Building high-end 'tables cheap at Home Despot II

Mounted new RB300 w/ Denon 103R. Need advise, please.
Did some tweaking with new armboards. New armboard is approx. 2-3mm below top plate. ***Where is yours?

I played an LP

1. seems fast. Timed it and it is about 33rpms in 56 seconds. However, on this table (Lenco 75/S) the slowest adjustment is 33 and I cannot slow it down. Other table goes down to 16 allowing for adjustment.

2. in the middle of the LP, the stylus skipped, not advancing. I lifted and advanced, the stylus would not drop onto grooves. Could be my armboard is too high (thick)*** I placed another mat on top of the first and LP played all the way through. However, #1 and 3 still a problem.

3. Lots of sibilance, i.e. thick and smothered sounding "s" sounds. Could this be related to new Creek phono stage not broken in. Or cart adjustment?

Digital scale reads 1.6 g tracking force.
Not sure about VTA and cart alignment, just eyeballed.

Any ideas?
Thanks from Oreegunn

Problem # 2 may be that your lift mechanism is interfering with the tonearm. Check to see if the flat part that supports your arm is not bent upward. I am not sure if this is the case for number 1 but the notches that set the speeds i.e the 33 45 78 and 16 on mine can be shifted slightly by loosening the screws that hold them in place.
Harry

Hi Michael, if you can't adjust the speed properly at the brackets, then you need to go further into the machine and adjust at the joint which shifts the idler-wheel assembly. This is the circular bit with two screws which pivots around a nut and bolt arrangement: loosen the screws, and move the idler sled backward or forward (with the two screws sliding and changing position on the two arcs) until you get a good range of + or -33 1/3 with the bracket in the middle, then tighten again.

As to the tonearm, does sound like an arm-lift problem as Harry said. Even though the Denon is burning in, and probably the phono stage too, it shouldn't sound so bad. Remember: the tonearm should be parallel to the record with the stylus in the groove. Once this is done, then use the nifty dynamic VTF arrangement on the Rega to increase mass to suit the low-compliance Denon: shift the counterweight as far back as is conmfortable on the end-stub, and then use the spring to achieve 2.5 grams tracking force. Can't do that with an RB-250! I LOVE those RB-300s, especially with MCs (here they stand up to the best, their biggest problem being they're too cheap, and too ubiquitous). However, with Grados I do believe the RB-250 sounds better, but will know more in the future.

09-06-06: Fishwinker
I've got the speed sorted now (thanks 4yanx) - I'd connected the speed lever control to the idler control arm at a very different point on the slide plate to that which it had originally been fixed. Obvious really - feel rather foolish now!
Still can't get rid of the vibration (it's not a bent cone/rotor as far as I can see), but it seems to have reduced slightly over the last couple of days. Maybe it'll bed itself in and sort itself out, but I'm not sure.

Hi Fishwinker,

What is vibrating? The motor, or the idler itself?

-mosin

Hi Mosin,

It was the motor itself vibrating. I tried everything to sort it out, right down to re-centring the coils, but I just could not nail it. Gave up in the end, and got myself another motor which I was able to make a LOT quieter.

Philip