VTF-2 Hummm

[SeeAlice]

I bought a VTF-2 through Ascend Speakers, prox 4-5 years ago, for a HT set up in my living room. Loved the Ascends and the VTF-2 from the start and never had any problems, until last night. I normally leave the VTF-2 power on (rocker switch) and power down my receiver. While getting ready for bed, I noticed an unusual loud humm and quickly traced it to the VTF-2 (receiver was completely off). Switch position and volume knob position have little effect on the humm. It sounds like a ground loop problem but I am using the two-prong plug adapter and have never noticed this problem before. The VTF-2 is plugged into a Monster Subwoofer surge arrester. I plan to try the VTF-2 tonight without the Monster surge arrestor. Any other suggestions?

[SeeAlice]

As a follow up: Last night when I turned on the power (rocker) switch to my VTF-2, the loud annoying humm had changed to a very loud modulated drumming (receiver was still powered off). The problem completely disappeared when I turned the VTF-2 power off and replaced the Monster subwoofer surge arrester. The surge arrester must have had something bollixed up in the MOV circuitry. I had no idea that a surge suppressor could cause that kind of problem with a subwoofer. Go figure.

Anyway, back to happy! :)

[Pete_Hsu]

Good to hear that it wasn't the sub!

[Ddavidson]

Being systematic (with step by step elimination ..... which is what you did) is the only way to get to the bottom of hummm's and noises. If nothing has changed in your system heat and age are normally to blame for newly developed noise. One of my old class a/b vtf3 amps (250w) had an humm issue after 5yrs or so of heat and abuse (a dry joint) but it was nothing too serious. Good to hear you solved yours even easier.


Ddavidson

[SeeAlice]

I have been on TDY for a few months and unable to use my HT. Long story short, the problem is back and worse than ever. My VTF-2 is apparently in need of repair. The powered on VTF-2 is silent, until it receives a signal from my Yamaha receiver. A loud LFE thumping sound is immediate.

No sub or receiver settings have any effect, except that volume changes increase thumping volume and the sub's phase toggle switch slightly alters (modulates) the thumping. I have checked cable connections, replaced the Monster sub surge protector, and eliminated the surge protector with no apparent change in condition. Unless a freakish failure of my receiver's sub output circuitry is to blame, it appears to be a problem with the VTF-2.

How do I go about repairing a VTF-2?

[feisty]

I had a similar problem. Talked to P. Hsu and he thought the amp. needed work. However, he suggested I try a new subwoofer cable, just in case the cable might be bad-although he did not think so. Went to Radio Shack, paid $4.99, replaced the existing cable and VOILA!-NO MORE NOISE!!!!It was the cable! Try it before you get into the hassle of retruning the amp. to HSU. It's cheap enough.:D :D :D :D :D

[jbuzz]

I have been on TDY for a few months and unable to use my HT. Long story short, the problem is back and worse than ever. My VTF-2 is apparently in need of repair. The powered on VTF-2 is silent, until it receives a signal from my Yamaha receiver. A loud LFE thumping sound is immediate.

No sub or receiver settings have any effect, except that volume changes increase thumping volume and the sub's phase toggle switch slightly alters (modulates) the thumping. I have checked cable connections, replaced the Monster sub surge protector, and eliminated the surge protector with no apparent change in condition. Unless a freakish failure of my receiver's sub output circuitry is to blame, it appears to be a problem with the VTF-2.

How do I go about repairing a VTF-2?

This post exactly describes the problem that started with my VTF-2 a few months ago. It's about 5 years old too and I've been using the cheater plug. I've had some time recently to try to diagnose it. There are times when it is unplugged from the receiver entirely and it begins to hum followed by the rapid thumping. There are times when I have to plug it into the receiver before it starts the hum and thump.

I am using a Monster sub woofer cable and it's plugged into the mono port on the VTF-2. I don't believe I've changed any of the toggles or settings from the factory.

I have a Denon AVR-3301CI receiver which I purchased recently. The sub woofer cable is plugged into the Pre-Out SW port. I have not changed any of the settings relating to crossover or anything else that I would think would affect the signal to the VTF-2. In fact, this problem began while using my old Denon receiver and I didn't change any of the audio settings on that amp either.

I can try another cheapo sub woofer cable but wouldn't the fact that it starts the hum and thump when it's not plugged into the receiver eliminate the cable?

[fourg63]

I can try another cheapo sub woofer cable but wouldn't the fact that it starts the hum and thump when it's not plugged into the receiver eliminate the cable?

Not entirely. Disconnect the cable from the sub. Does the hum and thump stop?