Rega RP3 and VTA

I have seen quite a few posts on here-both good and bad--regarding certain cartridge combinations and the problem of no VTA on Rega tables. In my case, I am using an Ortofon 2M Bronze on my RP3. My question does regard proper VTA in a case where it is perfect on 180-gram or 200-gram vinyl, but just a hair off on the 150 gram (normal) LP's. Which should one adjust for? What you have more of? Also, does anyone know of a list of cartridges that do demonstrate proper VTA with Rega tables?
I should add that azimuth is spot on as are both points on a Hudson Protractor.
Thanks.

 

Rega wool mat is 2mm thick. Set it for 180g records. Then if you are insistent to be correct for thinner records, get a 3mm mat for those.

 

Hadn't thought about switching mats. I am currently using Herbies Way Excellent II which is 2mm. I would say getting the same mat in a 2.4 mm thickness to use with the 150gram LP's would do the trick. Judging from the gauge on the Hudson device it is literally about half a millimeter off.

 

I just picked up a Planar 3 and had the dealer install a Nagaoka MP200 on it... I asked if they would need to add spacers and they did not usually add them with the Nagaoka cartridges... now by eye... I would said the arm looks a little high on the cartridge side and so I might look into a spacer myself but the sound as is right now without the spacer is awesome... so I am in no rush to experiment... I will likely try without the mat at all so to see if I hear any difference before I mess with it... like they say, don’t fix what ain’t broke!

 

That's kinda the weakness of Rega turntables, they're not easy to customize. Rega definitely wants you to buy their cartridges and use it on their turntables. If I were you I wouldn't worry too much about it. Will it make a difference? Well... yes. But I'd say have the SRA set to 92 degrees with a record that you'd say is the most common weight that you own in your collection. If you want to obsess over SRA I definitely won't say it's a bad idea but if I were you I'd just find a middle ground and use the time you would use up switching mats to listen to more music. If however you decide to pursue absolute perfection, that mat thickness idea sounds pretty good and will certainly be the easiest method.

 

I have not posted on these forums before but have learned almost everything I know about this hobby from you all here. Thank you!

As vinylontubes suggests, I also think you can adjust for both types of records using a slightly thicker wool mat for thinner records. I have experimented with different mat materials (details below) and found that 100% wool works best with the Rega P3 (2016). I'm not sure if this is a commonly available material in fabric stores, but I purchased some 2.5 mm thick 100% wool felt from an online store called Weir Crafts, which sells 18"x18"sheets in a variety of colors (see link). The 2.5mm thickness is just enough of a bump up from the 2mm Rega felt mat to achieve ideal VTA for thinner records. I received my order yesterday and am very pleased with the sonic results. The material is very similar to the Rega wool mat. It comes in a rectangular sheet. You can trace the circumference and the spindle hole of your Rega mat and cut it out. It needs to be ironed as it comes folded. They say to iron on the "wool" setting or on medium high, an instruction slip is included. I ironed it under a thin cotton cloth and the crease came out nicely. Wool can be ruined by over-ironing so be cautious. Best of all this is the least expensive platter mat option I have found and worth a try for $7 plus shipping.

100% Wool Felt from National Nonwovens | Weir Crafts

If you are interested in how I arrived at this solution here is some background.

I have been experimenting with VTA on my Rega P3 (2016) with Ortofon 2m Blue for years. After adding dual SVS PB-1000 subs and putting in new crossovers on my Paradigm Monitor 7 floor standing speakers, I have settled on using 3.5mm shim from Acoustic Signature. I had previously been using 2.5 mm shim but adding the dual subs and calibrating them using digital recordings with Schiit Bifrost Multibit, I found 2.5mm to be too bass heavy. This also aligns with what Ortofon told me in an email, that VTA should be between 3.2 and 4mm for a 2m Blue.

The problem then became adjusting for the difference between 180 and 200 gram records and the older 120 or 150 gram records, which I have learned are about 0.7 to 1.0 mm different in thickness. I find the thinner records sound a bit bright and lacking in bass impact/detail when VTA is optimized for thicker records. I began experimenting with different ways to raise the Rega wool mat for thinner records using thin sheets of canvass from reusable shopping bags. I also tried layering the Pro-Ject felt mat that measures 1mm underneath and on top of the Rega wool mat figuring that would approximately account for the different in record thickness. Both of these had undesirable results on the sound. I tried a 3mm felt mat from Amazon and a 1.6 mm felt mat by Turntable Lab, also on Amazon. These also negatively impacted the sound. I also tried the Origin Live Platter Mat, and did not care for it's affect on the sound. In my experience the Rega P3 performs best with 100% wool felt.

 

I'm curious what you used to cut the wool...?

 

Half a mm is not going to be audible. As you notice, records vary this much by their own and adjusting VTA for each record, even with "VTA on the fly" adjusters is ludicrous IMO. My advice is to find the sweet spot for whatever record you prefer (whatever you collect the most of) and leave it alone. The advice of using different thickness mats or a shim of paper under the mat is a good one and is easier than any other mechanical adjustment method. In that case, if you even want to fool with that, then you would set the VTA to the tallest record,200g, and then shim any thinner records by swapping mats of placing the sub-mat under your main mat. These mats are easily stored with your records in normal record jackets. But I really can't be bothered with all that myself. I fix the adjustment for the cartridge to standard record height (usually a 2mm spacer on a Rega deck) no matter what table I work with. Then I just play all records on that. The actual SRA isn't effected that much with just a 1mm or even a 2mm change in height at the arm base. I set up my Denon DP-72L table this way and played several records in a row last night on it. They were all different heights and they all sounded great. The tonearm height adjustment is via a set screw or two and no way am I screwing with that every time I want to spin a record.
-Bill

 

It seems much ado about nothing imo! MM here or there? Life's too short, I'm grabbing another record!

 

I just used scissors. Not the most perfect cutting job but close enough for this purpose. The only concern would be to make sure the wool mat is not extending beyond the edge of the record as the cartridge could get caught on the mat.

 

I wanted to give an update on my continued experimenting with different 100% wool mats as a way to adjust VTA between different record thicknesses. I have found another solution that I prefer to the 2.5 mm mat mentioned above. After more listening on the 2.5 mm mat I noticed that thinner records played on this mat, while providing excellent detail and impact of bass and snare drum hits, had rolled off high frequencies. I suspect that the VTA achieved by the 2.5 mm mat was not necessarily the problem, but rather the slightly thicker layer of wool absorbing more high frequencies. Just a guess based on what I heard, I’m ignorant of the physics.

I ended up trying the one other wool felt option from Weir Crafts made of 1.2 mm thick 100% Merino wool. 100% Wool Craft Felt in 60 Vibrant colors! | Weir Crafts
This is thin enough that I don’t think it has to be ironed. I just put a stack of junk records on top of it for an hour or so to flatten it out.

I dropped the arm down from using a 3.5 mm shim to a 3 mm shim and used the 1.2 mm mat for the thick records and the 2mm Rega factory mat for the thinner records. This gives thick records an effective VTA shim of 3.8mm and thin records, 3.0mm. This is sounding great so far and I am even wondering whether this thinner layer of wool may actually improve upon the 2mm Rega stock mat for playback of thicker records, as long as arm height is lowered accordingly.

This is an inexpensive and easy experiment to try if you are looking for VTA adjustment between different record thicknesses.

 

Here is an update in my search for VTA adjustment using different mats. I have decided that the 1.2 mm mat for thicker records, while a step in the right direction, resulted in increased bass boominess, though did preserve the high frequencies well. My current solution that seems to be another step in the direction of improvement is to use the 1.2 mm mat from Weir Crafts with a thin layer cut from a merino wool sweater like this one. This is very thin material, not what you would typically think of as a sweater. It's basically a wool shirt. $10 at Goodwill. I assume cashmere would work just as well.
ll bean merino wool turtleneck argyle - Google Search

I recommend cutting the circle a bit larger than the turntable platter because the ends tend to curl under itself because the material is thin. This is easy to flatten out, but a bit of a hassle. This material is difficult to cut into a circular shape and does not produce a nice looking result, but it appears to be effective in addressing VTA adjustment. When laid underneath the 1.2 mm mat this raises the effective mat height to a bit over 2mm, which so far seems to preserve the character of the turntable better than any other attempt I have made at raising mat height. On thin records, high frequencies are less harsh and the lower frequencies are more solid. Laying this under the thicker stock 2mm mat for thin records seems to increase bass boominess.

I have tried cutting a shim like this from a cotton t-shirt and it had a negative effect on the sound.

I have recently tried the 3mm Achromat and the Herbie's Donut Mat 0.5mm as a shim over Rega stock wool mat, and in my opinion, both altered the character that I love about the Rega.

 

Just to clarify, the sweater I found at Goodwill is 100% merino wool, not blended with acrylic like the one in the link. I included the link to show the general style of sweater.