VH2 FX loop hiss and Channel Switching Issues

[Anxiety Serum]

I get a airflow sound, like an HVAC vent running coming out of my amp.

I isolated the amp using a single patch cable from Send to Return, and the resulting HVAC hiss scales directly in volume with the front-panel Master Volume control. If I plug in with no FX loop there is no hiss, but its not any pedal given the above single patch cable and no pedal.

Also, sometimes when I try to switch channels it won't. I have a video of me hitting the foot switch and the channel blue lights ping ponging back and forth.

This is what A.I. said about my symptons. The "ping-ponging" blue lights combined with your FX loop hiss confirms that your Diezel VH2 has a failing internal control microchip/switching logic board. But who knows if that is correct.

I just emailed this to Diezel, but thought I'd post here too.

The channels do switch now and I have had the channel switching issue intermitanlty in the past (returned my orginal VH2 shortly after I bought it, as it failed to switch at all after a few weeks). But I've had this one for years now.


Vidoes of both issues.

https://photos.app.goo.gl/wdyFKCbZkNnk4iE28

https://photos.app.goo.gl/NJs13wsmwRnki9JN8

 

[Solarflares]

Off the top of my head, it sounds like your fx-loop buffers have issues. This will require replacement parts, and possibly calibration. If the fx-loop is valve-driven, then perhaps a simple faulty valve. Don’t go tapping anything. Test a valve in V1 of another amp.
For a manufacturer to suggest a customer takes the back off a live amp with issues, and start tapping around - this is highly irresponsible and downright dangerous. A stray wire could suddenly contact plate voltage, and it’s goodnight.
For the switching issue. The best place to start is on Peter’s bench, and I would hope he could offer you immediate attention, and offset at least some of the shipping expense - given that this is not a brand new amp.

I’m not privy to your previous communications with Peter. But since he has reached out here - then let’s start from the beginning Peter, and address your reliability issues in a timely and respectful manner.

 

[Vin Diezel]

Of course, Germany is on its way to reaching US levels of education and stupidity very soon. Maybe Germans will be even leading the way into total idiocracy if we look at what has been happening for about 20 years in this country.
The older generation, however, is still very aware pets should not be microwaved and circuits should only be touched with insulating materials.
Tapping a power tube is survivable if you are not mentally retarded.

 

[Solarflares]

Of course, Germany is on its way to reaching US levels of education and stupidity very soon. Maybe Germans will be even leading the way into total idiocracy if we look at what has been happening for about 20 years in this country.
The older generation, however, is still very aware pets should not be microwaved and circuits should only be touched with insulating materials.
Tapping a power tube is survivable if you are not mentally retarded.

Where did you spring from? Germany? What are you on?
90% of valve-related amp problems come from people tapping hot valves. Did you know that?
Asking an unqualified customer to remove a back-panel is not on.

 

[Vin Diezel]

Removing the back plate does not expose the circuit.
Audio valve amplifiers do not even have front or back plates and the tubes are freely accessible.
Nevertheless, nobody pulls out tubes while the amp is running and touches the contacts inside the tube sockets with a metal wire in order to be electrocuted. What are you on?

 

[Solarflares]

If the amp has a fault, which in this case it does - it belongs on a test-bench.
Not switched on and live, with an inexperienced guy poking around in his bedroom.
I’ve seen a few amps take out other gear as they literally go bang.
There’s 500VDC in those bottles, separated from you by thin glass, and you want to go tapping it?

 

[Techdeth]

 

[Vin Diezel]

If the amp has a fault, which in this case it does - it belongs on a test-bench.
Not switched on, with an inexperienced guy poking around in his bedroom.
I’ve seen a few amps take out other gear as they literally go bang.
There’s 500VDC in those bottles, separated from you by thin glass, and you want to go tapping it?

I have never been part of the "I'll tap my tubes until they go bad because my amp just works fine and that bothers me"-crowd. ;-)

 

[Anxiety Serum]

Yeah I had emailed Diezels customers support and posted here at the same time in case it was a quick Do It Yourself home fix, that someone could walk me through. I'm in the USA, so shipping to Diezel in GE is probably out of the question (not cost efficent).

Sounds like I need a tech to look at it. I am definitely in the camp of unqualified customer, but before I go looking for one of those, again just wanted to see if anyone had any quick fixes. Clearly 2 seperate issues (switching and FX loop noise). Maybe they are connected maybe not. I hadn't changed my setup at all and the noise just appeared the last few days. Thought a pedal might have gone bad or a faulty pedal cable, but it makes the noise even if I connect new and working cable into the send and return with no pedal (noise goes away when I uplug the patch cable). So I know its not a pedal driving the issue.

I'm not trying to make a stink for Diezel. I love my VH2. Just looking for advice before I ship or lug this off to an amp tech who may more may not be able to fix it.

 

[Solarflares]

Yeah I had emailed Diezels customers support and posted here at the same time in case it was a quick Do It Yourself home fix, that someone could walk me through. I'm in the USA, so shipping to Diezel in GE is probably out of the question (not cost efficent).

Sounds like I need a tech to look at it. I am definitely in the camp of unqualified customer, but before I go looking for one of those, again just wanted to see if anyone had any quick fixes. Clearly 2 seperate issues (switching and FX loop noise). Maybe they are connected maybe not. I hadn't changed my setup at all and the noise just appeared the last few days. Thought a pedal might have gone bad or a faulty pedal cable, but it makes the noise even if I connect new and working cable into the send and return with no pedal (noise goes away when I uplug the patch cable). So I know its not a pedal driving the issue.

I'm not trying to make a stink for Diezel. I love my VH2. Just looking for advice before I ship or lug this off to an amp tech who may more may not be able to fix it.

If Peter is willing to be consulted during the process, and can provide schematics on demand - then any decent tech could fix your amp.
The switching could be a relay diode going rogue, causing relay contact-bounce. A bad relay is a possibility, as they wear quick if not damped properly by a functioning diode.
The hiss is almost certainly requiring the fx-loop driver and return stages to be isolated and checked

 

[Solarflares]

At this point, it is fair to point out that Peter Deisel has deleted his post on this thread.
Why, is anyone’s guess. Although it was a little dismissive I thought, and not befitting someone who makes a living by selling expensive niche product.
I have urged the OP privately to request a schematic from Peter, and to take the amp to a local tech.
Myself, I felt at the very least that Peter should have confirmed publicly that the amp would receive his attention if it was shipped to his facility. I think that’s what we’d all expect and hope for in this situation.

 

[Vin Diezel]

I do not know who is the tech in the US, but Peter is always very helpful and will help solve the problem in no time.