Bill Fitzmaurice

I wouldn't use either, both use too much material where it doesn't do anything useful. This picture compares typical 'window' bracing on the left with the better method on the right: The method on the right is more effective while using less material. I see you also have battens on the corner joints. They serve no purpose, other than adding dead weight, as that's the strongest part of the cabinet, requiring no reinforcement.

[quote name='geoff90guitar' timestamp='1500662124' post='3339518'] What blows a speaker then? [/quote]Too much power. The myth of under powering has as much basis in fact as the Yeti and The Honest Politician.

Distortion does no more harm to a bass driver than does water to a duck's back. Besides, the driver Bergantino uses has a mechanical limit around 200 watts.

I use felt specifically with very small cabs, where a thicker material won't fit well, as a half inch of felt is as effective as an inch and a half of foam or polyester batting. I never pay for felt, I get free scraps from carpet stores. Since it costs them money to have their scraps disposed of they happily give it away. There's no advantage to anything labeled as 'acoustic', other than to those who make and sell it, as that label enables them to charge more for it.

Most of the gigs I play can get away with not going through the PA, as far as the room goes, but I always run the guitar through it so I can hear him through the monitor. Small stages aren't a problem, they're why I designed small monitors. Besides, they have to be there to hear the vocals.

Read this. The same applies to bass cabs. http://www.prosoundweb.com/topics/sound_reinforcement/in_search_of_the_power_alley/ [quote]- neither the guitar or bass go through the PA.[/quote]They should, especially through the monitors, so that everyone can hear everyone else. You would high pass the bass so that nothing below 100Hz is in the monitors. With a stacked rig you can aim the bottom cab away from you to spread the mids and highs, but you'd usually aim it at the drummer, since he'd typically be beside, if not behind, your rig.

[quote name='Lozz196' timestamp='1499723480' post='3333220'] which is best for metal [/quote]Leather.

You can patch acrylic, you have to replace Tolex.

30 pounds.

It depends on how well it's braced. I specify 12mm in most of my designs, not for strength but for ease of construction, as most DIY builders would find jointing with less than 12mm difficult. However, if you've got the woodworking skills and the design is right you don't even need 9mm. My personal cab is a Jack 12 Lite, built from 3mm and 6mm.

It's simple, displacement is the cone area (Sd) multiplied by the linear excursion limit (Xmax). It's just like a car engine bore and stroke, the sum total of which for all the cylinders is the engine displacement, for instance 2000cc. Just like with a car engine the higher the driver displacement the higher the potential output.

I didn't see that, could be. In comparison the Beta 10 that Orange uses in their 410 is 102cc, the Deltalite II 2510 that many manufacturers use is 147cc. 250cc is better than many twelves.

It's never been a big issue compared to all of the driver specs that do matter.The problem lies in getting sufficient accurate data to make an informed choice when the ability to try a number of cabs side by side doesn't exist.

Where it comes to low frequency output watts don't matter, driver displacement does. Vanderkley doesn't list it. Barefaced does for most of their lineup, but not for the newer cabs loaded with tens. Alex needs to attend to that.

Only Eminence can tell you specs on their OEM drivers, and they very well may not. Most speaker manufacturers don't want specs on the drivers they use revealed. I know Ampeg doesn't. Eminence won't even give them to me, and I have a long standing working relationship with them.

[quote name='FinnDave' timestamp='1499027158' post='3328724'] I'll be sticking to my Barefaced cabs with amps outputting approx 50% of their theoretical power handling. I haven't been aware of any problems with that approach. [/quote]This ointment also has a fly in it. Amps are rated at a low THD figure. Pushed to high THD it's the rare amp that won't put out far higher in short bursts, if not long term. I've personally only cooked one driver, ever. It was a 200 watt EVM 15B, and I wasn't even playing through it. I was testing it in a new cab, with a 50 watt amp. I somehow crossed a wire and in less than a heartbeat, so fast that I didn't even hear anything, the voice coil was toast. In the end it boils down to using your ears, along with common sense. If the speakers complain it's too loud, no matter what the amp rating is. If they sound clean you're OK. It's very unusual for any speaker not to distort well below its thermal power rating. FWIW, Barefaced is one brand that uses very high excursion drivers that probably won't distort well below their thermal limit.

[quote name='Twincam' timestamp='1499040406' post='3328808'] Is it not better to achieve a given output using more gain and ask less of the power amp. [/quote]How are you 'asking less of the power amp'?

It doesn't matter if you achieve a given output level with the gain low and volume high or the other way around, the power will be the same.

[quote name='FinnDave' timestamp='1499025942' post='3328709'] I started playing in the 70s, when the accepted standard was a cab rated at double the potential output of the amp. [/quote]In those days real bass drivers were few and far in between, most being generic 'musical instrument' drivers, ie., guitar drivers. They had very short excursion, so you needed lots of them to run clean in the lows. The first rig I had that was capable of running a clean low E with my 50w Fender Bassman was a pair of 4x12 Kustom columns, which had a thermal rating of 150w each. Much has changed since then, mostly with respect to the excursion capability of drivers. For instance, the 50 watt Jensen P12 was often loaded in 2x12 Bassman cabs. Its excursion (xmax) was 1mm. In real world terms that limited it to perhaps 10 watts in the lows before running out of excursion. The xmax of the average twelve inch bass driver today is 5mm. That translates to over four times the power handling before running out of excursion.

[quote name='FinnDave' timestamp='1499018391' post='3328632'] Personally, I would never plug an amp into a cab with a potentially higher output than the cab could handle. Any accidental tweaking of the volume knob could be catastrophic. [/quote]You should get into the ring with a believer in the myth of under-powering, see who wins out. The fly in your particular ointment has to do with the fact that a volume knob position isn't an indicator of how much power the amp is putting out. That depends on a number of factors, starting with the frequency response and output voltage of the pickups, the gain structure throughout the signal chain, EQ boost or cut, speaker impedance with respect to frequency, and so on. Even with the volume knob dimed one set of circumstances can result in the amp running at perhaps a quarter of its rated output, while another set of circumstances could have the amp clipping with the volume control at noon or less. There's a lot of wiggle room with respect to what will work. Having the amp rating anywhere between 1/2 and 2x the speaker rating is probably safe.

[quote name='pawleep' timestamp='1498928691' post='3328071'] was wondering myself if the qes, qts and power; 200 vs 400 rms (deltaPro) are really that much different? [/quote]Different from a driver that was on evilbay four years ago? If I said so it must have been, but that listing is long gone into zombieland, as was this thread until you did an Igor on it.

[quote name='Osiris' timestamp='1498738725' post='3326717'] I want to be sure that it isn't going to be too overpowered that it could potentially damage the Mesa cab before opening my wallet. [/quote]Does it come equipped with a volume knob? If so no worries.

That's called lumber core plywood. It's not as stiff or stable as regular plywood.

[quote name='EliasMooseblaster' timestamp='1497874581' post='3320988'] they've actually specified "due to restrictions, guitars are all DIed, no amplifiers." [/quote]They should spin some CDs with a couple of blokes playing air guitar.

[quote name='EliasMooseblaster' timestamp='1497872428' post='3320957'] I've recently been offered a slot on a gig where we've been told expressly not not to bring any amps at all [/quote]That's OK if there's a house backline, and the gear isn't junk. I'd certainly want to know before booking it. They should have a printed handout of what's there.