Right but I don't want to add some cables and plugs.
Or there is a way to power that extra fan when you switch the amp on?
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Ampeg SVT-II appreciation thread
- Thread starter i_got_a_mohawk
- Start date
Or there is a way to power that extra fan when you switch the amp on?
I just plugged it into an adapter.
That's beyond my pay grade.
@Wasnex is pretty cluey in these things
I am sure a tech could figure it out.
You can't wire the fan straight to the power switch unless the fan is designed to run on the line voltage in your country. SVTs run a 120V fan on 120V and 240V. This is done by strapping the power leads across one of the primary windings of the power transformer.
A DC fan will require extra power the amp is not designed to supply.
I added DC fans on one of my tube heads, but they run off a wallwart plugged into the aux AC outlet on the back. The outlet is not switched so the fans come on when power is supplied to the amp.
For a rack you can use a switched rack power module to control the fan.
Maybe I could also use the line used to feed the stock fan?
I'm aware this will reduce it's air flow as it could spin slower but with the extra fan, it could increase the air flow?
But I have read an extra fan is not useful. I think I've read that here from the designer himself.
How would you describe the difference?
I haven't had the chance to use my II pro onstage yet unfortunatly. That's why am asking
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More headroom with the svt. Dynamics in playing are better.
The amp when overdriven is warmer sounding.
The acoustic is cool though. We are loud enough i can just play in that nasty overdriven solid state space the whole time. But if I step on a fuzz pedal it has minimal effect since the head is already all out. Load the frontend of the svtII with a hotter signal and it just gets brutal.
Not sure if this particular amp has AC or DC supply to the tube heating filaments, but it's usually low voltage (~5-15 Volts) and could be used for a fan. If so, the fan will start as soon as you power up the amp (even in standby (no anode voltage)).
Edit: It's 6.3 Volts AC. Not sure how common that is for fans. Probably not very.
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I reviewed an SVT II schematic and could not find the fan.
The fan is on the schematic that has the ac termination board. Polarity switch. Ac power terminal, standby, etc.
The fan is hooked up on the primary side of the power transformer. The specific connections vary by line voltage configuration so that the fan always receives the same voltage. AFAIK its a 120V fan. If this is correct, I believe it would be safe to tap another similar 120V fan into the same connection. I don't think it should have any impact on how fast the internal fan runs. This is something a tech should be able to do. I don't recommend attempting to do it if your not a tech.
Yes, it seems to be connected and running as soon as the power is switched on. And there is only the main 10A fuse, so there should be no problem connecting whatever fan you want.
I also agree that one should not fiddle with these things unless you know what you're doing! Even if 120 Volts is generally not deadly, the 450 Volt B+ definitely is.
Just got this last week, 2nd time owning one of these. I had a later version about 20 years ago that I got off a neighbor with a 4x10 and 1x15(IIRC $1,200 for the whole rig), but regretably sold it around 2009. I never forgot how cool this amp sounded, really missed having it. I haven't plugged it in yet(I don't have a cab yet)but I noticed today a 12ax7 preamp tube was floating around loosely in amp. Might be a dumb question, but should I open it up to see if any tubes are missing? Would it cause harm plugging it in if any are removed? Thanks
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Yeah take the too cover off and check. All the small tubes are labelled on the chassis where they go.
Was the amp sold as working? The tube may have simply worked it's way out. Align the pins and rock it back in.
If preamp tubes are missing, there may be a reason. The amp may have damage. Also all of the preamp tubes are required for the amp to pass a signal. Can you turn the amp on with one preamp tube missing? Probably but what is the point. Maybe the fan and indicator lights turn on....or maybe the amp lets out a big cloud of magic smoke. If you don't know whether the amp is working, take it to a tech.
If the missing tube is a driver, you should know that they control bias for the output tubes. Each driver controls three of the output tubes. If a driver is missing, the associated output tubes should be biased off.
If output tubes are missing then it's probably best to take the amp to tech if you don't know why or what you are doing.
It was sold as working, it was listed on both GC and Musicians Friend sites. I will open it up later today or tomorrow and see before plugging it in. It wasn't packed very well when I got it, just a bunch of bubble wrap in a cardboard box, so hopefully it wasn't damaged. Either way, I will be taking it in over the next few months to have it assessed by a tech for whatever it will need, I did notice dust inside the graphic eq, so at the very least it might need a good cleaning. Thanks for the reply!!
