Brahma 12D4 Question

[Phlipbak 10+ year member]

My friend has a 5 cubic foot TCAB tuned to 36hz with four 4" aeroports that he was going to put two Brahma 12's in. He knows they have a 600w RMS but he was wondering if he could run em with 1100 watts a piece and they be ok? I don't know what model but the amp is rockford and puts out 2176w x1 at one ohm.

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[T3mpest 10+ year member]

If he keeps the gains down he'll be fine. People ran 1000+ on the older ones no problem, the thermal power handling on the new ones is actually higher.

 

[Death By Bass 10+ year member]

If he keeps the gains down he'll be fine. People ran 1000+ on the older ones no problem, the thermal power handling on the new ones is actually higher.

no its not, its lower...

the old ones, were a 1600watt 3inch coil, the new ones are a 600watt 2.5inch coil I do believe //content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif

 

[newusername 10+ year member]

nthe old ones, were a 1600watt 3inch coil, the new ones are a 600watt 2.5inch coil I do believe //content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif

The new ones have a higher surface area:mass ratio than the older ones and thermal power handling has actually increased. If we were to take their current ratings and change them to the IEC method they used before, you would actually see that the rated power handling has increased.

Whether it can take 1kw+ depends on the enclosure; need to make sure you are not exceeding mechanical limits.

Neil

 

[DanWiggins 10+ year member]

That is 5 cubic feet for the pair, tuned to 36 Hz? Pretty peaky box... Try blocking one of the Aeroports to drop the tuning frequency to 30 Hz - I think he'll like the sound better and it'll still have plenty of port area.

For the power, that's a LOT of power - set the gains correctly (no clipping - match the amp gain to the head deck please!), set the subsonic filter at 30 Hz. But most importantly get the gains right - don't just eyeball it or set it by ear.

If it were me, I'd plug one port, and get Brahma D2s, wire the voice coils in series, and parallel the two drivers, giving each driver ~550W. You'll be within 1.7 dB of the full 1100W per driver (thermal compression eating up the other 1.3 dB), it'll sound as loud to the ear, and will be a lot easier on your alternator, amplifier, and drivers.

Dan Wiggins

Adire Audio®

 

[Hundreth 10+ year member]

That is 5 cubic feet for the pair, tuned to 36 Hz? Pretty peaky box... Try blocking one of the Aeroports to drop the tuning frequency to 30 Hz - I think he'll like the sound better and it'll still have plenty of port area.
For the power, that's a LOT of power - set the gains correctly (no clipping - match the amp gain to the head deck please!), set the subsonic filter at 30 Hz. But most importantly get the gains right - don't just eyeball it or set it by ear.

If it were me, I'd plug one port, and get Brahma D2s, wire the voice coils in series, and parallel the two drivers, giving each driver ~550W. You'll be within 1.7 dB of the full 1100W per driver (thermal compression eating up the other 1.3 dB), it'll sound as loud to the ear, and will be a lot easier on your alternator, amplifier, and drivers.

Dan Wiggins

Adire Audio®

Do you think the new Brahmas will be okay with 1000 watts in a sealed box assuming no clipping occurs?

The reason I ask is because it seems as if the new Brahmas are very finnicky with power handling and overly sensitive to anything over rated power. I'm on the verge of ordering one but I like drivers that can take a little bit of abuse just in case. Its not that I'm planning on sending the Brahma gobs of power for a 1 db increase, its that I want a reliable driver especially considering the fact that Adire does not honor their warranty for fried coils.

 

[DanWiggins 10+ year member]

A few things:

1. Our warranty specifically does NOT cover fried voice coils; it's explicitly stated that we do NOT cover burnt voice coils. That's not a matter of us "honoring" a warranty; it's a matter of us telling you what we won't do. Burning a voice coil happens from simply too much power - not a defect in production. You can read the details at http://www.adireaudio.com/WarrantyInfo.htm - it lists what we explicitly do NOT cover (the failures which really only happen from one thing - way too much power).

2. One individual on here claims he blew his Brahma, and has now "returned it". What actually happened was he used so much power in his box that he blew the voice coil out of the gap so hard it lodged on top of the pole piece. When pushed back over to go back into the gap it scraped, because the aluminum former was bent from slamming on top of the pole.

No burnt voice coil, no torn spider, no glue joint that let go. Just ~37mm forward excursion that blew the voice coil out of the gap. Way over-excursed the driver. We offered to repair the driver, and even offered a discount if he'd let us set his gains for him (with an oscilloscope, and showing him how it's done), but that was ignored.

Now it's sitting here waiting for him to make a decision; it's not "returned" because it's not a warrantable issue. We'll fix it, but it's up to him to follow up.

3. Could you send a Brahma 1000W? Sure, if you know what you're doing. Scottie Johnson used to send them 10,000W without burning voice coils. Blew out suspensions, though...

Does that mean you can? If you know what you're doing, you can do it. If you don't I wouldn't recommend it. If you burn the voice coil, we can recone for you but it's not covered under warranty. If you use so much power and play in a high tuned ported box and over-excurse the driver and blow the voice coil out of the gap, well, that's not a manufacturing defect, it's abuse. We don't cover that.

Essentially, if there's a defect in materials or assembly, we'll cover it. If you put a screwdriver through it, burn it up, damage it from overexcursion, drop it on the ground and break the frame, those are on you. Ford won't cover a new engine for me if I run it without oil; we won't cover a voice coil that's cooked so far the anodization burns off.

Dan Wiggins

Adire Audio®

 

[Hundreth 10+ year member]

A few things:
1. Our warranty specifically does NOT cover fried voice coils; it's explicitly stated that we do NOT cover burnt voice coils. That's not a matter of us "honoring" a warranty; it's a matter of us telling you what we won't do. Burning a voice coil happens from simply too much power - not a defect in production. You can read the details at http://www.adireaudio.com/WarrantyInfo.htm - it lists what we explicitly do NOT cover (the failures which really only happen from one thing - way too much power).

2. One individual on here claims he blew his Brahma, and has now "returned it". What actually happened was he used so much power in his box that he blew the voice coil out of the gap so hard it lodged on top of the pole piece. When pushed back over to go back into the gap it scraped, because the aluminum former was bent from slamming on top of the pole.

No burnt voice coil, no torn spider, no glue joint that let go. Just ~37mm forward excursion that blew the voice coil out of the gap. Way over-excursed the driver. We offered to repair the driver, and even offered a discount if he'd let us set his gains for him (with an oscilloscope, and showing him how it's done), but that was ignored.

Now it's sitting here waiting for him to make a decision; it's not "returned" because it's not a warrantable issue. We'll fix it, but it's up to him to follow up.

3. Could you send a Brahma 1000W? Sure, if you know what you're doing. Scottie Johnson used to send them 10,000W without burning voice coils. Blew out suspensions, though...

Does that mean you can? If you know what you're doing, you can do it. If you don't I wouldn't recommend it. If you burn the voice coil, we can recone for you but it's not covered under warranty. If you use so much power and play in a high tuned ported box and over-excurse the driver and blow the voice coil out of the gap, well, that's not a manufacturing defect, it's abuse. We don't cover that.

Essentially, if there's a defect in materials or assembly, we'll cover it. If you put a screwdriver through it, burn it up, damage it from overexcursion, drop it on the ground and break the frame, those are on you. Ford won't cover a new engine for me if I run it without oil; we won't cover a voice coil that's cooked so far the anodization burns off.

Dan Wiggins

Adire Audio®

Sorry for using the word 'honor', I didn't mean it like that. I just wanted to make sure the driver has some headroom for abuse. As we all know humans aren't perfect, music isn't always recorded the same way, and **** happens. Its nice to have a driver that can handle some of those real world issues.

When I made the comment about the drivers seeming finnicky with power handling, it wasn't because of that one guy who blew it... it was more because of your statements regarding the power handling of the driver. One guy on your forum had a KX750.1 and asked if it would be fine, and you seemed to think it was risky. ~750 watts shouldn't be risky for a driver rated at 600 watts provided theres no clipping.

Other than that, I can see where you guys are coming from.

P.S. You should have an option to have the Brahma logo on there, performance comes first but it would give the driver a LOT more character.

 

[DanWiggins 10+ year member]

No problem, just wanted to make it clear that we don't cover burnt voice coils. Honestly, with 400-500W of power is usually enough. Going another 200-250W for ANY driver will at most gain you ~1.5 dB, a barely audible difference.

The issue is that often those asking "well, can I run 800W on a 600W driver if it's not clipping" typically do not have the experience or equipment to guarantee it's not clipping. A heavily clipped amp where the gains are "only set at 3/4" may result in double the power being delivered, and suddently that 800W amp is dropping close to 1600W into it...

Remember, it is power - and power alone - that kills drivers. Whether that power comes from clipping or from pure sine waves doesn't matter. Too much power is too much power. The key is to get things set properly, and if in doubt ask.

If nothing else, the safest approach is to set the gain to match the head deck. If you have a 4V deck, then set the gain knob to 4V. Yeah, you'll have to turn the volume on your deck up to 80-85% of full to get it really going, but that shouldn't be a drawback; you actually have finer volume resolution - and a better S/N ratio for the system - when set that way.

Dan Wiggins

Adire Audio®