Cartridge - sweet spot on the cost/sound curve?

This Grado!

https://gradolabs.com/products/opus3

This Denon is a legend. I remember owning one in the 1980s.

Other companies mod them (Zu Audio?) and resell.

https://www.amazon.com/Denon-103-Moving-Coil-Cartridge/dp/B0027426UE/ref=pd_ci_mcx_mh_mcx_views_0_image?pd_rd_w=6nDWo&content-id=amzn1.sym.bb21fc54-1dd8-448e-92bb-2ddce187f4ac%3Aamzn1.symc.40e6a10e-cbc4-4fa5-81e3-4435ff64d03b&pf_rd_p=bb21fc54-1dd8-448e-92bb-2ddce187f4ac&pf_rd_r=DX32Z75V9A4RE0CRB3RD&pd_rd_wg=UecPo&pd_rd_r=fdef7760-d592-4f53-abb7-330fd3e4ba04&pd_rd_i=B0027426UE

I used a BPS for years before switching to an Audio Technica VM740ML and I have become an AT convert as a result. super affordable, with an easily replacable (and upgradable) stylus.

https://www.audio-technica.com/en-us/vm740ml

Time to play Sherlock Holmes, make notes

Imbalance: Assuming you are right, I would prove it is the cartridge, i.e. rule out other potential problems before I bought a new cartridge: Your phono: you have two sets of interconnects, and a variety of tubes in 2 devices and a specific preamp input that are all different than your digital source.

1. move the digital to the input you are using for your phono pre: still imbalanced, then it’s that input, not .... good, it’s somewhere in the phono chain, where exactly?

2. switch phono l and r, weak moves to the other side, tells you ......

3.

4.

Cartridge re-builders say the MAJORITY of cartridges they receive have had inaccurate anti-skate for years, uneven wear leads to uneven sound: the replacement needs to be right. Who will install/calibrate your new cartridge?

I also like AT MM cartridges with excellent sound and imaging specs (wide channel separation/tight channel balance) replaceable MicroLine stylus which have the largest contact surface, thus longest life and minimize wear on your grooves.

They track at 2.0g, I prefer lighter, and I prefer stiffer cantilever, I risk used vintage cartridges to get beryllium which is no longer used, recently bought two used AT, AT150e and AT160 bodies with ATN160ML stylus which track at 1.25g, each in your budget, but buying used cartridges is not for most people I know.

Swap the phono leads on your PS Audio phono to make sure the sound level issue reverses (to rule out an issue with the amp.)

EDIT: ^ Elliott got there before me!

Grado Prestige Green $125 is an easy recommendation.

I meant to say, when buying new, I prefer lighter/stiffer boron for cantilever material over aluminum

If your phono stage can handle low output moving coil cartridges a Denon DL 310 MK II can be had from a trusted seller 2Juki for $330. If higher output is needed then the Denon DL110 is in the low 200's. Output voltage is higher, but not as high as a typical moving magnet. You MIGHT have to add a bit of volume from where your typical volume setting was for the Sumiko cartridge, but it will work. These are the two most affordable moving coil cartridges I am aware of. Otherwise you are looking at moving magnets, typically the Audio Technica AT95 family, or the 540ml which costs in the mid to high $200's. 

@elliottbnewcombjr In the sub $500 new cartridge market I am interested in knowing what options there are for boron or other hybrid cantilevers. For awhile there was carbon fiber but that was more of a cheap as chips option for Audio Technica. 

@neonknight

The Nagaoka MP200 sports a nude elliptical on a boron cantilever, and is well within that range. It’s tougher to find, but I see an MP300H for very close to $500.

@elliottbnewcombjr In the sub $500 new cartridge market I am interested in knowing what options there are for boron or other hybrid cantilevers. For awhile there was carbon fiber but that was more of a cheap as chips option for Audio Technica.

Boron is not common at this price point, even used. Audio Technica makes one that’s (sort of) close - OC9XML, $600 new. There should be various used AT’s with boron out there. You can sometimes find a used Benz Ace or Glider at this price (boron, with either Fritz Gyger or Japanese MicroRidge stylus). A brand new Ace used to cost $550 (circa 2000s) but those days are gone and these models are no longer common.

That said - aluminum cantilevers can sound very, very good. Sometimes even preferable to boron, depending on the cartridge!

Everyone has their preferences.  As mulveling points out aluminum cantilevers can sound very good.  Personally, I tend to prefer them over other exotics such as boron or beryllium.  This is a personal taste thing, there is no right or wrong, just a matter of taste.  In your price range in addition to Audio Technica, excellent BTW, consider Ortofon, perhaps a 2M Bronze.  This assumes you determine that you do need a new cartridge after following Elliott's suggestions.

I have Goldring 1042 MM for my Nottingham Spacedeck/Spacearm. Bought it years ago from analogueseduction.net in the UK for $350. Now it is probably more, US prices are $600 or so. I doubt you will find an overall better cartridge in this price range. It does nothing wrong and many things right or I would've replaced it long ago.

I would get an Audio Technica VM540 MM cartridge.  It sounds fantastic and comes in around $280.00.  You will not be disappointed and I think sounds better than the Blue Point Soecial.  I owned one mounted on a Rega Planer3 turntable.   I found it thin and bright.  You could look into the Grado cartridges.  They have a moving iron cartridge for around $300.00.  

Grado at this level may give you a foggy unbalanced sound.

The Needleclinic NC-103 is less than $600 and it blows aways cartridges costing multiples of its price.

https://trackingangle.com/equipment/needle-clinics-denon-103-phono-cartridge

I swap between a NOS Shibata stylus equipped Audio Technica  AT 12sa and a Goldring E3. Both are MM's and the cost of both together is less than $500. I use the AT cartridge for older recordings as it will reveal more detail. The Goldring is used on newer, more balanced recordings as it has a very smooth midrange.I may go for the newer E4 stylus for the Goldring, when this one wears out.

Whatever you land on, remember to give it hours and hours of break in before you form an opinion. Often, I think people decide a cartridge sucks before they have heard it perform at its best. 

Happily, my 1st pick for a Moving Coil was/is a winner, and your Phono stage has MM and MC options

AT33PTG/II MC Microline on Tapered Boron: eBay $460.

I wore it out, bought a new one without hesitation (for 1/2 price from AT's trade-in program). 

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one method to get boron, is to buy a Shure V15 body, and a NEW Jico SAS on Boron

Shure V15V body, eBay $200.

Jico SAS on Boron $282.

It comes with the brush you can use up or down like the Shure originals, however, Shure's brushes were/are damped, Jico's is non-damped.

And, you can have VAS rebuild you a frankencartridge, I've got an advanced stylus Steve calls 'P', on boron, with Shure's OEM damped brush that I can use in either my 97x body or V15Vx body