7th Circle Audio J99 500 series vs Hardy twin servo pre

No experience with the 7th Circle Audio 500 series stuff but there’s also the Radial Twin Servo, which has Jensen input and output transformers like the Hardy

I have the rack mount two channel Hardy Twin Servo, it's the "Sony edition" which has the switched gain settings for precision matching: nice to have but standard potentiometer version probably great too.

I actually bought it used from somebody on RGO (who has years of experience with them for classical work) - I really like mine. Not much to it though, it's basically just not-boring not-clinical but clean gain. No regret buying it on my part. I don't think Hardy himself ever actually released a 500 series version. Unfortunately, I have no experience with the other 500 series Twin-Servo options from Radial, etc. - first step is getting those super high-end transformers from Jensen and you can buy after market (legit) Hardy 990 opamps but if you're going that far it seems reasonable to just trust John Hardy's attention to detail when it comes to the power-supply design, PCB, etc. and go full in. Just my opinion, of course.

I have heard rumors that they are harder to buy new these days though - unconfirmed.

-Chris

Radial was Jensen's biggest customer and bought Jensen and then Radial was bought by Regimen Equity Partners, who like typical private equity dingbats jacked up the price to cover their cost of purchase, causing them to lose a lot of business. I guess to try to sell transformer DIs to every bedroom musician but active dis are better and most of the bedroom guys are DIing into an interface or playing fleawatt amps.

Jensen was never quick, actually I know quite a few who feel back when they had OEM’s winding to their specs they were quicker.
I do wonder how many who are now using “ their own transformers” have spec’d a slight change to stock Jensen & have an OEM winding them. Good winding machines are not cheap.

Another failure of the us government to prevent offshoring, costing Americans real jobs and livelihoods to enrich someone in a suit somewhere. I hope their former employees start something like Austrian Audio that does it better.

Of course the existential question is since this also applies to the Jensen pre is it still a Jensen if the transformer isn’t a Jensen?

😂 enjoy!

Also, here’s a video of him giving some history about his involvement with Deane Jensen’s design:

I've never A/B'ed the M1/M2 vs. Twin Servo but I'd imagine they are probably quite similar sounding pres. Part of my reason for buying the Twin Servo specifically was just my appreciation of the circuit from my university days - it's hard to say if there is any serious audible difference between them, especially at lower gain levels (where the servo more or less avoids the use of a coupling capacitor EDIT: both M1/M2 and Twin-Servo employ servo circuit to remove offset - they are seemingly very similar aside from number of stages).

No complaints about the Twin Servo on my end, but if a low-channel count version of the M1 or M2 came up locally (used) at a reasonable price, I'd be very tempted. Would be interesting to compare. 

I know you have a lot of experience with ribbons and old school transformer based everything, can you recommend a pre for ribbons that kicks but? Also, Isn't a differential pre with 78db of gain with no caps in the signal path close to a "free pass" regardless of trans ratio?

I can’t necessarily recommend anything for ribbons because I don’t own anything that’s readily available, only old crusty stuff. Just saying it works well and frequently outperforms others because of the transformer gain - as opposed to the Hardy’s advantage with high gain mics.