Bill Fitzmaurice

Crossing over at the usual 80Hz there's little to no vocals in the subs anyway, nor guitar. But there's plenty of content above 80Hz from both the bass and the kick that should be in the PA. Even when I don't bother with subs I always run the bass and full drum kit through my PA, not for volume, for dispersion.

You'll need more than one. Power and driver displacement requirements go up exponentially as you go down in frequency. If you have a pair of ten loaded tops it will take a pair of eighteen, or very high end fifteen, loaded subs to keep up with them. If it's an outdoor gig you'll have no low frequency boundary reinforcement, which means doubling the sub count for the same result as indoors. All things considered you're best off renting.

Chances are whatever mics are employed are chosen by the sound company hired for the gig. Considering that his EV loaded cabs are incapable of going really low there's no need for anything with extended low frequency range.

Since you brought it up, dispersion. A pair of 210 vertically stacked is better, as everyone can hear it better, yourself included.

He has a valve amp. He does not want his cabs series wired. He does not want a 20 ohm load.

Again? Really? Wasn't this addressed less than 48 hours ago, as well as in the sticky? OK, one more time, with feeling: SS amps have a minimum load, valve amps have a maximum load. Run an SS amp with a load equal to or higher than its minimum load rating, run a valve amp with a load equal to or less than the tap rating.

SS or valve? SS amps have minimum impedance loads, valve have maximum impedance loads. In this case run SS at 2 ohms, valve at 4 ohms.

As far as I'm concerned that article is a myth. My first amp was a '65 Fender Bassman that I bought new. In the US everyone who could afford them played Fender, everyone turned on both the power and the standby switches at the same time after setting up, and everyone used the standby switch for beer, or other substances, breaks. I also never heard a pop from using the switch, or saw a driver or power supply cap damaged as a result. Quoted from a '60s Fender Concert Amp manual: Standby Switch: This switch turns the amplifier on and off. In the Standby position the amplifier is off; however, the tube filaments are left on as to eliminate warm up time, provided that the main Power Switch is on. Use of this feature during short breaks versus using the Power Switch will increase tube life.

There's no need to wait. the amp just won't work until they're warm. The only reason for standby mode is so you can shut down the amp on a break without having to touch the volume, and not have to wait for the tubes to heat again when break is over. Many amps don't even have a standby mode and they're none the worse for wear for the lack of it.

High output from small lightweight cabs requires two things: long excursion neo magnet drivers and cabs made of 12mm plywood with extensive bracing. Neither comes cheap.

Jacks are still around so new amps/cabs can be used with old cabs/amps equipped with jacks. However, Neutrik has made a combination speakon/jack amp output connector for at least fifteen years, so any amp designed within that time frame has no excuse for not having a speakon output. On the cab side the use of an input plate equipped with parallel speakon/jacks might add two quid to the build cost, so there's no excuse for the lack of it there either. To the best of my knowledge there's no legal issue with jacks in Europe. What was made illegal was banana jacks/plugs, as they could fit into AC outlets used in some locales.

I guess they'll do, it just seems like the barrel size is small for speaker cable.

I haven't come across Neutrik that are suitable for speaker extensions. Apparently they want you to use Speakon. 😏

You can make a speaker capable extension using Switchcraft 128 in line jack and 184 plug.

There's no doubt that a 110 loaded with a driver with adequate displacement can suffice for moderate level requirements. The problem lies in knowing if a particular 110 is loaded with a driver that has adequate displacement. It's a spec that should be prominently displayed in the literature for all cabs, but isn't.

If they were wired that way they'd cancel each other. There's no more fighting each other air pressure wise in the cab than two drivers facing the same direction do.

I wouldn't say it's technically all wrong, but like all speakers it cannot get around Hoffman's Iron Law.

There's no technical reason why. If you turn on the B+ power rails before the tubes heat up no harm will come of it, you just won't get any sound out of it until the tube heaters get up to temperature. It never causes a problem for amps that don't have separate switches for the heaters and the B+.

There's no need to wait for the tube heaters to warm up before switching standby to on. The standby is there to allow you to turn off the main power rails while leaving the tube heaters on, so there's no wait to warm them up again after you've had your pint and are ready to play the next set.

Standing waves are a low frequency issue, not midrange. Adiabatic process has nothing to do with how damping and stuffing work. That's also old school theory that tried to use thermodynamics to explain how damping and stuffing functioned before the actual acoustical processes were understood.

To simplify, all cabs need damping for smoother mids. Sealed cabs that sound boomy may be improved with more than just being lined, some may require being fully filled to adequately tame the boom.

That's old school theory, long ago abandoned. Modern speakers are too small for standing waves to arise. If they were large enough for that to happen the wavelengths would be too long to be broken up by stuffing. The air mass with sufficient stuffing density doesn't seem larger to the driver. That said, the effects of both damping and stuffing are real, easily measured, and with sufficiently advanced speaker modeling software predictable.

Cabs should be lined with either open cell urethane foam, rigid fiberglass board insulation, or polyester furniture upholstery batting, 2 to 4 cm thick. Sealed cabs may benefit from being totally filled with pillow stuffing, not foam, and absolutely not fiberglass building insulation. That depends on details about the drivers that you're probably unable to find if you have a store bought speaker. If you're building a cab with plans from a professional designer they should tell you what should be used. One can rightfully infer that if they make no mention of it that they're not from a professional.

Pass band is where the speaker primarily operates. For instance, with a four string you wouldn't care about port velocity below 40Hz, as there's nothing there at sufficient levels to excite it. Full excursion is at the voltage required to reach xmax at the peak above Fb. Not at Fb of course, as that's where excursion is at a minimum. What you don't care about is velocity at maximum Pe voltage, unless you have one of those rare drivers that doesn't reach xmax well below maximum Pe.

In theory you want no more than 20 M/s within the speaker pass band at full excursion, but temper that with knowing most of the power from the electric bass is an octave up from the fundamental frequency of the note you're playing.