Hey everyone. Wondering if anyone has run into this. Please read my entire post before offering comment/suggestion
So i have just purchased a Stellar Phono, Clear Audio Performance DC, Tracer Tone Arm, and Concerto V2 MC. And while it sounds excellent I get woofer pumping (Rumble). I have tried isolation feet, isolation platform, placing my table on the floor, Moving my table to another room via xlr. Took my table to the dealer and hooked it up to his system and… Nothing, zip, nodda… The only thing that stops the rumble is switching phono preamps. Has anyone else run into this at all? Very very frustrating!
This sounds like a classic example of tonearm cartridge resonance. If it is, an isolation platform, isolation feet, etc wouldn’t eliminate it. Which is what you’ve observed. Tonearm resonance is a fact of life, it is simply the physics of the suspension system of the cartridge interacting with the mass of the arm. All tonearm/cartridge combinations resonate, it is not a symptom of a malfunctioning turntable. Some phono preamplifiers include a subsonic rumble filter to cut out the resonance, some do not. That is a choice typically made by the designer based on what makes sense for the best sonic performance of the phono pre. Be careful about jumping to conclusions based on what you found using a completely different phono pre at the dealer. I wouldn’t be surprised if it has a rumble filter. I have some minor pumping with my Rega Aura, a very high end phono pre built end to end for sheer sonic purity minus any signal path filtering. I ignore it. It is of no consequence. I think, PSA can confirm, the stellar phono has no subsonic filter. I suggest you not fret about it unless it has any some detrimental sonic impact. If it still bothers you, you can buy after market rumble filters to cut it.
Also, two forms of isolation can DECREASE the isolation…you might have overdone it! Audio freaks aren’t picking up on this, but earthquake engineers certainly know it.
It doesn’t matter that the tonearm and cartridge are both made by Clearaudio. All tonearms have a natural resonance with all cartridges. The frequency of the resonance is determined just by the combined mass of the tonearm+cartridge and the compliance of the cartridge. It is typically below 10Hz. You can calculate it yourself. And I’ll point out again isolation devices don’t defeat it. Which is what you found. A rumble filter can notch it out.
As I assume the Stellar usually has a built in rumble filter, you could check with the service dept. if something’s wrong with it. The fact that you don’t have problems with other phono amps would let me search within the amplification chain. Maybe also try a different following amp combination.
I saw pumping bass chassis too, somewhere long time ago, but really can’t remember why.
A short call at Clearaudio or a look into the arm and cartridge specs should make clear that they fit. Not all Clearaudio combinations do (e.g. if you have a linear tracking arm)… For the moment I assume they fit in your case.
besides the root cause to rumble other trying to solve, I would similarly as @jazznut suggest to check with PS Audio if Stellar Phono does have rumble filter included/enaged (basically filtering of ultra-low infrasonic frequencies). It is not solving the root cause, but might relieve your issue with infrasonic bass getting into your woofers. Maybe @DarrenMyers might chime in?
Yes i have checked on vinyl engine using the resonance evaluator and they should work together without issue. I contacted clearaudio to make 100% sure that they are able to work together but have not heard back yet.
