Sujet Help : Panne sur AD120VT

Citation : Reliability: 4
This is where the amp let me down.


I had the amp only for a few weeks and the amp would randomly turn itself off, sometimes it would come back on after a few seconds, sometimes I would have to flick the power switch off and then on again.
This was an intermittent fault that would only happen every few rehearsals.
After looking into the problems with Valvetronics amps, it seems that many of them are faulty.


Reliability of Chinese made electrics and overall quality control is poor in many many cases.


Damn Vox for moving production out of the UK.

Citation : Customer Support: 4
I sent the amp back to get fixed, but they reckon there is no fault occurring. Ofcourse because it is an intermittent fault. They wouldn't test the amp for at least a few hours, understandabley, but where does that leave me?


I will not rely on an amp that is unreliable. Make sense?


From my modest research into Valvetronics reliability, you would think that the service department would be able to isolate the causes of common faults and know how to test and rectify such problems.

Overall Rating: 5
What it comes down to is: No professional musician is going to use an unreliable product, are they?

Citation : This is the one area that concerns me after reading some of the other reviews about the amp and some problems that people had with earlier versions of the amp

Citation : Reliability: 1
Ok. This is where I have something to say. In my earlier review, I praised this amp for it's features and sound quality. I had also said that I was concerned about some of the other reviews regarding the reliability and was wondering if I was next on list of unfortunate schmucks. Well, after only 65 days of limited home use the left speaker just cut out permanetly. I recall someone else mentioning this as well. The major retail outfit whom I purchased this from (their initials are G.C.) would not swap it out for another one on the floor because this happened after the 60 day cut-off even though I have dropped around 4K + there. Fortuantly I bought the extended protection plan which covers parts, labor and shipping. It only takes one bad experience for me with a product name or retailer to leave a bad tast in my mouth. My confidence in Vox is at the bottom. If this were just an isolated case that's one thing. But it would seem that I am not alone in my relaibility issues. I will say this however. I have a Roland MicorCube practice amp which I play through every night in front of the TV just to stay in practice and it never gives me any grief. I had a Roland Jazz Chorus years ago which again, never let me down. But I was led to the Vox by the Salesman which in retrospect was a mistake. Should have Kept walking towards the Roland when I entered the store. Come on Vox. You have been making amplifiers for ever. What's so difficult about making one that won't take a crap after a couple of months. It's not exactly Astro Physics you idiots.

Customer Support: N/A
We'll find out I guess.

Citation : Reliability: 1
This is why I'm leaving a review. Had the same speaker cutting in/out problem as everyone else after a year or two. I was sunk, and was ready to trash this thing, but tried the Deoxit Spray and jumpering solution mentioned several times. Low and behold this FIXED THE PROBLEM......FOR A WHILE.... For two months after this, it worked great, like new again. Now, there's a ridicously loud crackling hiss sound that has somehow developed. The spray/jumpering has no effect on this. Looks like I've ran out of options. This is a MAJOR P.O.S.

Customer Support: 1
J-O-K-E

Citation : Reliability: 1
OMG! Where to start!
If you want to gig with this amp FORGET IT!
Here goes my story.


Bought 1 and half years ago, within a year both speakers barely worked, smoke came out of the top of the amp at the gig, cannot express how gutted i felt.
After that they had a crackle, fizzing sound and would be very quiet so I replaced them with some Celestion GT12s and it worked again.. Yay
Then shortly after that (few months) the amp would break up at loud volumes. Still haven't sorted that out.
And last week the left speaker stopped working.


I'm sure this time though that the speaker is okay, its probably something inside the amp which is only sending the signal to one speaker.




Customer Support: N/A
Not bothered with them after hearing what others have already said

Citation : Reliability: 4
Very poor. I, as many other people did, experienced the problem of sound cutting in and out and left speaker problems. This is very fustrating, as I love the sound of this amp.


This is the main reason why I decided to post, I always had my amp at 60w. I changed it to 30w and now it WORKS FINE. For the moment anyway. I'm looking forward to seeing how it handles with the band this saturday though.


If this amp was more reliable it would be a dream machine, sadly it lets it down.

Citation : I got the amp one week ago, and this weekend I started to test it at home.
I was NOT impressed by the loudness..even in my living room fully cranked up, I expeted a bit more output with 2X60 Watt.. so I went closer with my ears and noticed that the right speaker is only half as loud as the left and also lacks in sound-quality.


In my opinion both speaker should sound similary in soundquality and loudness - but they do not! - I don¿t know why - is that normal???




Reliability: N/A
I¿ll have to send it back before I¿m getting started.


And I wonder what¿s the better choice - ask for money back? or getting it repaired.
I think it would be a great amp for me, but what¿s the point to wait for a repair and get it back with the same or even another flaw.

Customer Support: N/A
I bought the amp in Germany via the internet.
There was no Vox Warranty in the package but in Germany we¿ve got a 24 month kind of warranty by the seller so a solution for repair or replacement should be worked out by my dealer with his distributor

Citation : Reliability: 1
Here we go again. I've had this for a year and half without worries. I started becoming a bit skeptical about all the bad reliability issues I saw in HC (only really really happy or really really disgruntled people post....right?). But, then it happened to me.... About three weeks ago, the sound started cutting in and out. I tried some of the home remidies suggested in this forum, and got it working again at max volume for a few days, and then it started cutting in and out again. Vox has a major design flaw in this amp. They REFUSE to acknowledge it, as I've emailed them about it. But, when a large percentage of folks who've posted here have experienced the same exact thing, it is pretty obvious. For all you folks who gave high marks for reliability, I wonder how many of you waited a year or two before posting? This is a trainwreck.

Customer Support: 1
I've tried contacting them via email with no sucess. They don't acknowledge that there's a design flaw with this. Opening up the back, and looking at the circuit boards, it looks pretty shoddy (I have an EE background...). Such a waste for such a good sounding amp. The warranty is a joke.

Citation : Reliability: 2
This is the amps downfall. Mine went wrong a few months after purchase with one channel (It's a stereo amp) cutting out. As it was out of warranty I took it apart and fixed it myself. I wasn't impressed with what I found and I can see why so many others are having problems.


The cabinet isn't strong enough and allows to much movment, this means the actual metal enclosure the electronics are housed in sags down causing the mains transformer to hit the speaker if the amp is set down roughly.


The electronic construction is also pretty poor and is built like this.


At the top you have the Korg REMs pre-amp board. This is made quite well with reasonable soldering and good intelligent PCB layout. After this however it's all down hillz


Below the Korg REMS board you have another quite small PCB for jack sockets and stuff. Not much to go wrong here but the jack sockets are also switches in the signal chain so problems will arise due to poor contact. If you do get problems spray some WD40 on an old guitar lead and push it in and out a few times to clean the inside of the socket.
The socket for the footswitch is an Ethernet socket, normally used for network cables and totally unsuitable for use on this type of product. Yes, it gives a lot of connections in a small socket footprint but it won't withstand constant gigging.


Finally we have the main power amp PCB with their "Valve Reactor" technolgy. This PCB is where most problems will arise from. The soldering is sub standard, mine had several bad joints.


Some of the audio signal wires are tied with cable ties to the A.C output of the mains transformer, no wonder the things noisy.


The valves (2 x 12AX7) are hung upside down from the PCB meaning they work loose when the amp is moved around.


Not enough thought has been given to protect some components against damage through over heating. Some of the tranistors in the driver stage get too hot due to no heat sinks being used. The main output transistors are on a huge heatsink so no problems there. It is not good design to put 2 X transformers and 2 x valves on the same PCB. This is done for cheapness, built to a price rather than a standard.