Double Bass Bass Max and DI Confusion

[acubass]

Hello, I am new to DB and have a question.

I have a K&K Bass Max and a radial passive DI box. When I go directly from the pickup to my LMII (1/4" input) the signal is pretty hot and sounds a little nasal.

When I place the DI between the pickup and the LMII using the XLR input the signal is nowhere near as hot, and not as nasal.

What is going on with the signal strenth here?


Thanks Much

 

[Francois Blais]

Forgive my ignorance, but what is a LMII?

That said, the passive Radial DI is just a transformer.
You certainly won't get a good match between this and a piezo pickup.
The input impedance is about 10K ohms, and you need about 1M ohms (1000K ohms).
The passive DI is loading the pickup.

 

[fleabee]

Little Mark II bass head

 

[acubass]

Forgive my ignorance, but what is a LMII?

That said, the passive Radial DI is just a transformer.
You certainly won't get a good match between this and a piezo pickup.
The input impedance is about 10K ohms, and you need about 1M ohms (1000K ohms).
The passive DI is loading the pickup.

So if I go to a gig without an amp will I have issues if the sound guy plugs me into the PA via a DI due to the bad match between a piezo and a DI?

Sorry if this is so basic but i'm a noob.

 

[cavemusic]

So if I go to a gig without an amp will I have issues if the sound guy plugs me into the PA via a DI due to the bad match between a piezo and a DI?

Sorry if this is so basic but i'm a noob.

You are correct, this will not work very well. As Francois said above, you need to plug a piezo pickup into a high impedance input, like a Fishman B-II or a LRBaggs ParaAcoustic DI. I bought my own ParaAcoustic DI and I bring it with me to all my gigs. Usually the soundman doesn't have a problem with it, but I've encountered a few that don't understand this issue. Don't worry if you didn't know - some sound guys don't even get it . Some bass amps, like the Acoustic Image amps and some others, have high impedance inputs for that very reason. Taking the DI out of the amp will work in that case. The spec on the LMII says it has 500 kilo-ohm input, which is higher than some but it might not be good enough. The ParaAcoustic input impedance is 10 mega-ohms.

 

[Francois Blais]

The LMII's 500K input impedance should be okay with the Bass Max.
The tightness of the BM's fit into the bridge wing will affect its tone.
It must not be too tight nor too slack.
Play with it, reverse it to see if it helps.
You can try it in the other wing too. (on the treble side)

The strings are another factor.
New Spirocores will give a zingy tone.

Are the strings new?
What brand are they?

 

[acubass]

The LMII's 500K input impedance should be okay with the Bass Max.
The tightness of the BM's fit into the bridge wing will affect its tone.
It must not be too tight nor too slack.
Play with it, reverse it to see if it helps.
You can try it in the other wing too. (on the treble side)

The strings are another factor.
New Spirocores will give a zingy tone.

Are the strings new?
What brand are they?

The strings are relatively new. The are helicore hybrids. I like them pretty well. I found I like the pickup on the treble side.

I played on stage for the first time last night. I took my LMII and pluged directly into the 1/4 input then the sound man took the DI from the back of the head. I did not take a cab. A) b/c all I have is an ampeg 15 (which I can coax into sounding fine enough if the room is o.k.) and B) I didn't have room in the car for it.

I got through the hour or so I was on stage, I learned a few things. Overall a good first time. I need to practce more on intonation and I need to get the proper gear. I definetly need to bring my cab next time so I will be able to adjust my on-stage volume.