Hoffman Amplifiers Tube Amplifier Forum
Other Stuff => Cabinets-Speakers => Topic started by: Rich on May 15, 2009, 10:23:11 pm
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Celestion Vintage 30 noisy
Bought this on eBay, looks like new. Installed it to try it out and I found it be noisy (hummmmm). Unplugged the guitar no change. Continued testing and noticed a popping, sputtering noise which lead me to believe I had a bad tube, but I plugged my old speaker back in and the amp ran fine so I plugged the 30 back in and the noise returned.
Any ideas what is wrong with the speaker?
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Could be a number of things:
1. VC rub. remove the speaker from the enclosure an place it on a table. gently move the cone in/out with your fingertips gently, and listen for any scraping noise.
2. loose lead connection. take a 1.5V C D or AA cell and touch it to the terminals with some wire- watch/listen as the come moves in and out. don't hold in for too long or the DC will heat up the VC. Sometimes a 9V transistor battery's terminals are spaced right so you can just touch it without any wires... You should hear a pop or thump as the cone accelerates in or out if you hear a scratching noise then the leads may be loose or damaged. look to see if the leads appear frayed or loose, may be fixable.
3. Intermittent short: Same test as #2, but the leads may be touching, or there is a scrape or other damage to the VC that causes it to be shorted out on the pole pieces or elsewhere in the motor.
If the speaker makes scratchy noises with both the battery and manually (fingertips) I would bet that the VC is loose and rubbing in the gap. If that is so, the speaker needs to be reconed and the VC replaced. It's tricky to do it yourself, but there are kits and instructions available for some of the more popular models. The parts have to be right or the parameters can change drastically. heavier cone and or coil will be more bassy and less efficient but handle more power... lighter cone & coil will have less bass and sound 'tinny' in comparason. The resistance (ohms) has to be right also.
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Celestion Vintage 30 noisy
Bought this on eBay, looks like new. Installed it to try it out and I found it be noisy (hummmmm). Unplugged the guitar no change. Continued testing and noticed a popping, sputtering noise which lead me to believe I had a bad tube, but I plugged my old speaker back in and the amp ran fine so I plugged the 30 back in and the noise returned.
Any ideas what is wrong with the speaker?
Is it a UK V30 or one from overseas? There is a difference in construction (glue instead of threaded bolts) I've heard. Is it a new speaker or used? Are you sure it's not a tube?
The reason I ask is because the V30 is a much louder speaker than most and tends to accentuate noises that other speakers cannot reproduce. I had a static/popping noise that was showing up in a V30 (1 x 12 combo amp). I found a pre-amp tube was rattling so bad that not only was it making the usual tingling sound hanging there, but it was cutting in and out electrically in concert with an "A" 440 note. Holding the tube to calm it stopped the popping in the V30. The noise did not show up in the same combo with the OEM speaker. I'd be very surprised if there's something wrong with the speaker, from your description I'd be looking for a tube, assuming of course that it's in a combo, where that V30 will batter many-a-tube to death, purely because that speaker is a shaker/mover. It happens to be my all time favorite.
-MM
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Is it a UK V30 or one from overseas? There is a difference in construction (glue instead of threaded bolts) I've heard. Is it a new speaker or used? Are you sure it's not a tube?
The reason I ask is because the V30 is a much louder speaker than most and tends to accentuate noises that other speakers cannot reproduce. I had a static/popping noise that was showing up in a V30 (1 x 12 combo amp). I found a pre-amp tube was rattling so bad that not only was it making the usual tingling sound hanging there, but it was cutting in and out electrically in concert with an "A" 440 note. Holding the tube to calm it stopped the popping in the V30. The noise did not show up in the same combo with the OEM speaker. I'd be very surprised if there's something wrong with the speaker, from your description I'd be looking for a tube, assuming of course that it's in a combo, where that V30 will batter many-a-tube to death, purely because that speaker is a shaker/mover. It happens to be my all time favorite.
-MM
MM I believe that your first sentence is absolutely correct and I have allowed myself to be mislead by the sensitivity of this speaker. It is picking up stuff the other speakers I've tried have totally missed.
There is a problem with the amp which has been driving me nuts from the get go, but I thought I had solved it.
Sorry about the bad post.