The product arrived really quickly thanks to FedEx. It arrived properly packed, a cardboard box contained a two-piece plastic foam shell that encased a nice cloth pouch where the pieces were inside.
My goal was to replace the stock Rega RB220 counterweight which is this one:
I understand the RB251 and RB250 uses the same counterweight setup so the upgrade apllies here.
This stock counterweight is clearly a cost reduction affair. It not rigidly attached to the stub, it will resonate or vibrate due to being held in position by just a spring-loaded pin. So here it is something that needs upgrade. Otherwise, I happen to like the RB220 tonearm (as fit on the latest Planar 2), it doesn't have the VTF adjustment spring which is believed by some to be detrminental to the sound.
The TNG-Spinner counterweight, as we will see, will add easy VTF adjustment to the RB220 tonearm and similar.
Also, the TNG-Spinner counterweight can be fit directly to RB303, RB330 and similar tonearms, as well (i will provide pics too).
So the first thing we do is to upgrade the rear stub, from a plastic Rega part to the TNGSpinner metal stub. A closeup shows the difference in quality:
Upgraded rear stub:
The rear stub is of excellent quality and finish.
Doing this
would already be a significant upgrade, since it allows a RP1 counterweight to fit on it, thus mimicking the arrangement on the RB303/330 tonearms.
But we won't stop here, we'll gonna use the TNG-Spinner counterweight.
The counterweight assembly has three parts:
A. The counterweight itself. Available in three weight versions, here i'm choosing the heavier one. It can be augmented in weight by 1,2,or 3 outriggers, each one 10g in weight, allowing a nominal mass range of 110 to 140g. These outriggers just screw in. More on mass later.
B. The main cylinder, it supports the counterweight and mates with the rear stub. Here an internal rubber compliance gives some decoupling. This is a firm compliance, not floppy. Here is the main difference versus the Michell and Iceni counterweights: this is a decoupled design, as are the original Rega counterweights on all their turntables, up to the top P10 or Naia.
C. Counterweight retainer ring (see red arrows below). It fixes the counterweight in position. This is what enables lateral balance adjusment (see later).
Installing the counterweight is just a simple matter of plugging it into the tonearm stub fully. However it is advised to lubricate the inside of the main cylinder (B) with a lubricant (Gus advised WD40) to make VTF adjustment easy. I confirmed that this was the case; it is a good idea.
I also recommend lubricating the counterweight thread so it centers itself easily while you slide the main cylinder (B).
The picture below shows the counterweight on the stub. The correct installation would be to push it fully (it is not fully pushed in on this picture).
By the way, the counterweight fits directly on a RB303/330/similar tonearms, as mentioned above. Here it is on my RB303
(not inserted fully all the way in yet, but you get the idea)
Once fit, it provides something that the stock counterweight (and most other counterweights) do not provide:
lateral balance. You can skew (offset) the counterweight position so you compensate for lateral balance. Then you use the retainer ring (C) to keep the counterweight in the desired position.
Lateral balance allows the tonearm bearings to receive equal pressure, this increases sensitivity.
And, in this case similar to the other alternatives, it is an
underslung counterweight that, thus, places the mass near the same plane as the stylus tip, just as in the SME 3009/III, SME IV, SME V, SME 309 and other great tonearms.
Fine VTF adjustment is possible by simply freeing the retainer ring (C) and then rotating (B), it allows adding or reducing VTF easily, if a bit slowly. If you are compensating for lateral balance, you will need to adjust lateral balance again after the VTF adjustment. If so, recheck the VTF afterwards.
The VTF adjustment itself is already an ergonomic upgrade. On the RB303/330 it also allows easier zero-in (balancing) of the tonearm before applying the regular VTF control dial.
As in any underslung counterweight, if you are using a VTF gauge make sure to measure VTF with the needle positioned at a height that is close to playing height. But you probably know that already.
tng-spinner.com
