Questions to ask as I shop for a tonearm?


I’ll be upgrading in 6+ mos. I’m asking now because I’m still learning. I want to take plenty of time to understand the relevant technical aspects of something so complicated & what makes one person love brand X & another person dislike it.

I have a George Warren tt & a Sumiko Blackbird cart I’m waiting for to put on the stock Rega 250. I’m also waiting for Christmas to hookup a Jolida JD9 mkII.  My budget will be ~$1500. While brand & model suggestions are appreciated... I want to learn about tonearms. As always, I appreciate the knowledge you all pass on to me.
tochsii
@toschsii,
You're being very smart to ask those questions. It's a complicated and often frustrating subject for some. You are lucky that there are many helpful experts here. I would suggest paying close attention to comments from
@almarg @raulariegas @nandric, @chakster, @lewm, @dgarretson, @atmashpere who all make regular contributions on this topic.

I'll mention one tonearm consideration that you should familiarize yourself with:
The relationship between tonearm and cartridge. Resonance is a big concern with a known and agreed upon range of what works best. Too low a resonant frequency or too high will cause huge problems in sound quality and tracking ability. vinylengine sit has a resonance calculator that is a well-known tool that lets you consider the compatibility of any given cartridge and tonearm. It's not perfect, but it is a perfect place to start to understand the concepts and get lead you in the right direction. Pair a cartridge and tonearm that lead you to a resonance in the green range. One quirk is that Japanese companies present different specs than most Euro or US ones, so if considering a Japanese cart, by sure to convert the specs so you get "apples to apples". (This will make more sense after a bit of reading). 

Though not about tonearms, another important aspect to understand is the relationship between cartridge output and phono stage gain. Carts put out very small signals. Phono stages, or phono sections of preamps that have them built-in, add a certain amount of additional gain(often adjustable). To get reasonable performance you need to have enough gain but not too much. Some very low output carts needs an extra boost(step up transformer). Moving magnet carts need less gain, moving coils more. Many phono stages are made to focus on one or the other, some both. Making sure your phono stage has appropriate gain settings and loading options for the cartridge is a critical step to enjoying vinyl.

I'm sure plenty will chime in with good advice Cheers,
Spencer
Have you asked the manufacturer what arms they believe, works well with their table?

Shouldnt they should be the most qualified, I hope so!
I don’t think any of the modern arms under $1500 can do it better than classic japanese tonearms. Here is what i am using along to some others which does not fit into your price tag.

These arms are all under $1500:

Lustre GST-801 - with two different counterweights and additional ringweight is fine for many cartridges from mid compliance MM to high mass low compliance MC. Magnetic tracking force and anti-skating, silver wiring, vta on the fly.

SONY PUA-7 - very easy to use/adjust for many cartridges, comes with additional sub-weight for heavy MC. Just make sure the arm has its VTA on the fly and armrest like this.

Technics EPA-100 - also very easy to use for MM cartridges and some lightweight MC, rubby ball bearings, unique counterweight with dynamic damping option. Many info online. Not good for heavy headshells and heavy cartridges! Great tonearm.  

Victor UA-7082 - long version of the popular UA-7045, very nice tonearm with vta on the fly, easy to use and adjust quickly. One of my favorites. Designed for the best DD turntable made by Victor/JVC (TT-101).

Denon DA-401 for high compliance MM cartridges only !

P.S. It depends on your cartridge, but you can’t go wrong with any of the arms from this list. Highly recommended!
These are all good recommendations. The best bang for the buck in a new arm is unequivocally the new Jelco 550. Even better is the 850.
You might look into the existing mounting and its options. Most arms require specific mounting distances fron the center if the platter. This is called the pivot to spindle distance specified in millimeters. 
sbank thanks for all the info & especially the tips on whose comments to pay attention to. 

Thanks everyone 

To mount any tonearm you need Dr.Feickert protractor with precision Pivot to Spindle ruler. I bought mine from these guys (without VAT the price was sweet).
I would only choose a tonearm that can be adjustable in all needed parameters.....weight of cartridge, height, overhang, azimuth.
@stringreen azimuth and overhang can be adjusted on the removable headshell, all tonearms (except denon) in my list (for example) have VTA on the fly.

Many tonearms does not have this options and must be avoided in my opinion, especially most of the modern tonearms, don’t forget that price range extimated to $1500 by the OP. Tonearms without removable headshell, but with azimuth on the fly, cost 3 times as much (such as Reed).
My advice for any newbie is to buy a complete turntable... And save what may become a long, expensive and painful lesson in what can go wrong buying a separate tonearm.  
For folks with experience, or who have a mentor, great. Without either... Yikes!                           
So I say stick to a ready made pairing of a great table which comes WITH THE ARM.                          
Thank me later.        
Good luck.                  
PS I have been at this a long long time, and I would not consider buying a separate arm unless it was like one of the very best, Kuzma 4 point etc.. And that mainly because they only come as a separate purchase a lot of the time. Anything cheaper.. you can get a good ready made together.And if I did, the arm would be added by a pro.. Not some tinker.

The main function of a tonearm is to register the cartridge in the record groove, and to maintain this registration as the stylus transits the record.

This is accomplished by allowing fine adjustments to be made, and having those adjustments remain stable. Resonance is also an issue.

Enter Trans-Fi Terminator air bearing tonearm, a superb tonearm within your price range. I own two of them, both on high end turntables, one a commercial product, one a DIY air bearing. They are highly adjustable, stable, and exceedingly "tweakable". I have had good results with a light MM and with a higher end Koetsu, just by changing the tonearm mass with weights and adding damping.

The only problem is that the tonearm does not work with a suspended turntable, because the beam of the tonearm must be absolutely horizontal for the air bearing to work. Since neither of my TT is suspended (they sit on a concrete foundation bedded in rock far from heavy equipment), the Trans-Fi is ideal for me.

Good luck!
I've had a Grace 707 arm of 20 years and sold it; Maplenoll Ariadne air bearing arm/ turntable--the best I've had for sound up to now;  VPI Scout w/ arm; VPI Classic w/ arm; Avid Diva II w/ Origin Live Silver II arm; Super Lenco TT w/ OL Silver II arm; And then the same Lenco TT w/ Trans-Fi Terminator arm with all the upgrades.  The Lenco w/ Terminator was the overall second best set-up.  It did have the best dynamics and clarity of all of them.  I'll second the Trans-Fi Terminator for overall sound and use.  VERY TOUGH to find a TFT on the used market.  Mine was $1275 with everything including all parts of the air pump and delivery system.  I was hoping to at least equal the Maplenoll TT/ arm in sound and have it be less potentially dangerous to the cantilever in the air went out.  NEVER a problem with the TFT as it requires very little air to float the arm.

May have one for sale in the very near future.  I had to spend quite a bit more to beat the TFT.

Bob
@dorkwad TFT is back on sale apparently.  I think it may be too much for the OP to deal with.
@elizabeth The OP inherited the table and it's pretty decent except it comes with weak Rega 250 arm which s/he wants to change out. 
Check out the Jelco line of tonearms as they fall right in your budget and offer performance above your budget.
@tochsii - Some options...

If you are looking at  rega arm, then take a look at the Audiomods arms...

http://www.audiomods.co.uk/

Jeff at Audiomods, will take note of your turntable/cartridge and make an arm that matches.

He uses a rega arm tube, but that is where all similarity to Rega arms ends. Everything else is built by him to a very high standard and level of performance. 

I would recommend the one piece silver litz tonearm wire and the VTA micrometer Adjustment options.

This is probably the last tonearm I will ever purchase

There are other Rega-like options available - like this one from Michell
http://www.michell-engineering.co.uk/tonearms/

If you decide on the Rega offering, then I would recommend the Cardas One piece harness. This was my first tonearm tweak and it performed really well compared to the stock Rega wire

Hope this helps in your quest - Steve

@williewonka Thanks for that post. I just bought an Audiomods V, which is at Sota to be mounted on the new Series Six Nova they are building for me now. My hunt (discussed in another thread) came down to the Audiomods or the new Jelco 850, 950s.  I am one who adjusts VTA for every LP played. An aftermarket VTA adjustment base made specifically for the Jelcos ~$200, kept it under consideration. The Audiomods has their own built-in micrometer as an option. A great deal on a pre-owned Audiomods w/micrometer from a fellow 'Goner made it an easy decision for me.

The Trans-Fi Terminator was something else I considered. Having spent plenty of time with a friends' TFT, I just couldn't get comfortable with its tweakiness and apparent fragility. The delicate exposed wiring scared me a bit. Had more than one visit where "TFT down again, let's listen to digital". Lately he's worked through his issues and is very pleased. While the micrometer VTA has some appeal, the digital display reminded of a $5 tool from Harbor Freight. The large dial was also more awkward adjusting than you'd expect and inferior to the dials on other VTA adjusters like those on VPIs or the terrific one on the Technics EPA series that I used to own.   

Someone correct me if I'm wrong, but I thought I read that the Michell arm mentioned is made for them by Jelco, as are a number of other companies' arms. If so, that would make me think that a Jelco branded arm might be a better value...conjecture sure, but perhaps worth consideration. Cheers,
Spencer
Another Japanese arm to consider is the Fidelity Research FR 64 FX. On the heavy side, not really suitable for high-compliance carts, but a really great arm at the price.
Seconded on the FR64fx, if you're interested in moving to medium compliance MC carts. It's a phenomenal match for low-compliance carts like all Koetsus and the Red/Blue/Bronze in the Ortofon Cadenza line. It can also be a great match for many medium-compliance carts, which is most MC's. Great build quality and bearings. 
I like the FR64fx, but the price is way over $1500 budget considered by the OP 
That’s not my impression of 64fx pricing, given some patience. Now if you’re looking for a super-clean/mint example with box and all accessories and don’t want to wait for a hot deal, then sure it’s going to be north of 1500. These are quite old arms, and even though they hold up very well, the typical example shouldn’t be costing a fortune.

If you find a nice example without a headshell, then go for it. That's one premium you don't need to be paying; the FR headshells aren’t great anyways. Silver or copper wiring - both sound fine.
 the FR headshells aren’t great anyways.

There is a great FR headshell: model RS-141 is my favorite

See there’s already a really nice looking FR64fx posted by TMR today, within the op’s stated 1500 budget. I have no affiliation to that seller but I am a satisfied customer - I think they are very good on their item descriptions and stated operational condition. No headshell, but that’s easily remedied. Includes the very rare heavy counterweight. 

I think that’s a tasty deal for someone bold enough to give this classic arm a shot!