Need advice on a good Phono preamp

I currently have a Music hall 5 with upgraded kimber wires .
It has a new Benz Micro Gold Low output moving coil cartridge.

I have currently a low cost opera audio PPM-6 Phono preamp.
I get a low hum in the speakers and it does not seem to do the job.

I can sell it for a loss to move it and can invest up to 700.00 US for a used phono that works well with a low output MC .5MV....

Or should I just sell the cartrige and buy another MM or High output MC???

I used a PS audio PCA2 preamp and a Halo A-21 Parasound paired with Revel Preforma 30's. I listen to rock and jazz.

I use good Nordost and cardas cables.

Thanks in advance for any info......

I am having very good results with a Bob's Devices step up transformer. Runs $395 and has improved even phono stages that do not supposedly need it. There is a good review on 10 Audio site. I liked the Dynavector 75 and Blue Circle ones so well I became a dealer for them. The 75 is $750 new and considerably less if you can find one used. Blue Circle has some minimalist ones that look strange but are high value for money. Very good deals come up on occasion on others, too many possibilities to advise on.
I have a Lehmann "Black Cube" that is fantastic. It is a VERY detailed phono pre and fits exactly in your $700 budget. It also has adjustable loading for MC and an input for MM. It may also be upgraded down the road. I used it with a LYRA Argo-i cartridge and a VPI Scoutmaster. is VERY quiet!!
I have been extremely happy with a Heed Quasar that I got as a demo for $750. It works great with a .3mv Dynavector.
The Nova Phonomena uses rechargeable batteries D/C(it charges them itself) eliminating line hums etc. and can be run A/C if you want. It is also very adjustable affording a wide choice of cartridges. There is one at auction on AgoN presently that should be in your $ range.
Look at the Marchand in kit form or built which is said to be great. Also, the EAR 834 is a classic, but MC may be an issue. jallen
Try your best, maybe add something that you've allocated but go with Benz PP1. They will work like Bonny and Clyde:-)
The cheaper version but very well designed is Michell ISO(designed by Tom Evans) which sells used ~$300. The only inconvenience with this model that you'll have to solder a proper load resistance for your cartridge.
I tried the Nova Phenomena and the PS Audio but it just didn't have the warm sound I was looking for. Having heard all my records through a Conrade Johnson for many years and now using Rogue mono blocks, I was looking for something different. The George Wright P200 is a downright steal and a super bass sensitive tube phono amp. Not only did it have more slam, it was pretty darn quite too. It's a 2 part phono amp with separate power and output. I use Synergistic Research Looking glass out the output source. Separate balance controls so you can match it up with MM or MC cartridges and straight to your amp without running it through a preamp. Works great with my Project 9.
I agree with Zeal that the Wright P200 is an excellent unit, especially for the price. But you are going to have to look for a used one because George Wright passed away last month.
Jolida JD9 Tube phono pre-amp. Can accomodate both MC and MM cartridges, adjustable gain, and sounds gorgeous. 6moons highly rated! Saw one for sale here for $375