Help: running two cabs when there aren't enough sockets......?

[Beedster]

Folks, I've taken my Ashdown Drophead to rehearsal (usually take Mesa M-Pulse), there are three O/Ps on amp, 4/8/16 ohms, but only I/Ps on two 8ohm cabs. Can I run both cabs from different ohm outputs? 
 

 

 

Edited 12 hours ago by Beedster

[Hellzero]

Absolutely not, Chris, if it's a tubes (valves) head, which it seems to be.

[Beedster]

44 minutes ago, Hellzero said:

Absolutely not, Chris, if it's a tubes (valves) head, which it seems to be.

I thought not thanks Tony 🙏

[NancyJohnson]

Moving forward, could you drill out a second jack socket (or make up a replacement plate) to allow the cabs to be daisychained?  This will give you the option of going out of the 4ohm output.

 

Alternatively (and I don't know whether this would work), output the 4ohm to an ABY box and squirt the signal to both cabs in parallel?

 

(If the ABY option is doable - I'm sure someone will know - I have a Vein Tap Separator mini I can send up.)

[Beedster]

4 minutes ago, NancyJohnson said:

Moving forward, could you drill out a second jack socket (or make up a replacement plate) to allow the cabs to be daisychained?  This will give you the option of going out of the 4ohm output.

 

Alternatively (and I don't know whether this would work), output the 4ohm to an ABY box and squirt the signal to both cabs in parallel?

 

(If the ABY option is doable - I'm sure someone will know - I have a Vein Tap Separator mini I can send up.)

 

Many thanks @NancyJohnson, I felt a right idiot, I usually run the two cabs from my Mesa head but thought I 'd try them out with the Ashdown Drophead 200, seems I stumbled across a rare combination of an amp that only has a single speaker out (or at least while there are three options only one can be used at a time), and two cabs that can't be daisychained! Something tells me that the life expectancy of a standard ABY box would be rather short coming after the amp, I might be wrong, and if so I'm guessing there's probably a commercially available post-amp signal splitter? Many thanks for the offer of the Separator, it would be good to know fropm other on here whether or not that's going to work 🙏    

[itu]

If you cannot lock the cables to that Y-splitter + inputs + output, I see a transformer failure in the near future. Will cost a lot.

 

I hate 1/4" plugs in tube (valve) world. Speakon is a secure option.

[Beedster]

2 minutes ago, itu said:

If you cannot lock the cables to that Y-splitter + inputs + output, I see a transformer failure in the near future. Will cost a lot.

 

I hate 1/4" plugs in tube (valve) world. Speakon is a secure option.

 

Thanks @itu,  don't panic, I'm using the amp wisely! I messaged last night as I was wondering whether it might be safe to run from two of the three outputs but I was assuming not and am not inclined to experimentation with electrics. The two cabs are to all intents the top and bottom halves of a Mesa 1516 (the top cab having 1 x 10, 2 x 6 and a tweeter) so to get the best out of the rig I was thinking about bi-amping at the next rehearsal anyway, driving the 15 with the Mesa and the 10/6/6 with the Ashdown, probably safer and more satisfactory all round 👍 

[Beedster]

13 minutes ago, itu said:

I hate 1/4" plugs in tube (valve) world. Speakon is a secure option.

 

Agreed, especially when they're configured as in the first post above in which it would be all too easy to simply plug two in, a single socket with switching between loads seems a far safer bet?  

[NancyJohnson]

2 hours ago, Beedster said:

 

Many thanks @NancyJohnson, I felt a right idiot, I usually run the two cabs from my Mesa head but thought I 'd try them out with the Ashdown Drophead 200, seems I stumbled across a rare combination of an amp that only has a single speaker out (or at least while there are three options only one can be used at a time), and two cabs that can't be daisychained! Something tells me that the life expectancy of a standard ABY box would be rather short coming after the amp, I might be wrong, and if so I'm guessing there's probably a commercially available post-amp signal splitter? Many thanks for the offer of the Separator, it would be good to know fropm other on here whether or not that's going to work 🙏    

I am curious about the ABY scenario.

 

If you're running a single out (at 4ohms) into an ABY with both outputs open and then into a pair of 8ohm cabinets, would the load be recognised as 4ohms? 

[Beedster]

10 minutes ago, NancyJohnson said:

I am curious about the ABY scenario.

 

If you're running a single out (at 4ohms) into an ABY with both outputs open and then into a pair of 8ohm cabinets, would the load be recognised as 4ohms? 

 

I think so, but I'm not sure a box designed for instrument level would survive being placed after the amp....?

[pete.young]

6 minutes ago, Beedster said:

 

I think so, but I'm not sure a box designed for instrument level would survive being placed after the amp....?

 

I'd expect it to be fried in fairly short order. A cab splitter box, like this one from Palmer: https://www.palmer-germany.com/en/products/signal-splitter-switcher/5088/cab-m would be the way to go, or a DIY version.

 

[Beedster]

1 minute ago, pete.young said:

 

I'd expect it to be fried in fairly short order. A cab splitter box, like this one from Palmer: https://www.palmer-germany.com/en/products/signal-splitter-switcher/5088/cab-m would be the way to go, or a DIY version.

 

Thanks Pete, funny I was looking for something that would do that but not knowing whet they're called didn't find it! I'll order one of those, Anderton's have them in stock 👍

[Beedster]

So, another question......

 

As the cab splitter allows me to run parallel at 4ohms or series at 16ohms, would I expect any difference in volume/tone or is it to keep all things equal in this respect that the Drophead has separate outputs for each (4/8/16ohms). Only asking out of curiosity really, I imagine i'll be running them in parallel at 4ohms but always good to know the options 👍 

[obbm]

Back in the day I used to make boxes that allowed either series or parallel speakers but with combo Speakon. That Palmer box looks to be just the job.

 

[Lozz196]

1 minute ago, obbm said:

Back in the day I used to make boxes that allowed either series or parallel speakers but with combo Speakon. That Palmer box looks to be just the job.

 

I remember buying one of those from you way back

[Woodinblack]

32 minutes ago, NancyJohnson said:

I am curious about the ABY scenario.

 

If you're running a single out (at 4ohms) into an ABY with both outputs open and then into a pair of 8ohm cabinets, would the load be recognised as 4ohms? 

 

Yes it would, but the problem with that is a) the ABY might have signal level rather than speaker level wires, but maybe not, there isn't much in one after all, and B) they are designed to switch, which means if you accidently trod on it and switched the output off so it wasn't connected, you would present an open output to the valve amp and things inside would get pretty hairy quite quickly. Ultimately if this is a scenario that you envision happening a lot, just take the ABY box, and bypass the swich so it is always connected.

[Beedster]

15 minutes ago, obbm said:

Back in the day I used to make boxes that allowed either series or parallel speakers but with combo Speakon. That Palmer box looks to be just the job.

 

 

I'd be far happier if that cab splitter box was Speakon..... 🤔

[Woodinblack]

13 minutes ago, Beedster said:

 

I'd be far happier if that cab splitter box was Speakon..... 🤔

 

get a metal box, two speakon circuits, a jack socket and a bit wire, join them together in a box and job is done!

Although it doesn't help if the speaker has a jack socket too. Other option, replace that plate with one with two speakon sockets.

[Beedster]

18 minutes ago, Woodinblack said:

 

get a metal box, two speakon circuits, a jack socket and a bit wire, join them together in a box and job is done!

Although it doesn't help if the speaker has a jack socket too. Other option, replace that plate with one with two speakon sockets.

 

That's a good plan 🙏

[itu]

@Woodinblack had the best solution. I would continue with a similar modification to the speakers, too. Speakon is much more reliable solution than a plug.

 

Before using the modified set, and while the units are open, I would check all connections from the head to the speakers with the cables connected. DMM with beeper is a valuable tool.

[chris_b]

Use a second amp for the second cab and daisy-chain the amps.

[Hellzero]

2 hours ago, Woodinblack said:

 

get a metal box, two speakon circuits, a jack socket and a bit wire, join them together in a box and job is done!

Although it doesn't help if the speaker has a jack socket too. Other option, replace that plate with one with two speakon sockets.

Or use the Neutrik Speakon/Jack combo named NLJ2MDXX-H. 😉

[nekomatic]

3 hours ago, Beedster said:

So, another question......

 

As the cab splitter allows me to run parallel at 4ohms or series at 16ohms, would I expect any difference in volume/tone or is it to keep all things equal in this respect that the Drophead has separate outputs for each (4/8/16ohms). Only asking out of curiosity really, I imagine i'll be running them in parallel at 4ohms but always good to know the options 👍 

If the cabs aren’t identical you don’t want to run them in series. 

[Beedster]

17 minutes ago, nekomatic said:

If the cabs aren’t identical you don’t want to run them in series. 

 

Thanks, not doubting your word but I'd be interesting in understanding why?

[itu]

Power will be spread to the cabinets the way the impedance behaves (impedance is not constant). Also the frequency response may be strange. But the best way to understand the behaviour is to test the set.