Headroom on amps

[Asyd309]

Hey guys. I have an Ibanez SRX 5 string, and i love it to death. However, the output on this bass is so hot, it clips the imput of my Ampeg SVT 3 everytime, and it causes the speakers to fart.

I run the bass into a rack-tuner, and from the tuner to a Tech21 Sansamp, and from the Sansamp into the Ampeg.

This bass is great, but now I think I need to find a new amp with more headroom to take in the hot output from the bass. Any suggestions ? I don't know where to start.

[bassmancrv]

hey man, clipping shouldnt have anything to do with your bass... how many watts is your amp? unless its like 10 your only clipping cause youve got your input gain up to high, try turning your gain nob down less than the volume nob, or else youll over drive it and im guessing its a SS amp so clipping is not good

[Asyd309]

The Ampeg SVT is rated for 450 watts. I do have the gain set at like 3 o'clock, but thats how I like the tone. But I have to compete with two Mesa Boogie Trip Rec's in the band, and it's a real power struggle sometimes.

I turn up the master volume to about 3 oclock also for my stage volume, and thats when the cabinet starts to distort.

[enim]

What cab is it?

[edgebass5]

Okay, you're potentially talking about two different things, or both at the same time.

Potential #1:
Okay, the SRX is an active bass, in other words you're sending a high output, low impedance signal from your source. From there you're going into a tuner and then into a Sansamp. The Sansamp is essentially the second preamp in your chain (your bass' onboard pre being the first). Now, the output of your bass is going to be somewhere in the ballpark of 100-250mV. You're putting it into the Sansamp and depending on the settings potentially boosting that output again, possibly to a level over 300mV. By the time the signal hits your SVT-3 it could simply have so much output voltage that you clip the Ampeg's preamp and the resulting tone comes out of your speakers.

Solution: Try this; Take your bass and plug it directly into the input on the front of the Ampeg head and make sure that the input pad button is set for its -db setting. Now, take your tuner and plug its input into the "tuner out" on the back panel of the Ampeg. Finally, take the Sansamp and plug its input into the "effects send" on the back panel, and the Sansamp's output into the "effects return" on the back panel of the Ampeg. This will lower the voltage hitting the front of your preamp, and coincidentally will also be a much lower noise/truer signal method to deliver your tone to your speaker cabinet.

Potential #2:
Since you're trying to compete with two half stacks (maybe full stacks, you didn't say) with a single amp you might just be cranking up your amp to achieve a competing volume, but run out of clean headroom. At this point, your power amp will begin to clip and send DC (direct current) through your speaker cabinet. This is definitely the most damaging thing you can do to a cabinet. DC eats up speakers like a crackhead in a buffet line.

Solution: Try different EQ settings that focus more on the midrange and less on the bass. This will help you cut through better and won't eat up as much power from your power amp, and therefore increase headroom. The alternative to changing your EQ is to increase the size of your power amp by either adding a second power amp from a company like QSC, Crown, Crest, etc. Or simply buy a larger head.

[Asyd309]

Thanks for the advice Edge. Your sage-like wisdom is well appreciated. I will try both solutions. It's almost as if you were right here looking at my gear. You should have a tech support hotline.

The cabinet I use is a Ampeg 610. Not quite an 810, but I'm a tiny guy, and convience is a must, especially while touring.

I used to use a very bass-boosted set-up, but I have since switched it up and focused on the mid-range. I will let you know how this turns out.

[Jimbobntnr]

Thanks for the advice Edge. Your sage-like wisdom is well appreciated. I will try both solutions. It's almost as if you were right here looking at my gear. You should have a tech support hotline.


agreed, what a great post, edge!

[edgebass5]

^^^I wrote that post while nursing a major hangover..... I'm suprised I could even type, let alone think :upset: