• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

My Ampeg SVT Classic keeps going into emergency standby mode?

Timpala

Timpala

Nov 13, 2011
230
14
IOWA
#1
I'm pretty sure it's my new Fender Modern Classic Telecaster Bass making it do it too. It has a nice fat sounding mudbucker that is really hot. I have basically turned down my gain and bass to the point of non existence. But, after playing hard rock & roll for about 20 minutes, the amp once again goes into emergency standby mode. I have adjusted the pickup pole pieces as low as I can.

I really love the tone and want to keep the bass. But if it keeps making my amp go into standby mode, that won't work. Any suggestions?
 
#3
It doesn't do it with my P-Bass or Jazz Bass. I'm pretty sure the hot pickups in the Tele are driving the tubes hard and the amp is trying to protect itself and save the tubes by going into standby mode. I have been playing the Amp through 2 15" cabs. I notice the sound getting more overdriven the longer and faster I play. If I can't keep the bass from making the amp do this, I am either going to have to get new pickups or sell the bass.
 
#4
Make certain your amp is driving into the correct impedance and if that's not the problem, you may not be hearing all the very low frequency the amp is required to produce with that bass.
So back the bass control off on the amp a bit.
There may be a slightly damaged output tube in there too.
 
#6
I'm sure if I played in a quiet band that I would have no problems. However, we play loud. Its hard to test the new settings when at practice because it takes a while for the amp to cool off. Of course when I am playing without the band, it never cuts out. There is so much beef in the sound of this bass, that I really don't need much bass dialed in on the amp. I do cut it a lot. Does anyone think that it could have anything to do with my speaker cabinet selection? I am using 2 Ampeg 15" individual cabs. I do have an 8x10, but I usually prefer the 2 15's. From what I have read, the 15 inch cabs should handle the lows better than the 8x10. Just another note. I did some research and found somewhere that the Fender pickups that are used in this bass are wound to 20k.
 
#8
It's funny you ask about the -15db jack. I have never used that jack because all of my basses are passive. I have been plugging into the 0 input just like I do all of my basses. However, I just had the thought just before I read the last post, that I should indeed be plugging into the -15db input jack. Having never used the jack input, how does it actually effect the settings? I hope I am having one of those "Ah Haaa" moments and that this would take care of my issue.
 
#9
I still don't understand why overdriving a tube preamp would cause a shutdown.
As asked above; are you positive the head and cab don't have an impedence mismatch?
 
#10
The head and cab would have to be really mismatched to just shut off. I ran a 6 ohm cab on 4 ohms for over a year before a power tube failed. It never once pushed into standby only to be fine when cool.

OP that is a padded input, all it does is decrease the input volume. It is not only for active basses, though they are generally the only time you need it. I find the -15 is a little much to pad but if you are clipping the amp hard it is your only option. I would imagine your issue wouldn't persist through that jack.
 
#12
After Bill Hughes, the inventor of the SVT, said that SVT's can take an 8 ohm load no sweat, I doubt it's an impedance mismatch causing it. I'm with those that say your power tubes have seen better days. But I guess we'll see what happens when your tech takes a look at it.
 
#13
When the amp goes into "Emergency Standby Mode" as opposed to just "Standby", the light flashes red & green. It does it because it senses something wrong. I have had the gain set really high and I have had it set really low. It just takes longer to cut out when I have the gain set low (barely even on). I can guarantee it is not my eq settings.

I am going to wager that I need new tubes. This new bass probably drove them over the cliff. :D
 
#16
I always keep an eye on the bias lights in the back and adjust them when needed. I have not tried plugging into the -15db yet. It sounds like it wouldn't make much of a difference according to other posts. But, I will try it anyway. However, I will probably take the head in before our next practice.
 
#18
How long has it been since the tubes have been changed? And if it's been awhile, be prepared to take out a small bank loan as they're not cheap.
 
#19
Bim1959 said:
How long has it been since the tubes have been changed? And if it's been awhile, be prepared to take out a small bank loan as they're not cheap.
Click to expand...

Ha! Ha! Yes, I do remember how much the cost of tubes were 8 years ago. I hope they haven't gone up much. I am sure I will spend more re-tubing than I paid for the bass. (insert sad trombone noise here)
 

Latest posts

Top Bottom
Back