Double Bass Bix preamp before Acoustic Image combo

[Trivolis]

Hi all,
I recently bought the Bix preamp from Grace Design ,it was a real bargain at 250e so I couldn't resist. I want to run it before my AI combo (contra series I ) in the lo gain input of the amp . I tried using it in the effect return input but I'm missing some of the sweet lows of the AI preamp . Sound is fuller on the lo gain input.
So...1)I can hardly run the gain past 9-10 o clock on the Bix without clipping its preamp( green light turns red)...is that normal? I use a Realist Lifeline.
2)Where should I put the gain on the Bix, the gain on the Acoustic Image and the master on the Acoustic Image to get the best results?
Thanks a lot!

 

[Ric Vice]

What you're experiencing is precisely the reason, I use my Grace Designs Felix with MAS 1/8 powered speakers. Running a preamp into the preamp on the amp doesn't always go as planned.
So, you'll just have to experiment with all the inputs High, Low, and Effects to see which one will work the best. I'd try actually using the Bix as you're preamp plugging it into the effects return
while plugging the bass into the Bix's input. It's worth a shot. Just my take.

 

[Trivolis]

What you're experiencing is precisely the reason, I use my Grace Designs Felix with MAS 1/8 powered speakers. Running a preamp into the preamp on the amp doesn't always go as planned.
So, you'll just have to experiment with all the inputs High, Low, and Effects to see which one will work the best. I'd try actually using the Bix as you're preamp plugging it into the effects return
while plugging the bass into the Bix's input. It's worth a shot. Just my take.

Yes, I did try that...Nice mic-like sound, I think for gigging I could use the extra "oomph" and warmth the pre amp of the AI seems to add to the sound though...

 

[oren]

I run my Felix into the instrument input on my Markbass combo, using the “amp out” on the Felix. I run the gain on the Felix around 9 o’clock and the Amp out level at around noon. The gain on the Markbass is usually set around 8 o’clock and the Markbass master as loud as needed for the room, which is usually no higher than noon. I find the trick when using multiple gain stages is to keep them all pretty low so you’re not overloading the stages towards the end. And certainly the Grace gear is quiet enough that you don’t have to worry too much about noise in the chain.YMMV, of course.

 

[Trivolis]

I run my Felix into the instrument input on my Markbass combo, using the “amp out” on the Felix. I run the gain on the Felix around 9 o’clock and the Amp out level at around noon. The gain on the Markbass is usually set around 8 o’clock and the Markbass master as loud as needed for the room, which is usually no higher than noon. I find the trick when using multiple gain stages is to keep them all pretty low so you’re not overloading the stages towards the end. And certainly the Grace gear is quiet enough that you don’t have to worry too much about noise in the chain.YMMV, of course.

Thanks for the tips!

 

[Trivolis]

Also, I think there is a -10db pad on the lo gain input on the Contra...When I use the effect return input I think the signal is stronger but maybe the quality is higher through the lo gain input...

 

[LaFaro01]

As Ric mentioned before... use the Effects Return to plug in the Bix, so that you can use "only" the poweramp of the AI... two (or more) preamps in chain tend to use problems, noise and other "garbage"... amplifying my Felix with my Eden Time Traveler I used the Effects Return, but just like Ric I switched to GS Sumo Power amplifier to follow the Felix...

 

[bassically_eli]

What is it that the Bix offers that the AI doesn't? AI designs amps specifically for DB. I can see how the footswitches on the Bix could be useful, but having only a two band EQ in your chain would be very limiting.

 

[Trivolis]

What is it that the Bix offers that the AI doesn't? AI designs amps specifically for DB. I can see how the footswitches on the Bix could be useful, but having only a two band EQ in your chain would be very limiting.

It offers very musical and natural high frequencies which my older Contra model seems to be lacking. In general it makes the sound more clear and musical ,if that makes sense.

 

[Wasnex]

As described, I would assume the problem is the Bix's output level. The spec sheet lists +22dBu as the max output. This is a very hot line level signal. So it makes sense that you have to keep the Bix turned down. AFAIK AI does not list the Max input level, but I would be surprised if they can take +22dBu. As long as it sounds good and signal to noise ratio is acceptable, don't worry about the gain controls being lower than you expect.

AI is at Series IV for their amps. I went through the owners manuals and did not see a "low gain" input. Series II had inputs labeled Low-Z and High-Z, but no pad.

On models that do have a "-10dB pad," it appears to only effects the mic input.

Maybe I missed something?

I suggest finding your manual and double checking the terminology and function of the amp's controls and inputs. Also take a look at the block diagram of the signal flow.

 

[Trivolis]

As described, I would assume the problem is the Bix's output level. The spec sheet lists +22dBu as the max output. This is a very hot line level signal. So it makes sense that you have to keep the Bix turned down. AFAIK AI does not list the Max input level, but I would be surprised if they can take +22dBu. As long as it sounds good and signal to noise ratio is acceptable, don't worry about the gain controls being lower than you expect.

AI is at Series IV for their amps. I went through the owners manuals and did not see a "low gain" input. Series II had inputs labeled Low-Z and High-Z, but no pad.

On models that do have a "-10dB pad," it appears to only effects the mic input.

Maybe I missed something?

I suggest finding your manual and double checking the terminology and function of the amp's controls and inputs. Also take a look at the block diagram of the signal flow.

Rick Jones sent me the manual for a model, similar to mine ,it says: Low Gain input 1MOhm , 8db lower gain.
Thanks for your helpful reply!

 

[Trivolis]

This is the set up: