription, the null-points are at 66 and 121mm.

Early UK arms: the Decca and Keith Monks (aka Audio & Design) as well as early SMEs all followed Stevenson. Later SME arms had their geometry changed so as to follow the Baerwald prescription.

[Haselsh1]

I think the 'laws of physics' have a lot to do with it actually

[Johnnie7]

what turntable and arm and cartridge are you using Robbie?

[RobbieGong]

what turntable and arm and cartridge are you using Robbie?

This one Johnnie http://theartofsound.net/forum/showthread.php?t=22629 1210 with Micro Seiki MA 202 & Ortofon 2M Black.

[nat8808]

Groove velocity is slower at the end of the record vs the outer tracks meaning high frequency information has less room to deflect the stylus. Along with the use of a pivoted tone arm with its angular error, stylus profile and inadequate anti-skate cause end of side distortion.

I'd go with this reason..

The physics of a stylus reading a circular groove from the end of a pivoted arm.

out of interest, in theory should the sonic imaging change as you move into the centre? I would have thought the differences between left and right groove walls would be have diverging properties as you move to the centre groove, larger difference in wall length?

[Johnnie7]

This one Johnnie http://theartofsound.net/forum/showthread.php?t=22629 1210 with Micro Seiki MA 202 & Ortofon 2M Black.

deck looks good and cartridge in about the correct position...and its a well made cartridge

keep the stylis clean and this should help any tracking issues

[RobbieGong]

deck looks good and cartridge in about the correct position...and its a well made cartridge

keep the stylis clean and this should help any tracking issues

Cheers Johnnie, I'm pretty meticulous to be honest although I have noticed after getting up really really close that the slight skew I applied to the cartridge in the headshell as part of the whole following arc and sitting perfectly parralllel in at the null point, might be a tad exagerated so I'll look to address :)

[f1eng]

Others have pointed out various parts of it.
There are fundamental limits to the compromises chosen when defining the 33 rpm LP disc standard (which was in its time the analogue equivalent of MP3 in a way, a cheap solution to get more time onto a disc).
Because the rotational speed is constant the linear speed reduces from the outside to the inside of the disc, so the inner part of the record is lower-fi than the outer. All pivoting arms introduce distortion which varies from beginning to end of the disc, being instantaneously zero at two positions on the disc. It depends on the alignment standard chosen but tends to be at its worst at the beginning and end of the disc side.
Parallel tracking arms address the second part of the problem, though most introduce other compromises, the first shortcoming is inherent in all grooved records.

[AlfaGTV]

Just doing some quick calcs:
Groove speed on the first track:
Circumference ~ 88cm ~ 1.8sec/rotation(@33.3rpm) ~ 48cm/sec

Groove speed on the last track:
Circumference ~ 38cm ~ 1.8sec/rotation(@33.3rpm) ~ 21cm/sec

Even not taking into account angle errors this says a lot...
Hope i did my math correct! ;)

Regards / Mike