Pre-amp & power amp adjustments

[StephenR]

Jazzy, surprised you are having issues with the Barefaced cabs farting out and also surprised you are having trouble getting enough volume. I have a Super Twin here and am waiting for a Big Baby 2 to arrive, the Super Twin by itself is extremely loud with my Crest ProLite 3.0 and I have been able to dial in a huge amount of low end. When I did research on the cabs the consensus is that they are difficult or impossible to get to "fart out" on the low frequencies. I suspect distortion is coming from your signal chain. The preamp in the Series basses has enough gain to drive a power amp by itself if cranked fully up so maybe try backing off on the gain there to start. I seem to remember you just got a new power amp. Do you still have the old one and if so have you tried using that instead to see if it may be a gain matching problem between your pre and the new power amp?  FWIW... I believe I have the gain set a little over half way on my Series bass.

[jazzyvee]

I can get volume but not clean volume but I gather from what you are saying generally is that I need to experiment with a lower output from the bass. I do recall JJ mentioning in a thread here that the series basses are at or virtually line level but for JJ who normally goes DI and uses a stage monitor and not a bass rig there is less likelyhood of him overdriving anything.  A couple of my band members have rehearsal studios so I will try to get a long afternoon in there and set my rigs up and try a few things like lowering the output levels on my basses and recording things so I can listen back objectively. I too was surprised to hear any distortion from the BF cabs as like you I did a lot of reading and asked a lot of questions when I called the BF office to discuss my needs before purchase. As it happens the first few gigs I did with the Big Twin II was jazz funk in venues with great acoustics so I didn't need much volume and the other was a large venue, big stage with Pro FOH and stage crews so I didn't need loud. But when I started doing venues that were less like those two I started to hear the cabs getting noisy.
I think first off will be adjusting the trim pots of my basses down to about 2/3rds and see what goes on. Then may be try the bass direct into the Power amp and see if that works and is clean.

[jazzyvee]

@joe, I sold the QSC PLX amp far to quickly as I wanted to get rid of that heavy lump that was preventing me using my best rig regularly for years. The downside is that to my ears, it is a far better sounding amp than the Crown XLS1502 that I now use. Hard to describe but it seems to have a thicker more dense sound and much more punchyand detailed bottom end yet the lighter touch is pristine. In hindsight I think maybe I should have kept the QSC and joined a gym!

Anyway the Crown is still a good amp no taking away from that.  I will back off my gains, (ha, predictive text put brains in first maybe it's on to something), like you guys are suggesting and see how that works out. I have a gig in a few weeks so that should give me a chance to try things live.

[smokin_dave]

Hey jazzy.On the Crown try setting the input sensitivity to ".775V-HIGH" in the menu.This may help.

[jazzyvee]

Cool, thanks Dave

[jazzyvee]

As for the gain trim pots is there any difference between setting the trim pots lower or just reducing the pickup volumes on the front of the bass? Bassically just turn the bass volume down?

[tx196059]

Good question Jazzy. And to expand on that, what are the differences between the pickup volume(s) on the front of the bass, between the Series and non Series circuits? Are the Series controls analog, and non Series digital?

[jazzyvee]

As far as ny knowledge of alembic its all analogue.

[rv_bass]

If you are using your F-1X, try using input 2, it pads by 6dB.

http://www.alembic.com/support/F-1Xoperatingguide.pdf

[edwardofhuncote]

If you are using your F-1X, try using input 2, it pads by 6dB.

http://www.alembic.com/support/F-1Xoperatingguide.pdf

^That^


I discovered, for whatever reason, the output of my Custom fretless bass is considerably hotter than that of my Persuader 5-string, which is a little odd since I believe they have the same preamp. (I put the new pan module upgrade in the Persuader a while back...) Granted, I never have messed with the gain trimpots on the Custom, only the Persuader, and only then to balance the disparity between the P and J pickups. The output on "Chain-Links" is just scorching... I probably could overdrive something if I tried.

[JimmyJ]

Jazzy, on Series basses the output level trim pots really work the same as the front panel volume controls.  Think of it like setting your max output for whatever your chain of gear is.  Then if you run into a situation where you need to play into a piece of gear that can't take that much level, you can either change the trim pots or just turn down your master or p/u volumes until the gear is happy.  Because of our active electronics and lo-z outputs there is no change in the tone as you turn the instrument down.  On passive instruments the load changes with the volume so that also effects the frequency response.

I run my basses with a very hot output level into a REDDI, which even adds a bit more gain.  The result is close to +4 line level.  But if I run into a situation where somebody wants to go into a different preamp after my DI then I'll trim the master volume down for a more "normal" output level.  I've gone as far as inlaying marks for the two different situations.   

Jimmy J