Double Pulley Assembly

by **bacobits** » 25 Jun 2011 00:59

Double pulley Assembly on a P5 with the TTPS.

With my parts, and this is important I will state why.
1. GT Reference Sub-platter
2. GT Acrylic Platter

The small gear puller I purchased was not usable because the original Rega Pulley will not fit into it. See pict. Per Michael's direction I carefully used 2 same sized screw drivers, and it worked, go slowly. I used some Acetone on a cotton swab, not soaked, dabbed the top of the old pulley, let it set a few minutes. I also had paper towels around the shaft of the motor to not get any down the shaft. At first the motor must have been disturbed in some way and didn't start. That's when I got upset. Patience required. I did not think this motor was that delicate. It set itself and started up.

Once I got the old pulley off this is the New double pulley assembled. More on this.

The new pulley is very nicely machined. Michael does nice work. It is Stainless steel not aluminum as is on the P5. The new pulley is a a bit long. At the bottom I shaved off on the grinder about a little more than 1/32". This had to be done to keep the belts aligned on the Reference version GT Sub platter. Maybe because of the Delran spacers installed on this Sub-platter. See pict. The belts are very close to the edge even now.
The new pulley had to be shortened a bit to fit lower on the motor shaft to get this close of an alignment or the belts will pop off on rotation.

Now, this might align a bit different on all the different sub-platters out there. So an adjustment might be needed. The worst part I had was getting the old pulley off.

Once fitted this is how it looks and works. I might add that these belts need to be clean because they just kiss the sub-platter assembly. I still push start the platter a bit.

What I thought was going to be an easy 20 minute job it was not.
Was it worth it? Yes, I will have comments in a few days living with this change.

I hope this can help out a bit with others doing this upgrade.

Michael, you are welcome to use any of this on your Blog.

D

by **nabil** » 25 Jun 2011 02:38

Looks Great bacobits... of course the answer we are all waiting for is... how does it sound?

by **bacobits** » 25 Jun 2011 03:26

I was going to wait but these are first impressions I heard immediately.

First noticed pace of songs picked up PRAT and a lot of it. Some of Rega's PRAT might have been lost in the other upgrades, maybe the platter?? It's all back now. Worth the price of that alone.

Piano will show this immediately, I listen to a fair amount of piano. Bob James, Joe Sample, Dave Grusin, Dan Siegel, etc.
One Particular album that is really hard to sound right on a TT Is Bob James, Hands Down. The song is Janus. If the table speed is not correct, wow, flutter, and speed will show on this song. CD sounds fine as does the Turntable now especially with this dual Pulley. Very natural sounding piano. A single white belt did this too but not as much as this. Who knows the double pulley might be machined more accurately, but it is there.

You can hear the PRAT and slam on Herb Alpert's Fandango album. Just excellent!

Things do sound more "human" as someone else stated. Just toe tapping good. Instrument and musician separation is nice. Voice breathy, real sounding. Sade, Diamond Life Album.

So, I think the mod is worth the trouble. I would say that this P5 is close to the P7 now maybe with better parts and machining too. It is not close to the retail of the P7. I see there is a P7 on Agon right now for $1300, now that is pretty good.

I suspect Michael's Motor Isolation system might make this an easier install.

Hey, I'm done for awhile.

D

by **brassnwood** » 25 Jun 2011 17:21

Hi Guys,
An additional view on the ‘double Pulley’ theme for you ….
If you are in the market for a Rega TTPS (or just a new motor) it’s worth considering a look @ the Origin Live DC motor & supply upgrade.
See http://www.turntable-power-supply.com/info.htm
I went for the advanced upgrade (from the retirement fund:-) & found it is easy to fit, speed control is now infinitely adjustable to 33.3 & 45rpm & sounds Great.
I then decided to mod my Rega sub-platter & because the pulley on the new motor can use either a flat belt in the middle [on the crown] or a Rega belt top or bottom groove of the pulley!!! I thought it worth a try to fit Two White belts [one in the top groove & one in the bottom …. Simple:-]
The sound now just ‘Hits the Sweet Spot’

G

by **bacobits** » 25 Jun 2011 18:58

That OL upgrade can be expensive, but no doubt sounds great.
I see, "from the retirement fund:-)" I understand. :crazy:

The problem with some $$ upgrades comes down to how long your going to keep the piece and the need to sell it separate because you will not re-coup the money. My way of thinking, I most of the time buy used.

The description of the sound of this OL motor upgrade is what I am hearing with the double pulley setup almost exactly, to the same extent I would not know without a direct comparison.

It sounds damn GOOD!

D :crazy:

by **watercourse** » 25 Jun 2011 23:26

Thanks for posting your installation tips! This is helpful as I have the exact setup as you.
Out of curiosity: Did you try putting the stock glass platter on with the double pulley setup to see how this sounded in comparison? Also, are you able to check the speed accuracy after the mod?
I also assume that you can't reinstall the stock pulley after the mod?
Thanks Den!

by **diviy** » 26 Jun 2011 01:01

My pulley just popped off under finger pressure and I can refit mine if I wanted to.

by **bacobits** » 26 Jun 2011 21:07

As diviy says you can re-install the old Pulley again with a bit of super glue.

Wilson, no I didn't try the glass platter on the double pulley I will get to it since you brought to up. Also no, on the question of speed accuracy I don't have a strobe here, just my piano music used and it shows there.

The double pulley without me measuring speed accuracy gives the music flow and it sounds more refined in the tempo especially. On music as on Steve Miller Band a lot of background rhythm comes forward and detailed.
Pretty cool. A bit more slam on crescendos. A more natural soundstage front to back, width stays about the same here. Amazing just an extra belt can do that. Although, if you read the description and the science of changing the motor on Origin Live's site I guess it's not that surprising. Interesting reading. I wonder how that motor change would sound with the double pulley?

If you take the stock motor assembly apart as I did, there are further adjustments you can make. Like isolating the 2 hold down screws from under a bit better with thicker washers, or even lowering the motor a bit to align the pulley better. I just shaved off the little more than the 1/16 in length on the pulley as a quicker fix. Michael Lim offers a completely isolated system from the plinth for the stock motor. At a reasonable cost.
Someone here has it but has not made any comments or supplied picts yet.

It comes down to how far you want to take the $$ on this table and how long your going to keep it. If you buy used at a great price that is the way to go.

For the $45 +$36 belt invested in this particular upgrade I would say it is well worth the minor trouble if you run into any. Most here have not and it works.

Patience! Any questions just holler.

D

by **watercourse** » 26 Jun 2011 22:29

I have been emailing Michael Lim about removing some material from the double pulley. He suggested that I use some washers to increase the standoff distance between the motor and the plinth. Sounds like a very simple solution. Heck, I could even use some vibration-isolating materials instead of just metal washers to increase the standoff. Any thoughts on that?
Also, looking about the double pulley setup, I can't help but think that this is a very good approach given the additional mass that the single belt has to deal with going from the resin subplatter to the aluminum as we have when using the GT subplatter. If the idea too was that the belts are supposed to partly absorb motor vibrations, then two belts would work that much better as well.
I think you've helped me make my decision, D. Now wish me luck!
PS Re: OL motor change - for the price, you can get a lot of LPs right there. Has anyone been able to compare the OL mid-level motor upgrade to the Rega TTPSU? Probably a tall order...
Wilson

by **brassnwood** » 27 Jun 2011 03:02

Yes Wilson, use vibration-isolating materials between motor & plinth – at the same time do not fully tighten the screws down – Music sounds sweeter if it’s not clamped down tight; Try it  (same thing is applicable on the old RB250/300 arms when tightening the large base nut to the plinth …. again, try it.
Completely Isolating the motor as per Michael Lim suggestion is definitely the way to go when the funds build up again – also check out http://srm-tech.co.uk/shop/article_RSB1 ... %3DRSB1%26 for isolating base & motor de-couple comparison.
‘D’ I wonder how that OL motor change would sound with the double pulley?
The OL motor change has got a version of the double pulley as I mentioned earlier. It improves the music right across the board! ie. Bass/soundstage/depth – backing vocals can be clearly heard now where previously they were less audible.
I’ve never had the Rega TTPSU Wilson, so I cannot compare with my OL set-up. I guess the main difference is that the OL is a DC motor as opposed to the AC Rega type & as you say that theory is explained on the OL website.
Cheers,
G

by **gabriel1998** » 30 Jun 2011 07:59

bacobits wrote:I was going to wait but these are first impressions I heard immediately.

First noticed pace of songs picked up PRAT and a lot of it. Some of Rega's PRAT might have been lost in the other upgrades, maybe the platter?? It's all back now. Worth the price of that alone.

Piano will show this immediately, I listen to a fair amount of piano. Bob James, Joe Sample, Dave Grusin, Dan Siegel, etc.
One Particular album that is really hard to sound right on a TT Is Bob James, Hands Down. The song is Janus. If the table speed is not correct, wow, flutter, and speed will show on this song. CD sounds fine as does the Turntable now especially with this dual Pulley. Very natural sounding piano. A single white belt did this too but not as much as this. Who knows the double pulley might be machined more accurately, but it is there.

You can hear the PRAT and slam on Herb Alpert's Fandango album. Just excellent!

Things do sound more "human" as someone else stated. Just toe tapping good. Instrument and musician separation is nice. Voice breathy, real sounding. Sade, Diamond Life Album.

So, I think the mod is worth the trouble. I would say that this P5 is close to the P7 now maybe with better parts and machining too. It is not close to the retail of the P7. I see there is a P7 on Agon right now for $1300, now that is pretty good.

I suspect Michael's Motor Isolation system might make this an easier install.

Hey, I'm done for awhile.

D

it looks like you are cutting it close with the top belt..Finally got mine. I had to shave some off to fit my P25:

The noise floor is non-existent..WOW

by **bacobits** » 30 Jun 2011 08:34

That looks good. I'll have to trim mine a little bit more.

D

by **gabriel1998** » 05 Jul 2011 14:39

bacobits wrote:That looks good. I'll have to trim mine a little bit more.

D

I think its pretty shitty that after all that. You still have to shave or cut it to get it to fit. For P25 Owners this "WILL NOT" fit unless you cut it almost all the way to the allen key slot and its quite a bit. better invest in a dremel.

by **bacobits** » 05 Jul 2011 15:24

Aww it's not that bad. I think it's shitty of Rega using wood screws on the tonearm 3 point mounting and no set screw on the pulley. Hell, why do some of the Rega's have plastic pulleys anyway?

There are too many different sub-platters out there. Michael also makes one. If you look at the GT offerings the difference of the Reference and Deluxe models are the Delrin tabs. The Deluxe model has about 1/16 tabs machined in to raise the platter. Is this hub a bit thicker to keep the original VTA height for the platter? I didn't check it when I had one here but more than likely it is or higher on the spindle to adjust. SO I would say on all the Sub-platters there could be at least 3/32" adjustment necessary on that Pulley. That is about the total I took mine down.

After adjusting mine shorter and reinstalling I noticed a tick noise from the motor. The Pulley was too low on the motor shaft. I took it up a bit and it is perfectly silent now.

Also, the left motor attaching screw is slotted for belt adjustment I presume. The belts are adjusted to just kiss that sub-platter and not stretch at all. If you see a stretch on the belts when installing the Pulley they may be too tight and the motor should be pushed in a little. This adjustment was this way before I took the motor all apart. Also don't tighten too much either of the screws. Just enough to lock the motor in place. It does sound better.

Some posters here have ordered Michael's motor Isolation piece. I'm interested in how it looks in set up and how it sounds.

Sorry for being long winded, but if your doing this pulley set up on a P5 especially, you should know what you're up against.

But, it sounds damn good!!!!

Den