Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems In praise of old Meridian actives

Like many of us, I have a system made up of some old bits of hifi in my office ... which based on the amount of time I spend at work, probably gets more use than the main system at home, lol.

As is always the case, it's had a few upgrades as interesting bits of kit appear for cheap prices on the local auction sites. It's built around a pair of 1993-vintage M60s, which I think are the Mk II version as they have balanced inputs; they were being sold by a guy on behalf of his now-deceased Uncle, who'd bought them new from the UK. The power supplies had been treated to capacitor replacements in the last few years, but I was literally the only person interested in them - so the price was remarkably low for a lovely pair of actives.

A few weeks ago a 1996-era Audio Research LS-9 solid state balanced preamp came up, and it was definitely on the affordable side as most of the Audio Research fans seem focused on the tube models. I snapped it up on the basis of the fully balanced inputs and outputs, and after procuring a bunch of cables an old MS600 now feeds balanced in to the LS-9 which feeds balanced out to the M60s. Roon supplies the streams.

And doesn't it all sound lovely. The whole assembly is delightfully musical with clean separation of instruments, and has nice solid 3D imaging - which is a very nice thing to have whilst sitting at my desk. It has an extended bottom end but not the control of a good set of DSPs, and there's some sparkle missing from the top end, which is probably down to the tweeters needing ferrofluid replacement. And given the system is using the DACs from the MS600, I'm contemplating replacing its SMPS with an LPS - if I can find something suitably slimline that will fit in the case, that is.

I can definitely hear the difference that 30 years of technology has made with the 218/G65/DSP5200s system at home – there's a degree of finesse and nuance that the old M60s just can't get close to .. but as a system to have running during a work day, it's great. And most days, after getting into work and pressing play on Roon, I'm truly delighted by the music.

There's no particular point to this little rant, other than to say how much pleasure I'm finding in that old pair of M60s.

Cheers

They are, indeed, superb.

You will find a big improvement replacing tweeters.

Consider, if not already done, replacing the load resistors to prevent future issues.

Also, different capacitors will sound different, which were used when caps were replaced?

You might also find you are source-limited. The MS600 was, in my opinion, overrated.

The top end is definitely recessed, so either ferrofluid replacement or new tweeters would seem to be a good idea. I’m not feeling confident about doing the ferrofluid myself but I can definitely manage a tweeter swap … any idea what I need? I presume it’s an Audax unit … ?

The MS600 uses a lot of hardware to achieve fairly pedestrian performance, but it does have the advantage of being cheap - one of the primary criteria for a 90s-era system in the office. Interestingly, it does out-perform a WIIM Pro via Roon, but the WIIM is only a few hundred dollars so that’s not a high bar to get over. But I am thinking an LPS might improve matters, if I can find something slim enough to fit in that ridiculously over-engineered case.

the M60 started off with the Seas H398 tweeter

https://www.flickr.com/photos/190748481@N07/50520527057/in/dateposted-public/


https://www.seas.no/images/stories/vintage/pdfdataheet/h0398_25tafg.pdf

https://www.Meridian-audio.info/public/technote_tn29_-_m60_tweeter_identification%5b4013%5d.pdf

later changed to the H539

Rgds
Stuart

Thanks Stuart - I'd found the Meridian tech note on identifying the tweeters, and they're definitely using the H539 ... plus your thread on changing the ferrofluid is exceptionally useful, so I might give that a shot. Do you happen to know if there's a modern equivalent of the H539 from SEAS if the ferrofluid change doesn't sort out the issue?

Cheers

most replacements would be of a different sensitivity which would be easier to deal with on a DSP as the output can be adjusted in a configuration mode, much more difficult on the older actives as you would need to modify the output of the amp board.

Rgds
Stuart

Yeah, I'm assuming there isn't a drop-in replacement, so I thought I'd contact SEAS to see what they recommend - and then adjust for sensitivity and/or frequency response in the Roon DSP. It's not a perfect approach, but it's worth a try for a system this old.

In the case off a higher sensitivity tweeter combined with the older actives one could use a voltage divider/ dampening network between amp and tweeter consisting off a resistor in series with the tweeter and another in parallel. A calculator for the right values can be found here.