Dual 721 turntable - opinions/advice?

I'm not sure the Sumiko is a good match for the Dual ULM arm. I would stick with the AT120E and simply replace the stylus. I just sold a Dual with that same cartridge and the combo was very good. The Dual was designed in an era where high compliance cartridges were the norm. The opposite is true today. But the Ortofon OM series, as well as Ortofon's new 2M line and the Shure M97xE, are widely available and match well.

I have no direct experience with the 721 but I've had my share of Duals from that era (and with that same basic tonearm) and my guess is that the drive system is at least equal to that of your Akai and the arm is probably far superior. You traded up, especially considering you spent only $20.

As for the dustcover: You've heard of eBay, right? That would probably be your only shot, but any dustcover that old is going to be at least somewhat worn. So you might try buffing it out with plastic polishes like those from Novus or Meguiars. If it's really bad, it can be first wet sanded, then buffed. There are people who advertise dust cover restoration service, but the cost is somewhere around $100 plus shipping both ways.

So...$20 for the table, $50 for a new stylus unit, $7 for some plastic polish and rags and a few hours worth of elbow grease. For well under $100, I'd say you have a very nice turntable that should be comparable in at least some respects to the entry-level stuff of today. Enjoy.

Ekobesky,
Actually, I paid $10.

The dustcover is cracked all the way across the middle, side to side. And I know cosmetics are not critical to function, It would be nice if it looked better.

I don't understand "high compliance" or why the brand new Sumiko wouldn't be a good fit. I'd appreciate whatever you can do to educate me on this topic of matching tone-arms with cartridges. I was worried that the Shure or AT would be too bright for me in the highs. What is a "ULM" arm?

Craig

Phono cartridges have suspensions, just as cars do. If you were to put a very stuff suspension on a very lightweight car, the ride quality would be stiff and unbearable. Conversely, if you put a very compliant suspension on a heavy car, it would be squishy and prone to bottoming out.

The same is true for phono cartridges. The Dual ULM arm is Ultra Low Mass -- very lightweight. So, you need a cartridge that has a very compliant suspension so that is can be loaded properly. A low compliance cartridge will be too stiff, and it will introduce audible resonances.

Today, most tonearms are medium to high mass, and most cartridges are accordingly designed with stiffer suspensions. The Sumiko is best matched with medium mass arms. The Dual arm will likely not have enough mass to properly load the suspension...the cartridge will just sort of ride on top of the grooves. At best, it could sound like crap. At worst, it could possibly damage your LPs. Now, you could add extra weight to the headshell...but that defeats the purpose of the ULM concept.

Therefore, it would be best to stick with one of the cartridges I recommended. If you have a cheap phono stage, the Ortofon OM10 would be an appropriate solution as would the Shure M97xE. If you have a decent phono stage, then I would recommend the Ortofon 2M Red or a new stylus for the Audio-Technica. And if you have a better-than-average phono stage, it would not be unreasonable to suggest the Ortofon 2M Blue. I'm using one now on a Dual CS-505-3 and it sounds great.

In any event, the Audio-Technica AT120E is a more resolving cartridge with a finer stylus unit than the Sumiko so regardless of compatibility issues, replacing the AT120E stylus would be the cheapest path.

As far as the dustcover....it keeps the dust off, right? It's best to remove it anyway when listening. If you leave it up, it acts as a "sail" for resonances. If you put it down, it can allow static electricity to build up. Remove the hinges and rest it on top of the table so you can easily remove it during use. If you think of it as a dustcover rather than an aesthetic part of the turntable's design, then you can buy virtually any replacement that rests comfortably on top.

I really think you made a fine buy there. The fact that your Dual is still functioning as intended 30 years later speaks to its enduring quality. Like an old car, you have to put a little bit more effort into replacing parts (in this case, the cartridge) but assuming you use properly suitable replacements, there's no reason why the Dual can't sound good even by modern standards.

Thanks, very clear information.
Since the owner claimed that it "had a new needle", how can I evaluate the condition of the stylus?

My phono stage is a Proton 1100 preamp. It likely doesn't stack up against preamps in the multi-hundred dollar range, but my understanding is that the innards are essentially identical to a NAK of the same class. So, from what I gather, not a bad little pre.

Now what to do with the Sumiko cartridge.

Craig

I misspoke. My Proton 1100 is pretty much identical to a NAD 1130.

Is there a thread here to help a newbie evaluate the condition of a stylus?

Craig