HELP: Shuttle 6.0 cabinet configuration/cutting out issue.

[anais]

Hey everyone,

New here, not a bassist at all but my bassist is having some issues with his rig and I figured I would throw it out there.

His rig: Tune Technologies TWX with active electronics into a Shuttle 6.0 running 2 8 ohm cabs in Parallel (Glockenklang 2x12 and a hughes and kettner 1x18).

This cutting out issue happened maybe once or twice when he runs just the 2x12, but for some reason when both cabinets are running the clip light engages more often and there are moments of cutting out.

I am a tube amp nerd.. the only solid state stuff I really have hands on experience with is an SSL console.. so my mentality with the approach to this problem is coming from a tube mind set. Might anyone have some input for me that could prevent this problem from happening in the future?

Thanks!

 

[KJung]

When you lower the impedance with a transistor amp like the Shuttle, the power output increases. If you really push an amp beyond its limits at its lowest recommended impedance (in the Shuttle's case, 4ohms), you might hit the safety shutdown circuitry. This should only happen if you are playing very loud with a significant amount of low bass dialed into your tone.

The Shuttle power amp 'clip' light is a rather unusual design that really doesn't indicate anything particularly useful (i.e., it indicates when the power amp limiting starts to kick in, and no action is required). So, if that light is coming on, best just to ignore it.

However, if the 'clip' light comes on and stays on early in the night, and the band's volume continues to climb, there is a possibility that he has reached the amp's limits, and eventually when pushed really hard, the amp might go into safety protection. Unfortunately, there is no indication of when you go from 'soft power amp limiting' to the 'danger zone of clipping', so again, it is best to just ignore that indicator and use your ears (again, if that output clip light comes on every once in a while, it is a zero issue).

If he has checked everything else out (making sure his cables are good, etc.), it sounds like he just needs more watts when really pushing the volume at 4ohms. This again is not 'Genz' specific, but rather 'pushing an amp beyond its limits at a low impedance.

If he has that 'bass boost' button engaged, that eats up a LOT of power and headroom. He should try reducing bass EQ a bit, which might solve the issue.

 

[hasbeen]

thanks for the assist KJ

 

[hasbeen]

Hey everyone,

New here, not a bassist at all but my bassist is having some issues with his rig and I figured I would throw it out there.

His rig: Tune Technologies TWX with active electronics into a Shuttle 6.0 running 2 8 ohm cabs in Parallel (Glockenklang 2x12 and a hughes and kettner 1x18).

This cutting out issue happened maybe once or twice when he runs just the 2x12, but for some reason when both cabinets are running the clip light engages more often and there are moments of cutting out.

I am a tube amp nerd.. the only solid state stuff I really have hands on experience with is an SSL console.. so my mentality with the approach to this problem is coming from a tube mind set. Might anyone have some input for me that could prevent this problem from happening in the future?

Thanks!

Please have your bassist call us at the shop: 480.941.0705. We can "talk" through it.

 

[KJung]

thanks for the assist KJ

 

[agedhorse]

Please have your bassist call us at the shop: 480.941.0705. We can "talk" through it.

Ask specifically for Scott on this.

Two things that I would recommend checking... the first is to be sure that the cabinets are really 8 ohms. We have seen a few instances where a cabinet has been repaired, or were incorrectly marked from the factory. The Shuttle has spophisticated protection circuitry to protect itself from such damage.

The second thing to try is bypassing the effects loop, or cycling the return jack to be sure the return signal's internal switch contacts are fully seated. This is a common problem in all brands of amp that use a series effects loop, and is also very common in pro audio consoles that use insert jacks on each channel. The vibration sitting on a caninet along with a bit of debris or dust on the contacts can cause this symptom as well. (this troubleshooting tip applies to all amps in general BTW)