ohms and cabs and hellppp!

[mntngrown]

I did the search function honest! Anyway I just bought an Avatar neo 1x12 @4ohm for quieter jams/gigs to go with my MB LMII, but I have the neo 2x12@4ohm for more volume. I understand I will need a 2 ohm amp to ever run them together when looking for a little more volume. I don't have a back up amp anymore. Should I get a cheap backup and a Y splitter and run the bass into 2 amps, get a used firebass etc for 2 ohm capability as a backup, or is there a better idea? Uptrade my LMII to a Genz capable of 2 ohms? I don't ever want to have another SKB case with heavy power amp etc. Or is it even stupid to try to run 1x12 and 2x12 from the same amp unless 2 channels?

 

[B-string]

Get the "cheap" backup amp and drive it from the effects send of the LMII to the second amps effect return. That way you keep the goodness (is that a word?) of your MarkBass's preamp and use the second amp's power amp only.

 

[mntngrown]

Thanks!

 

[tom once dead]

may I suggest the marshall MB series for a cheap head, or if you want power the Kustom 1200H.

 

[JimmyM]

Let's face it...an LMII into a 212 will be plenty for the vast majority of gigs you're probably doing. I'd just use it for the bigger ones, and use the 112 for the smaller ones. No need to go through pains stringing them together IMHO...you simply don't need it.

 

[stoneboy26]

Totally agree with JimmyM. I used my LMII in a band situation for the first time on Tuesday. 2 guitars, drums and keys, plus me, the LMII and a Schroeder 1212L. I didn't get the LMII above 9 oclock, and I probably should've been wearing earplugs!!!! Very very happy!!!

 

[Rip Van Dan]

I did the search function honest! Anyway I just bought an Avatar neo 1x12 @4ohm for quieter jams/gigs to go with my MB LMII, but I have the neo 2x12@4ohm for more volume. I understand I will need a 2 ohm amp to ever run them together when looking for a little more volume. I don't have a back up amp anymore. Should I get a cheap backup and a Y splitter and run the bass into 2 amps, get a used firebass etc for 2 ohm capability as a backup, or is there a better idea? Uptrade my LMII to a Genz capable of 2 ohms? I don't ever want to have another SKB case with heavy power amp etc. Or is it even stupid to try to run 1x12 and 2x12 from the same amp unless 2 channels?

If you think you might want to go to the cheap back-up amp, most amps will let you run a signal out from the effects out of an effects loop (which is post eq siognal) to the effects in of the effects loop of another amp.

This feeds the preamp signal from your "master" amp, into a cheap slave amp by-passing that slave amps EQ entirely. So you're feeding the eq'd signal from your master amp directly into the power section of the slave amp. Once you balance the volumes on the two amps, you should be able to control the volume of the set by just turning the master on the main amp. If not, you'll have to mess with volume controls on both heads.

Plug one cabinet into the master and one cabinet into the slave and away you go. Good news is that the sound coming out the slave will be the sound eq you set up in the master.

I had to do this when I had a 4 ohm and an 8 ohm cab and the amp's minimum was 4 ohms. I had another GK head that was limited to a minimum of 8 ohms, so I plugged my 8-ohm 115 cab into that and my 4 ohm 212 cab into my Nemesis using the method I just described and it worked great. Neither amp got hot and I controlled all the eq and volume from my nemesis.

Have since bought another 8 ohm cab and just run both out of my Nemy now, but there are options.

Dan

 

[Bassorama57]

Let's face it...an LMII into a 212 will be plenty for the vast majority of gigs you're probably doing. I'd just use it for the bigger ones, and use the 112 for the smaller ones. No need to go through pains stringing them together IMHO...you simply don't need it.

+1 LMII into the Avatar 2x12 at EIGHT ohms is plenty loud; at FOUR ohms? If that ain't gettin' er' done...it's back to the massive roadready case and a few 8x10 or 4x12 stacks for you!

 

[RickenBoogie]

Let's face it...an LMII into a 212 will be plenty for the vast majority of gigs you're probably doing. I'd just use it for the bigger ones, and use the 112 for the smaller ones. No need to go through pains stringing them together IMHO...you simply don't need it.

And another big +1. You've got a great amp now, (well, I' don't care for it, but...), and 2 different speaker box set ups, one big, one small. Unless you're worried about your amp crapping out during a gig, you need nothing. Even if you did get a back-up amp, it could still be a 4 ohm head. Unless you're just hell bent on running 3 12's together, well I could understand that too.

 

[BassmanPaul]

The problem I see is that the single 12 @ 4Ω in parallel with a twin 12 also @ 4Ω are both going to divide the power between themselves equally. Let's say you give them 200W, the single 12 will get 100W while the 12s in the twin will get 50W each!

Paul

 

[mntngrown]

Thanks for all the input guys! Yeah once in a rare while outdoor with no PA support maybe, OK, so I just have a power fetish. I'm always worried about blowing speakers. Needless worry seems to be the consensus here though.

 

[the_hook]

If you think you might want to go to the cheap back-up amp, most amps will let you run a signal out from the effects out of an effects loop (which is post eq siognal) to the effects in of the effects loop of another amp.

This feeds the preamp signal from your "master" amp, into a cheap slave amp by-passing that slave amps EQ entirely. So you're feeding the eq'd signal from your master amp directly into the power section of the slave amp. Once you balance the volumes on the two amps, you should be able to control the volume of the set by just turning the master on the main amp. If not, you'll have to mess with volume controls on both heads.

Plug one cabinet into the master and one cabinet into the slave and away you go. Good news is that the sound coming out the slave will be the sound eq you set up in the master.

I had to do this when I had a 4 ohm and an 8 ohm cab and the amp's minimum was 4 ohms. I had another GK head that was limited to a minimum of 8 ohms, so I plugged my 8-ohm 115 cab into that and my 4 ohm 212 cab into my Nemesis using the method I just described and it worked great. Neither amp got hot and I controlled all the eq and volume from my nemesis.

Have since bought another 8 ohm cab and just run both out of my Nemy now, but there are options.

Dan

I'm in a similar situation, but mine was borne out of being too new at this and finding (what I thought was) some excellent opportunities.

I bought a Bag End 2x10 (400w @ 4 ohms) and was running that nicely with an Acoustic B200H (200w @ 4 ohms). But then a local sale came up for a Bag End 1x18. I brought my 2x10 and bass to test it out and the guy had a few different amps and was able to run the 2x10 and 18 together. The sound was really good, and the price for the 18 was too good to pass up.

So then the quest began on how to pair the 2 mismatched cabs with 1 amp.

From the info I've garnered if you use a 2 ohm capable amp the 2x10 will draw more power then the 18, and may sound louder. If you get a 2 channel amp you should be ok, but do I really want to go that route?

One thought is to find a 1x12 at 8 ohms to pair with the 18, but is that even a good configuration? Does the 1x12 need a tweeter to get the mid-highs and let the 18 handle the lows?

I'm just weighing out options (of which one would be to just sell the whole thing and start over...).

 

[RedLeg]

The problem I see is that the single 12 @ 4Ω in parallel with a twin 12 also @ 4Ω are both going to divide the power between themselves equally. Let's say you give them 200W, the single 12 will get 100W while the 12s in the twin will get 50W each!

Paul

i dont think it is the speakers you need to be worried about there. it is the massive stroke the LMII will have being ran @ 2 ohms

 

[Jaco who?]

From the info I've garnered if you use a 2 ohm capable amp the 2x10 will draw more power then the 18, and may sound louder. If you get a 2 channel amp you should be ok, but do I really want to go that route?

Actually, with a 2 ohm capable head and a 4 ohm cab with 2 speakers and an 8 ohm cab with 1 speaker you have ideal power distribution. Think about it a little bit: Say you have 600 watts divided 2/3rds into the 2x10 cab and 1/3 into the 1x18 cab - each speaker in the 2x10 gets 200 watts and the 18" gets 200 watts too.

It gets much trickier when you have equal impedances combined with cabs with different numbers of speakers, (like BP talked about).

 

[eaglemachine]

another option would be to buy a cheap power amp. You might could find one of those cheaper than a bass amp and it is usually more wattage...

 

[the_hook]

another option would be to buy a cheap power amp. You might could find one of those cheaper than a bass amp and it is usually more wattage...

Thanks for the info. Several options seem to be available;

1) If what Jaco who? says is true then it opens up the option of getting a 2 ohm capable head without worring about the 2x10 hogging more power than the 18. In that case I'd be able to look at the new Acoustic B600H (I have the B200H) which does handle up to 600w @ 2 ohms

2) Use my current B200H amp to power one cab, connected thru my Sansamp DI pedal into a QSC RMX850 dual channel power amp into another cab. Which amp should effectively power which cab?

2) Use the B200H amp as only an EQ into a Y connector (or a X-over) into a QSC amp into the 2 cabs (or do I even need the Y connector and go straight from the B200H to QSC to the 2 cabs?)

3) get a QSC amp and bass pre-amp (like a Tech 21 SansAmp RPM Preamp/Bass Driver)

4) get a tube amp that can handle 2 ohms like the Traynor YBA-200...which the response now from the YBA thread doesn't seem like such a good option as the watts will drop quite noticably...

 

[eaglemachine]

Thanks for the info. Several options seem to be available;

1) If what Jaco who? says is true then it opens up the option of getting a 2 ohm capable head without worring about the 2x10 hogging more power than the 18. In that case I'd be able to look at the new Acoustic B600H (I have the B200H) which does handle up to 600w @ 2 ohms

2) Use my current B200H amp to power one cab, connected thru my Sansamp DI pedal into a QSC RMX850 dual channel power amp into another cab. Which amp should effectively power which cab?

2) Use the B200H amp as only an EQ into a Y connector (or a X-over) into a QSC amp into the 2 cabs (or do I even need the Y connector and go straight from the B200H to QSC to the 2 cabs?)

3) get a QSC amp and bass pre-amp (like a Tech 21 SansAmp RPM Preamp/Bass Driver)

4) get a tube amp that can handle 2 ohms like the Traynor YBA-200...which the response now from the YBA thread doesn't seem like such a good option as the watts will drop quite noticably...

Or keep your current amp, run one cab off of that, go line out out of that head into a poweramp and run your other cabinet....

 

[the_hook]

Or keep your current amp, run one cab off of that, go line out out of that head into a poweramp and run your other cabinet....

Which cab should the head feed and which one the power amp?

I just thought of another option; don't use the B200H amp, just plug the Sansamp pedal into the QSC which has 2 channels and feeds both cabs separately. Problem is I haven't found too many settings on the pedal I like (vs the Acoustic EQ).

But that might be because it's linked thru the amp head too, whereas this way it would be the pedal direct into the amp.

 

[the_hook]

Little confused here; would I be able to use the Acoustic B200H thru a QSC into the 2 cabs? If I can, how would I connect the two (which input/output on the B200H)?

Or do I have to use a dedicated pre-amp into the QSC? Would the Sansamp DI pedal work?