Gyro for Mono & Stereo

a space odyssey
Post Reply
blakep
senior member
senior member
Posts: 642
Joined: 06 Nov 2006 02:01

Gyro for Mono & Stereo

Post by blakep » 19 Nov 2016 23:57

Some big changes in the past few weeks with my table. I've had the urge for a while now to do a "mono setup" after hearing a really nice one earlier this year and looking through my collection and finding close to a hundred mono recordings.

I figured I could do one relatively inexpensively (maybe about a grand) but it turned out to cost next to nothing. Under $100 as I had literally everything laying around in storage.

My 80's Gyrodec actually had the subchassis pre-drilled for a second arm in the rear left corner where the motor was mounted and the plinth was pre-drilled in the front left corner so that the motor could be repositioned there. When I upgraded tonearms about 7 years ago, I put the Sumiko FT3 I was previously using in storage, along with its armboard. I also had a fairly heavily modified Denon 103R (aluminum body, potted, Soundsmith ruby cantilever and Line Contact Stylus) in storage as a spare cartridge.

When I took the FT3 out of storage I discovered that it was a little sloppy and in need of having the bearings adjusted. I tried desperately to find someone who could work on the arm locally with absolutely no luck. In doing a search online I found a post from a member at the Steve Hoffman forum who had a friend do the same kind of work for him on his MMT. I contacted Bruce and he very graciously contacted his friend Adrian who agreed to do the adjustment for me on my FT3 (with me paying him for his work of course). So I drove the arm down to Adrian (a couple of hours away from me) and he did a bang up job putting the FT3 into perfect shape for me.

I then strapped the 103R for mono using a bit of 47 Labs OTA wire I had kicking around, moved the motor on my table and mounted the FT3 with its older armboard and the Denon on the rear left part of the subchassis of the Gyro. I also went through my closet and discovered that I had another balanced tonearm cable kicking around there (my phono pre is balanced in and out); I had originally intended to buy a dedicated budget phono pre for the mono arm/cartridge, along with another tonearm lead, but finding the tonearm lead allowed me to go this way with no further financial outlay. The only draw back is that I need to switch tonearm cables when I'm playing mono records which is really not a big deal. My phono pre has infinitely adjustable gain between 55 and 75 dB so it is also a simple matter of adjusting gain for the two different (mono and stereo) cartridges.

The setup works and sounds great on the monos I have-it is without question better than playing them with a stereo cartridge. Once I had everything together though I had a bit of a problem. My Gyro is quite old (although upgraded for the most part to current spec-the Gyro is great that way and the Michell upgrades over the years have been pretty cost effective when you look at the price of many modern tables) and is not a Spider-it is a plinthed Gyro with a pretty substantial solid acrylic plinth.

When I mounted the second (mono) arm I discovered that things were a bit precarious at the rear of the table, where things were quite cramped and the upright rear section of the plinth sat just high enough to allow the body of the Denon to clear it if the arm was swung into its armrest and locked in but not high enough to allow the stylus and cantilever to clear. In other words, one false move and my 103R was going to have no more cantilever and stylus.

So I took the plinth and dustcover to a plastics fabricator that had made me a custom dustcover a number of years ago to replace the original beat up one I'd been using for quite some time. Had them cut out a section of the rear plinth as well as a section of the rear of the dustcover to allow the arm/cartridge to be mounted comfortably at the rear of the table without any possible interference from plinth or dustcover. The one downside is that a very small area at the rear will be susceptible to a bit more dust invasion when the dustcover is on, but I'd rather deal with that than a snapped cantilever.

Now rediscovering all the monos in my collection. They are sounding much better and very good.
Attachments
Gyro with Dustcover.jpg
(227.64 KiB) Downloaded 483 times
Gyro with cutout.jpg
(230.48 KiB) Downloaded 491 times

Werner
long player
long player
Posts: 1346
Joined: 31 May 2002 00:00
Location: Antwerpen

Re: Gyro for Mono & Stereo

Post by Werner » 21 Nov 2016 07:49

Very nice job, and a beautiful MkII GyroDec!

blakep
senior member
senior member
Posts: 642
Joined: 06 Nov 2006 02:01

Re: Gyro for Mono & Stereo

Post by blakep » 21 Nov 2016 22:56

Thanks Werner, and thanks so much for your online manuals/history/information. It's been a valuable resource to me over the years.

My Gyro probably started life as a late Mk0 or very early MkI. I acquired it around 1985 at a police auction selling stolen equipment (mainly bicycles) for next to nothing and had to put a bit of money into it (there was no power supply with the table when I bought it and it also had the soft feet on it which I changed immediately at that time) but it was still a great bargain and has served me well for over 30 years now.

It is serial #543, which, from other info I've seen on line on other Gyros, would probably indicate a manufacture date sometime in '83. Originally came with soft feet as I mentioned and two belts, aluminum bearing. The springs were not fixed to the subchassis though, so it's possible it started life as kind of a Mk0/Mk1 hybrid.

I upgraded to the newer platter, inverted bearing and decoupled suspension posts about 10 years ago and it is still running strong with its original AC motor!

I lucked out in terms of it being set up for two tonearms in terms of my recent adventure with it.

Apart from the upgrades 10-12 years ago, have changed the springs on it a couple of times in 30 years and replaced a capacitor on the motor. That's it!

A great design and a great table!

Post Reply