Hifi Pig talks to Hifi Pig reader Stuart Armstrong who has an interesting and very accomplished DIY turntable project.
Hifi Pig: Introduce yourself to our readers
Stuart: I am an Electrician by trade and have been for about 25 years…I have also been an audiophile as long as I can remember and DIY speaker cable ect. builder…I would consider my turntable custom design build an achievement that ranks with the best contenders in its weight class.
Hifi Pig: Tell us a little about your turntable history. What commercial tables have you owned?
Stuart: My first turntable was a Pioneer pl 7 bought new in 1980 I think. Just after the advent of the compact disc I purchased a Revolver after reading a magazine review and had a Shure V 15vmr installed and never looked back. I owned a handmedown CD player for a while but when it stopped working properly I never replaced it and I only had a handful of CD’s. After a good friend gave me an AutoCAD program and taught me the basics of it I began designing different turntable concepts. Years passed but I kept plugging away with the Idea of custom building a high end deck.
Hifi Pig: What other DIY turntables have you made? (If none what other tinkering/DIY have you done?)
Stuart: That was my first. It took me a long time to complete as I wanted something that would succeed design wise and would be an upgrade from the Revolver. Before I was building speaker cables from 25 pair cat 6 and terminating them into two channel speaker system and still use. I custom build interconnect cables as well. Speaker and turntable stands I made from wood and steel. Extensive speaker Mods to a set of Infinity RSB’s that I no longer use.
Hifi Pig: Where did the concept for your DIY design come from?
Stuart: I observed other designs like Micro Seiki DQX 1000 and Clear Audio Solution turntables. I designed my turntable to accommodate both arm board types to make it as versatile as possible. It two can accommodate up to three tone arms.
Hifi Pig: Tell readers about the design ideas behind the turntable and the problems you’ve faced along the way
Stuart: After several designs I decided to keep things simple yet versatile. The main foot assembly/arm board support parts consist of only four parts per foot (not including arm board and bolts). There is no suspended suspension in this design relying on choice of materials, mass and plinth design to control resonance. The platter alone is 30 pounds of solid aluminium and is 2 1/2” thick. Light weight suspended designs tend to act like a large microphone and will feed back when stereo is at high volume. It’s is because the light turntable will be free to resonate on a suspension. It is much harder for acoustic energy to excite a resonance in a massive deck that is directly coupled to a rigid stand. If I tap hard the plinth or arm board with two fingers on my turntable being played loud you will barely notice any feed back. The problems I faced along the way you ask? Well there is plenty in all areas of custom design and build. Sourcing materials and finding a good machinist to make parts is a big one. Expense is high as you might expect being a custom build. The platter and bearing assembly alone set me back 2K$ Canadian. There were other issues with fitting foot bolt parts but I think that was a pretty minor setback compared to what other people have experienced. I think I got lucky in most respects and for the most part this project was a success!
Hifi Pig: What’s the drive mechanism on the turntable and why did you choose that system?
Stuart: The drive was a combination DC motor and controller custom built (height) in one rectangle box and was also supplied with two rubber string belts manufactured by Space Tech Labs. Versatile but motor hasn’t enough torque and power to run the heavy platter properly. I have to leave platter drive on for a while just to warm up platter bearing and leave on continuous for the record playing session. Space Tech Labs digital drive system is noisy but not noticeable when playing music. Build and parts quality could improve some and speed needs to be adjusted by ear more often. I do intend to one day design/build a motor/controller system but that itself is a large undertaking.
Hifi Pig: How many hours have you spent designing and constructing the turntable and how much do you think it has cost you in total?
Stuart: Never kept track but countless nights on the computer just designing and drawing. It doesn’t matter how long it takes when you design because that’s the most important part of building anything to perfection. The parts were all made by different specialists in their field. My cost for everything that I personally designed (bearing assembly was partially designed by Choir Audio) to basic turntable (no motor/controller, no armboard and no arm/cartridge) About $5,200 dollars Canadian.
Hifi Pig: What turntables have you compared your design to and how do you feel it performs in comparison?
Stuart: My first audiophile turntable the Revolver (early non rebel version) was my first audiophile deck and remained so for along time beating just about any cd player. I still own it. Needs a new belt, but still works great. My custom turntable was built with bettering the Revolver in mind. Aside from the AC motor having a more consistent speed in the Revolver I succeeded. My brothers refined system includes a VPI scoutmaster or Aries. Although there is many factors that will affect the way a system will sound a turntable can be the most important reason why a stereo can sound so good. Even though the arm that I had mounted was a vintage gimbal (circa 1970) Japanese Sound Audio that I picked up for $350, he thought it was a better sounding deck than his.
Hifi Pig: Where next? Do you plan any other DIY projects?
Stuart:I am currently designing a linear tracking arm of massive proportions (no air design). Its a major undertaking and I don’t think it will be complete before next spring…thats the project I want to complete next but there are others…I am keen on different speaker concepts as well.
Hifi Pig: What kind of speakers?
Stuart: I have this floor stander idea that is tall narrow with support by circular column on either side of a line of open baffle drivers…that’s all I will say for now on that subject.
Thanks for speaking with Hifi Pig and all the best with your future projects.