Tonearm compatibility and advice

Dear Vinyl Gurus,

Does the spindle-to-pivot distance determine whether an arm fits a particular table? Or is the needle-to-pivot the determining factor? Or does the headshell adjustment allow you to make up for small mismatches?

The tonearm mounting hole on my table is exactly 222 mm from the center of the hole to the spindle. I was considering a Hadcock GH 228 Export, but I'm confused whether it will work with my table. The spindle to pivot distance for the Hadcock is 212.8 mm, which is 9 mm short, but the needle to pivot distance is specified as 228.6 mm which will make the needle overhang by 6.6 mm.

I would greatly appreciate help understanding this geometry stuff. More specifically, will this arm work with my table? Thanks in advance.

For what it's worth:

TT spindle to center of mounting hole: 222 mm
TT arm mounting diameter: 22 mm
Hadcock GH 228 spindle to pivot: 212.8 mm
Hadcock GH 228 pivot base diameter: ~15 mm
Hadcock GH 228 specs
My table specs
Yours is a standard Rega hole. A Schroeder Model 2 will fit, as will a unipivot Magnepan and a bunch of other tonearms, if you decide against the Hadcock.

You may be able to squeeze by with the Hadcock, depending on the headshell slots and the particular cartridge, but it would be better if you could slot the hole for a proper fit. There are SME type mounts around that can provide an attractive solution. The ADC ASB-1 sliding base is one, but it is a rare beast, and I don't know the hole diameter without looking it up. Anyway, if you happen to be in the US, I may be able to hook you up with a guy who can make a clone of it that matches the Hadcock shaft for a halfway decent price.
Thanks Mosin.

You're right. It's a standard Rega spindle-to-pivot distance (222 mm). About a year ago I swapped the original arm (MA-707) for a modified RB300 (Tecnoweight and Cardas wire). I used Turntable Basics protractor to align the cartridge and I'm confident it's dialed in. But the end result is that it doesn't create the kind of spaciousness I've heard on other tables. This is why I'm considering a better tonearm altogether like the Hadcock. My cart is a nude DL-103. Maybe I should stick with the original tonearm and live with it until I upgrade the whole table.

Any suggestions?
I have two of the ADC bases left over from my days as an audio dealer. I have no idea what they are worth.

I was a user and a proponent of the Turntable Basics protractor for many years, for Rega style arms and others.

Recently, Audogon member Palasr helped spread the word about a new protractor offered by After resisting for a while (mostly out of stubbornness) I succumbed to the many positive reports and bought one.

The sonic improvement was amazing. Before you change tonearms, cartridges, I'd suggest buying one yourself. I suspect you'll hear much of what you're looking for once your cartridge is accurately aligned and the TTB, handy as it is, is not precise enough to align a cartridge accurately.

Be aware that the Mint is both tonearm and turntable specific. If you change either you'd have to order another Mint. You can read some of the many testimonials here:

wouldn't the Arc style protractor put the alignment off if the pivot to spindle distance isn't perfectly accurate (222mm vs. 223mm)?

On another note, the Denon DL103 is a less than perfect match to a Hadcock 228 arm, due to the low compliance of the Denon. You may try but results may be mixed. the Hadcock should work better with a higher compliance cartridge. Bill (Audiofeil) would know.

Finally, yes, the Schroeder No.2 can be mounted on a Rega (or Rega style) turntable. Mounting diameter for the No.2 arm is 20 mm for the standard No.2 and 23mm for the No.2 fw (only available with DPS table). The 20 mm version can be mounted on a standard Rega table with the mounting collar supplied with the No.2 arm.


"I have two of the ADC bases left over from my days as an audio dealer. I have no idea what they are worth."

They sell for more than you might think. The last one I saw went for around $75.
Mingles, it's difficult to know what is causing your lack of air and spaciousness. Could be the table, arm/cartridge or table/arm/cartridge combo. My highly modded Thorens with modded Rega arm and Denon 103r has a similar lack of spaciousness compared to my VPI Scoutmaster. I'm still in the midst of voicing in this tt setup so I haven't come to any definite conclusions.

Your problem also could be with tt isolation, I just finished up some aluminum top plates for my DIY sandboxes, haven't listened to Thorens with this top plate yet. It did markedly increase air and spaciousness with the VPI so I expect it will do the same with Thorens.

The suggestion for MintLp is also right on. I previously aligned my cartridge on VPI with VPI jig and DB protractor, the MintLp was a nice improvement. I will eventually get around to this with the Thorens.
Thanks for all the thoughtful replies.

Doug, I appreciate your Mint Tractor suggestion. I saw the thread when it unfolded and wondered if the hype was anywhere near reality. I'll take another look. This might be my best option right now.

Rene, thanks for pointing out the mismatch with the Hadcock and DL-103. I knew it wasn't ideal. I was planning to upgrade carts if I purchased the GH228.

Sns, very interesting. I've been spending time at a friend's house who has a VPI HW-19IV, Moerch UP-4 and Dynavector DV20XH. His playback is much smoother, more coherent and spacious than mine. In the past, he owned similar speakers and electronics as I do, so he knows my system isn't living up to its potential. It might be the DL-103. Or, as you suggest, it might be the tt/arm/cart combo. Maybe I can have him bring his table to my house so I can test this theory.

I'd like get some opinions on the RB300. I want to now if I'm wasting my time with it. I realize it's an entry level arm with flaws, but I get the impression from some folks in the forums that it's not worth the metal it was forged with. I'm exaggerating, but some folks really dislike it. When I removed the Micro Seiki MA-707 and held it in my hand next to the RB300, I couldn't help but notice how the 707 was so much more precisely engineered. The craftsmanship is leaps and bounds better than the Rega. It's been out of my system for a while and I forget how it sounds. I plan to re-install it soon.

I want to improve my vinyl system, and I'm trying to figure out the best way to do that. I'm open to considering anything... a new arm, a new cart, a new table. But maybe I should start with reinstalling the MA-707 and getting a Mint Tractor.
The low compliance DL 103 would also be a poor match with the afore-suggested Magnepan Unipivot.

The Mint is indeed designed for an arm mounted at the designed pivot-to-spindle distance, and is useless for any other distance. My OL Silver (Rega clone) was designed for 222mm. Regas can be mounted at that distance AFAIK. Whether it would be optimal with a Mint I'd leave up to Yip (the maker). He'd give honest advice.

I agree the Denon 103 is poorly suited for a Hadcock. Good observation. Frankly, if air and spaciousness were high on my list of sonic goals a Denon 103 wouldn't be among the first cartridges I'd choose. On the right arm it's a great performer, especially for the money, but its strengths lie elsewhere.


Another (cheap) tweak to consider for a Rega/103 combo is the Strange Tonearm Tweak. This ingenious device, which you can DIY for about $5, made my $1K OL Silver sound like a $3K tonearm. Even better, the tweak was designed specifically for a Denon 103/Rega combination.

Nothing you can do will give you as much bang for your buck, and it's fun and highly educational too. I can't recommend that old discussion thread strongly enough. The author's enthusiasm and knowledge are what pulled me back into vinyl (and that's cost me about $20K, so be careful who you listen to!).
Frankly, if air and spaciousness were high on my list of sonic goals a Denon 103 wouldn't be among the first cartridges I'd choose.
Doug, with spaciousness in mind, using an RB300, what cartridges would you consider in the less than $600 category.
If you like Denon, the 304 is thought by many overseas to be their best cart. in many respects. It is compatable with the Rega arm [I use one in my SME IV on a Basis Ovation] and should be around your price range.It is a very good cartridge.
Hi Stanwal, I'm sure the 304 is an excellent cartridge, but I feel the need to try something other than a Denon. I had a DL-160 for many years and currently have a 103 and a 103R. I'm ready for a change. Previous carts I've owned are Grado Sonata, Benz Glider L2 nude, Roksan Corus. I'm also familiar with my friend's Dynavector DV-20XH and like it quite a bit.

I bought the Mint Tractor today and had it configured for the MA-707 arm. I'm going to pull out the RB300. I'd like to rewire the 707, but it doesn't look like an easy project. I have no idea how the bearing comes apart. I don't want to break it. I may just stick with the original 25 year-old wire.