Cheese said:
derekcohen said:
About a year ago, I went through a complete re-build of my Thorens TD150, re-build of a Rega RB300 arm, and still using a Supex 900 mkIV moving coil. The photo below includes a new vinyl top. The Jarrah bases are in an article on my website.
That's absolutely beautiful [member=4358]derekcohen[/member] ...did the solid wood plinth make a difference with the sound from the Thorens and if so, how would you characterize the change?
I'm also interested in your thoughts about your acrylic isolator base.
That goofy spring suspension seemed to always be an issue, sometimes too much and then sometimes not enough...I even tried to suspend the entire turntable from the ceiling with springs and that worked...until it didn't. [smile]
My apology, Matt. I'll answer this question, then hope the thread returns to your build.
The context for isolation is relevant. The drawers in the Jarrah campaign chests run the danger of resonating like speakers. The turntable sits on one, and vibrations could affect the turntable plinth, run along the arm to the cartridge. All this would muddy the sound. Resonance would be worse if the floors were suspended floor boards. Fortunately, they are solid Jarrah on concrete.
It is not only the turntable which is affected by vibration, but the audio components as well: amplifier, CD player, streamer. All these needed to be isolated.
The audio components sit on shelves in sorbothane isolation feet, and the shelves are decoupled from the case as they sit on pins.
The choice of acrylic for the turntable armboard is that it absorbs vibrations well - much better than MDF. The thick Jarrah plinth adds quite a bit of extra mass, and the platter and inside is damped with sound panels. The armboard is further protected from vibrations in the Thorens design, which uses springs as suspension. I spent quite a bit of time replacing the springs and then tuning the "bounce" optimally. The turntable uses IsaAcoustic IsoPucks as feet. Finally, the isolation platform is acrylic suspended to further isolate it from vibrations which may be transmitted via the cabinet.
As one can see, every aspect of the design of the turntable and the housing of audio components is geared towards minimising vibration and unwanted resonance.
Does it work? Well, I can tap quite forcefully on the cabinet and this does not affect the sound at all. Ditto the audio components. Of these, the CD player tray is susceptible to vibrations, and these impact on the stability of the laser.
The CD player is an Oppo Blu-Ray player. The amplifier is a Devialet Expert 120, the streamer is by Cambridge Audio CXN 2, and the speakers are Kef LS50 Meta with a Kef KC62 subwoofer. The cartridge is a Supex 900 mkIV. This is not an expensive system. I listen mainly to Jazz and Blues, and the sound is detailed, spacious and has great dimensionality.
I shall not go into the speaker cables, interconnects and mains cables, all custom made, as you will think me crazy
Regards from Perth
Derek
