Cartridges height

[scott_01]

I assume this is a modified SL12xxx? That 24 volts goes directly to an IC which contains drivers and to a subsidiary regulator that produces 9v for the clocks and stuff. I think it's not comparable to what goes on in a Lingo or the SME PSU. That's handled by the IC. Do any of the SL1200 modders dig right into that area?


If you include all the electronics then it's a 'brush less DC motor'. But the DC is very isolated from the motor coils which have AC sinusoids passing through them.

Sorry I was talking total rubbish* about the 24v. My TT is an SP10MKII.

The SP10MKII PS only outputs DC at the above voltages so where does the AC come in to play? Is there AC regeneration in the electronics inside the TT unit itself?

Why do they describe the SL1200 motor as DC when in fact it is ac?

I suspect the bulk of the benefit from an external supply for an SL1200 is in the physical removal of the transformer and its associated fields and vibrations.

Yes, I'd fully agree with that. I think from a wow / flutter POV that the external nature of the PS makes no difference. I suppose the point I was trying to make was that decent not to say improved PS are widely accepted as bringing audible benefits.

Good luck with the SP10, mine's in the Obsidian plinth and I'm loath to change it.

*No jokes about the rest of my post(s)

 

[Paul Ranson]

Is there AC regeneration in the electronics inside the TT unit itself?

Effectively.

There is no such thing as a DC motor when you look at the currents flowing through the coils. The magnetic fields have to move, DC fields don't move. A simple electric motor has a commutator which switches the power to the coils as the motor turns. Each coil is connected up one way, and then the other. The coil sees AC. But you can run it from a battery and no electronics are involved. This, to me, is a DC motor. More volts, more speed. Replace the commutator with electronic switches, possibly in a brushless arrangement and you get the same effect.

The Technics DD motors sort of fit the latter, but the driver arrangement generates sinusoids rather than square waves, and they could be connected to a 3 phase AC supply and rotate in lock step with the AC frequency.

I suppose the point I was trying to make was that decent not to say improved PS are widely accepted as bringing audible benefits.

It's worth, IMO, being cynical about aftermarket PSU claims. I think in many cases to get a good benefit very invasive modification is required. Linn LP12s are an exception...

Good luck with the SP10, mine's in the Obsidian plinth and I'm loath to change it.

Thanks. Not sure where I'm going with it yet but I think a tangential tone arm will figure in the first iteration.

Paul

 

[Arlequen]

So I wonder if you have to re-evaluate your setup?

Yes Paul! .. I need to change arm or to resize the arm board of the TW Acustic Raven One .. to be able to mount a cartridge less than 18.5mm. tall...
I'm discussing this matter with Thomas (TW Acustic owner and designer)

 

[Markus S]

If I hadn't impulse bought an SP10

You, an impulse buyer? I don't believe it.

 

[Paul Ranson]

I need to change arm or to resize the arm board of the TW Acustic Raven One .. to be able to mount a cartridge less than 18.5mm. tall.

I've had a look at most of the cartridges in the house. All the moving coils are about 16mm. That's an AT33PTG, Supex SD900 and a Linn Arkiv. The MMs are all nearer 20mm. Goldring 10-40, Linn K18 and an old A&R C77.

Paul

 

[scott_01]

Effectively.

There is no such thing as a DC motor when you look at the currents flowing through the coils. The magnetic fields have to move, DC fields don't move. A simple electric motor has a commutator which switches the power to the coils as the motor turns. Each coil is connected up one way, and then the other. The coil sees AC. But you can run it from a battery and no electronics are involved. This, to me, is a DC motor. More volts, more speed. Replace the commutator with electronic switches, possibly in a brushless arrangement and you get the same effect.

The Technics DD motors sort of fit the latter, but the driver arrangement generates sinusoids rather than square waves, and they could be connected to a 3 phase AC supply and rotate in lock step with the AC frequency.

Now I understand, thanks.