LP12

[Lordie82360now]

Even though I have no desire to get back into vinyl and therefore own a record deck I do find the reports of associated trials and tribulations so interesting!
Back in the day I so enjoyed tweaking, modding and resetting firstly a Goldring 78, then a Fons CQ30 and latterly a Heybrook TT2. Nothing major as you guys are doing, but enough to drive my wife around the bend!
I suppose it was the detail and continually adding and taking away bits, new arms, cartridges and head shells.
I am sure you guys are equally meticulous about your vinyl - I was always taking back warped copies of albums to my local independent shop.” That Smell ”by Lynyrd Skynyrd was an absolute pig I remember!
I must have also shown some austistic tendencies cataloguing my collection also meticulously (along with self recorded cassettes printing titles and artists on the box spines with a Rotring pen and stencil) and spending a fortune on Nagoaka inner sleeves.
Keep up the good work and more power to your elbow!

[karatestu]

Why does my turntable produce a more full bass presentation than my cdp? Is it just what vinyl does or do I have a feedback problem?

[karatestu]

Touch a bit of wire to the arm tube and to the phono ground point, that might shut it up. the aro has a jewel bearing so has 2 internal ground wires, one from the tube and one from the pillar because the bearinf doesnt conduct. if the tube one is dodgy you can get loud hum.

The crack when switching a light on probably means the phono is picking up a spike from the switch in the lamp because there is no cap on it

I just realised the outer coating of the aro arm tube is not conductive by not getting any continuity with a dmm . I will have to find a spot that has no coating so I can do the wire thing you suggested again.

So it still could be that after all.

[antonio66]

Goodbye Linn Lingo hello Avondale Audio Taps2 psu

I just released the four ac motor wires from the lingo pcb attached to the crossbrace, commoned the two grey wires and put them into a choc block. Cable from the taps psu has same wiring colours so couldn't go wrong although if I had red and blue reversed then the platter would rotate backwards.

Inside. It a dinky little thing. Uses two EI frame transformers and is similar in principle to the geddon but a bit more sophisticated.



Straight off I much prefer this psu to the lingo.

[karatestu]

Today's surgery involves an EI transformer, Avondale minicap module (4 rectifier diodes+ 6 smoothing capacitors) , 1 metre of three core mains flex and a phono1.

Transformer is a bit bigger than the toroid in the phono1. It came out of a broken active studio monitor and is shielded. Minicap module has three 2,200uv caps in parallel for each part of the split power rail ( positive and negative). They were originally for the front end of my diy Avondale Voyager power amps. Theg do have low value inductor between each cap but they will probably get removed and a wire link inserted.

The metre of main flex will connect to that and be connected at the other end to the phono1. Idea is to get the psu and it's noisy charging circuit current loop (transformer > rectifier > cap bank > transformer) well away from the delicate amplifier board.

If I lift the two solid tinned wires on the rectifier with a soldering iron I will then be able to bend the end away and connect my pos and neg wires there, 0V wire will connect between the existing pair of caps in the phono1. That way I get to utilise the last pair of caps, keep some caps close to the load and use the resistance of the one metre of flex as part of a noise eating CRC filter. So that will make what people would call a CLCLCRC arrangement- cap, inductor, cap, inductor, cap, resistor, cap . Inductors may get removed but I can't do anything about the resistance of the wire - it should be relatively small.

What will this do for what enters my lug holes ? Who knows. The CLCLC smoothing filters were/ are popular with the group who build Avondale stuff or bodge Naim . Some claim to be able to hear when the inductors are in circuit and a minority don't like it. Can't say I have done a comparison but I do have more of these cap banks that I could remove the inductors from and do a quick (ish) swap over. Might be getting into some obsessive compulsive territory here though

This will just be for experimenting of course and as only two wires get lifted in the phoho1, it can go back to stock easy enough (nothing is removed).

[karatestu]

Power supply is built (on a sheet of chipboard obviously ) and tested.



Outputs 31V. Original psu gives 29V under load whilst playing a record. Amp boards run at +/- 20V so a bit more voltage to drop. Regulators are not heatsinked but 2V more at this low current draw shouldn't be a problem.

The two wires going to the bridge rectifier in the phono1 are removed and bent up. New wiring soldered in and original transformer and rectifier are isolated .



Just need to connect the psu and phono1 and bring up to full voltage with my variac. Then plumb the bugger in and listen.

[Geoff.R.G]

Turntables, need to stabilise before playing a record in the same way that an oven needs to stabilise before cooking, I believe three cycles are the recommended warm-up. The stabilisation time for a turntable will obviously depend on the mass and radius of gyration of the platter.

The stabilisation time for my EMT 950 is 0.2 seconds. Thanks to the Hall Effect direct drive motor and feedback system. It has a relatively low mass platter, because that's what EMT found sounded best.

Hardly your average domestic turntable though is it?

[Geoff.R.G]

Stu, please excuse my confusion but is the new PSU intended for the LP12 or some other project, I am confused.

[karatestu]

Stu, please excuse my confusion but is the new PSU intended for the LP12 or some other project, I am confused.

Oh sorry Geoff.

It's for the nva phono stage. Disabled the original transformer and rectifier and added this remote one.

It's to see if any of the hum I am getting is due to the original transformer being close to the amplifier board. Has the added benefit of assessing what a remote psu can do for SQ.

Loosely related to the LP12

[karatestu]

New, remote PSU is in and hum has gone . It sounds a load better too

I have another of those EI transformers and minicap modules so I can see a twin psu in my future.