Titan 48 for 12v build// No Labs in the UK

[Seth]

You're absolutely correct, power in always equals power out. Since the two scenarios both result in 450 watts of power, the 12V power the amplifier requires in either case would be 450 watts plus an (in)efficiency percentage. That number divided by 12 volts gives you the amperage the amplifier will potentially draw from the battery/alternator. (roughly)

[Bruce Weldy]

My vote is to use a really, really long extension cord.

[Grant Bunter]

Since the two scenarios both result in 450 watts of power, the 12V power the amplifier requires in either case would be 450 watts plus an (in)efficiency percentage. That number divided by 12 volts gives you the amperage the amplifier will potentially draw from the battery/alternator. (roughly)

Are you sure about this? I only ask, because, I'm not.
The only consistent figure I can see is 450W.
Are you telling me that impedance doesn't matter and has no bearing in the calculation or the resultant requirements of the power supply
And likewise with amperes even though amperes in both scenarios are also different?
Because the above doesn't seem to acknowledge that 450W is a product of 2 different calculations.
It's like, by sheer fortune, because the 2 scenarios actually arrive at the same calculation, the amp will respond to both scenarios in exactly the same way...

[Seth]

Since the two scenarios both result in 450 watts of power, the 12V power the amplifier requires in either case would be 450 watts plus an (in)efficiency percentage. That number divided by 12 volts gives you the amperage the amplifier will potentially draw from the battery/alternator. (roughly)

Are you sure about this? I only ask, because, I'm not.

100% sure on the calculation. One could certainly get more specific with the numbers used.

The only consistent figure I can see is 450W.
Are you telling me that impedance doesn't matter and has no bearing in the calculation or the resultant requirements of the power supply

A little distinction is needed here, "power supply" could mean a couple different things in this discussion. There's "power supply" that could be a battery or a plug on the wall, and there's "power supply" that is a portion of the circuitry that creates rail voltage in an amplifier.

Assuming you're talking about battery/wall power supply, if we're wanting to identify how many amperes an amplifier will draw, all that matters is the load in watts, the amplifiers efficiency, and the voltage of the battery/wall power. Obviously, the driver's impedance will dictate what the load will be. So, it is part of the overall equation.

And likewise with amperes even though amperes in both scenarios are also different?
Because the above doesn't seem to acknowledge that 450W is a product of 2 different calculations.

Amplifier output could be 32V into 1Ω or 126V into 16Ω, either is 1000 watts and we need to draw 1000 watts from our battery/wall power supply to make it. How many amperes the amplifier will draw from the battery/wall power supply depends on the battery/wall power supply voltage.

It's like, by sheer fortune, because the 2 scenarios actually arrive at the same calculation, the amp will respond to both scenarios in exactly the same way...

In this scenario it would be two different amplifiers, but yes they would essentially draw the same amperage from the battery.

[Seth]

Grant, I've been thinking about this and it won't leave my mind... I highly value the vulnerability and humility you expressed in your last post. I admire you for that. And, at whatever level it may be, I genuinely value you as a friend.

[Grant Bunter]

Grant, I've been thinking about this and it won't leave my mind... I highly value the vulnerability and humility you expressed in your last post. I admire you for that. And, at whatever level it may be, I genuinely value you as a friend.

Thanks Seth.

Just to clarify, my reference to power supply is what supplies the voltage rails of the amplifier, not the source supply draw.

And to make matters worse for me lol, there's nominal cab impedance (which is how 450W has been calculated), then there's the fact that impedance varies with frequency.

Apologies to the OP. Welcome to world of exploring things which are at best, seemingly relevant.
Or have nothing to do with the topic at hand, depending on your viewpoint...

[Seth]

Grant, I've been thinking about this and it won't leave my mind... I highly value the vulnerability and humility you expressed in your last post. I admire you for that. And, at whatever level it may be, I genuinely value you as a friend.

Thanks Seth.

Just to clarify, my reference to power supply is what supplies the voltage rails of the amplifier, not the source supply draw.

I know just about enough about amplifier circuitry and design to appear knowledgeable to someone who knows nothing, but would appear technically illiterate to someone who is a Circuit Design Engineer. I'd love to discuss it more sometime. However, I agree with you, the specifics may be a little too stray and not particularly pertinent to this thread.

And to make matters worse for me lol, there's nominal cab impedance (which is how 450W has been calculated), then there's the fact that impedance varies with frequency.

The simple calculation is based on mean figures. One could certainly get more specific with the conditions if more specific information is needed.

Apologies to the OP. Welcome to world of exploring things which are at best, seemingly relevant.
Or have nothing to do with the topic at hand, depending on your viewpoint...

Given the context of the project, I feel it has valuable relevance. But, Kairos, if you found this distinction and side conversation unhelpful, I apologize too.

[Mishkin]

Ive been away from the computer for a bit, but Actually thank you both! In these disagreements and resulting discussion I think i can learn alot!
But Im also glad it seems all parties are at peace.

At this point , Im going to order the Fountek drivers and give Seths 2x12 solution a go. Will let you all know how it goes. Thanks Seth, for your interest and work towards this goal.

I have access to a mates workshop again beginning of July so will build the cab then - the panel blanks are already cut.

Seth, After your prior comment on wiring I was thinking a four pole speakon socket that connects the 12s in series and has a pass through to a second speakon socket . (for a potential future of being used with a mains power supplied amp, coupled with a 2nd Titan cab)

AS WELL as ; a conventional 2 pole terminal plate that connects to the 12s in parallel for the standard speaker cable coming fromthe 12v amp.

sound right ?

[Seth]

Seth, After your prior comment on wiring I was thinking a four pole speakon socket that connects the 12s in series and has a pass through to a second speakon socket . (for a potential future of being used with a mains power supplied amp, coupled with a 2nd Titan cab)

AS WELL as ; a conventional 2 pole terminal plate that connects to the 12s in parallel for the standard speaker cable coming fromthe 12v amp.

sound right ?

Unfortunately, the wire combinations will create shorts having two jacks wired that way.

There are a few ways to do it though. If it were mine, I think I'd opt for a DPDT switch. Sorry about the horrible diagram quality.

However, the safest way to do it, so there are no mistakes (oops the switch was in the wrong position and the smell of hot electronics fills the air) is to have it be an actual wiring change behind the jack plate.

Here's how to wire the DPDT switch option.

Screenshot (261).png (10.84 KiB) Viewed 4768 times

[Mishkin]

Thanks again seth,

I've beeen wondering if theres anyway to do this dpdt switch option, or something like it, but in co-ordination with two sockets? So as to make it a little less likely fry things because the switch got knocked the wrong way (you'd have to flip the switch wrong and plug into the wrong socket to run it at the wrong impedance).

Could that work somehow?

[Seth]

Thanks again seth,

I've beeen wondering if theres anyway to do this dpdt switch option, or something like it, but in co-ordination with two sockets? So as to make it a little less likely fry things because the switch got knocked the wrong way (you'd have to flip the switch wrong and plug into the wrong socket to run it at the wrong impedance).

Could that work somehow?

No problem Kairos

I think you could achieve that with a 4PDT switch. But, my brain's a little spent on other projects to create a wiring scheme at the moment. I'll get back to you on that.

There's another really simple and safe option though... Use a single 4 pole SpeakOn jack in the cab and make two separate speaker cables, one for 8Ω one for 2Ω, and just do the parallel or series wiring within the SpeakOn connector itself. Keep one cable always attached to your 12v system and the other cable with your mains powered amplifier. That way, wherever you plug the cab in, it'll automatically be wired correctly.


How's the project progressing, BTW?

[Seth]

[Mishkin]

There's another really simple and safe option though... Use a single 4 pole SpeakOn jack in the cab and make two separate speaker cables, one for 8Ω one for 2Ω, and just do the parallel or series wiring within the SpeakOn connector itself. Keep one cable always attached to your 12v system and the other cable with your mains powered amplifier. That way, wherever you plug the cab in, it'll automatically be wired correctly.


How's the project progressing, BTW?

thats a much more elegant solution

But If i've understood right - that would mean no potential to pass through to the next titan cab? as youve used terminals 3 and 4 on the speakon socket with the alternate wiring option, Is that right ?

Sadly the project has been stalled a bit, the drivers and dsp were coming from france and since brexit and the UK leaving the european union that now requires taxes and customs paid, the processing isn't efficient yet as this is all relatively new so the parts have been held ransom by this international bureaucracy fail

will update as soon as i can get building, im very itchy to make this happen .

Hope your evening is going well.

[Seth]

But If i've understood right - that would mean no potential to pass through to the next titan cab? as youve used terminals 3 and 4 on the speakon socket with the alternate wiring option, Is that right ?

That is correct that pass through within the cab would not be possible. However, you could very easily wire in a female SpeakOn pigtail at the speaker end of the the speaker cable to pass the signal on to another cab.

[Mishkin]

Hi all.

Ive been on an unintended break from working on this project. A long postal saga- resulting in delays getting the drivers, as well as being away from home for work.

I'm now finally home, Have the pair of Fountek 12s that Seth found, a 12v dsp and hoping to get this going.

i dont have access to a workshop anymore but have borrowed some tools and clamps and doing the best i can with building in a my little flat garden

Questions at this stage ;

These 2 12s are heavy ! 15kg together ( 32Ibs ). I went for anchors with retention blocks and lined up insert nuts to carry that weight with allen key bolts rather than screws . As you can see im about to do the braces around the baffle, the small flange to baffle braces and the anchor to panel 3 brace. Theres not that much wood left in that 29" wide baffle after cutting out for the drivers, with this much weight on there do people think i should add some more braces, or will those mentioned in the plan be enough?

Another thought, for the internal cabling of your subs do people tend to use tour grade van damme type cable (like you would use for the speakon leads, with a extra flexible circular sheathing) or just normal old fashion 2.5mm multi strand speaker cable? I was about to use some normal old 2.5mm, then suddenly had the horrible thought of sealing it in there and hating myself for it when it somehow fails in a couple of years. what do you guys use?

All the best ,
and i'm happy to be back here thinking about all this again,

Kairos