VPI Classic hum

Sorry Bassraptor, but not sure I understand your most recent posts. Does the new Classic also present the same hum problem? If so, I really find it hard to understand. I own a tricked-up Classic 1/2 plinth with a Classic 3 tone arm base and S-S wand. I've had two hum/bass ringing problems that were unrelated to the TT.

My first problem related to using a Grado cartridge, which is not news. A different cartridge fixed that problem.

The second problem related to a bass feedback loop relating to an "el-cheapo" IKEA kitchen table my wife gave me to put the TT on. The kitchen table is close to the speakers and transmitted a bass rumble into the TT. The "fix" was to mount the TT on a heavy maple butcher block board, which in turn was placed on two Styrofoam bricks. I have ideas for a better fix, which includes ditching the crummy kitchen table, but that's for later.

Bassraptor, I have no doubt that something is going on with your system. I just don't think it's a defect with the TT.

Hope you can sort it out.

Bifwynne... I've yet to set up and play the new Classic 1. My old Classic 1 had a problem. It's all explained in one of my posts following the original post. It was the TT itself. So I traded in that Classic for an Aries 3, which has been hum-free so far.

But I've still been lusting after a Classic. An opportunity emerged last week to get another one...the new version with the raised plinth... And I'm hoping it will be hum-free...

Glad to hear. Please let us know how you fare.

I'm a very occasional lurker at Audiogon, and I came upon this thread while looking into maybe upgrading from my VPI Scout Signature TT (with SDS speed control) to perhaps a Classic 3. As my handle suggests, I do studio quality LP to CD transfers and remasters, often for commercial release. The persistent, if very low level these days, 60 Hz hum I've gotten from the TT and cart (a Shure M97xE with a JICO SAS stylus; no better sound for anything like the money) is mostly what has driven my thoughts about an upgrade. (BTW, I can easily and precisely notch out any 60 Hz + harmonics hum with software so it's not in my finished product, but still...) While I haven't read every word of it, I've found this thread useful and edifying, and I thought I might add some different suggestions.

As implied, I don't use this TT for general listening. My system setup is such that the signal goes directly from the TT via unbalanced Monoprice ID#2680 RG-6/U 18AWG 75 Ohm Coaxial cable (I auditioned several interconnects up to $200/pair and none were as good, and for $7.50/pair!) to a Musical Fidelity M1ViNL phono stage directly connected with balanced cables to a Mytec Stereo96 ADC and then via Toslink to my DAW (Digital Audio Workstation). Thus I am able to very clearly SEE in real time with spectral analysis, as well as hear, exactly what I am getting and the effect of any change I make.

Cables, and their position, ARE important, and it's rather surprising how evident the microphonic effects can be when the cable from the TT is moved even slightly. Cabling is also a significant reason why I've been considering moving to a Classic 3, as that can be had with balanced outputs which have the potential to eliminate essentially all spurious RF and AC pickup.

But the other hum-killer that no one seems to have mentioned in this thread is balanced AC power. With balanced AC, instead of a 120v hot and 0v neutral leg as is normal, there is 60v 180º out-of-phase on BOTH AC legs, which will naturally cancel most AC noise. Converting one's system power to balanced AC is easy, but it requires a big, heavy, well-designed and expensive transformer, and prices start around $1500 and rapidly go up. Equi=Tech is hands down the best manufacturer of such equipment, and THEY AIN'T CHEAP at all, but boy is it worth it if AC hum is a problem. Their website is full of good and valuable information.

BTW, another often unnoticed source of AC hum are these damned compact fluorescent light bulbs. They'll generate a whole LOT of hash and can cause interference if they are anywhere near your equipment. Running them with balanced AC helps that tremendously as well.

A couple of things that no doubt go without saying around here, but I'll say them anyway. First, hum and RF pickup are completely separate and different issues from acoustic feedback problems. I don't have acoustic problems because I play my monitors at a very low level while transcribing an LP. Also, DO NOT LIFT GROUNDS, ever, which people sometimes do to fight hum. Proper grounding is important, including from the TT to the system, but it's especially important if balanced AC is being used. ALL modern electrical equipment is compatible with balanced AC, but if there is a fault, you could get hurt or worse if your grounding is improper.

Well, enough for now. Hope this helps.

RE" Meanwhile, let's hope this 31-month-old thread will finally stop cropping up!"

HA!

M~