Bill Fitzmaurice

By and large the Alpha is better in a sealed cab, the Beta better in a ported cab, but it also depends on the cab particulars.

Alignments are obsolete. Back in the Dark Ages before the PC, when speakers were designed with slide rules and scientific calculators, alignments were devised, to reduce the innumerable possible permutations to just a few, for the sake of simplicity. WinISD still has them listed in the initial calculation stages as starting point, but once you've got to the results page you can change the box volume and tuning frequency at will and it will recalculate the result, with each recalculation being a new alignment. This gives you the ability to try all of those innumerable possible permutations. With slide rule or scientific calculator that was impractical, as each new calculation could take fifteen to thirty minutes to do the calc, and then another thirty minutes to manually chart the result. With a PC and modeling software it's very practical, with each new calculation and chart taking no more than fifteen to thirty seconds, unless you decide to overlay the charts for each new calculation. Then it can take maybe a minute or two for each additional.

If the port is too short it will make for a boomier tone, if too long you lose midbass sensitivity. You should use speaker modeling software to determine the correct length.

It's strange. I've only come across one driver, the Dayton RSS 390-HF-4 subwoofer, that has a rear gasket but not a front gasket. Of course the cab that I specify it in is a horn, so a gasket has to be added. 🙄

The gasket on the front is so you can rear mount them, though that's seldom done today other than in horn loaded cabs. They should have a gasket on the rear of the flange as well, 'tis puzzlement why they all don't. They can be sourced.

You may use 18mm in just about any cabinet. The reason most well designed cabs don't use it is that with adequate bracing 12mm is sufficient with less weight.

Varying the size of a sealed cab by a moderate amount has little effect on the result.

That sound is 95% technique, 5% gear. Bootsy Collins was one of the first, and is still one of the best funk players. Bootsy could play a washtub bass and it would still sound like Bootsy.

My preference is blowing out. Blowing in can result in dust accumulation on the heatsink, reducing its effectiveness over time. I've seen fans with filters to prevent dust from ending up inside, on computers, but not on amps. They're not a panacea either, you have to periodically clean the filters. Pro-sound rack mount power amps can be either in or out flowing, with the fans on either the front or back. With those I've seen occasions where an out flow from one amp can get pulled into the in flow of another amp, leading to a very uncool result.

That's a great driver, but probably overkill/overpriced for your needs.

There's more than one Delta 10. The A version, 8 ohms, has 3.5mm xmax, which is adequate. The B version, 16 ohms, has 1.8mm xmax, which is not adequate. 1.8 mm versus 3.5mm xmax means the B will only take half the voltage, one quarter the power, before heavy distortion occurs. Even the A is no prize, with a resonant frequency (Fs) of 66Hz it's best employed as a PA midbass, with separate subs handling the lows. Both the Alpha 10 and Beta 10, with Fs of 50 and 53Hz respectively, are better for electric bass.

From the little I've seen about OEM grade SICA they may not be anything great either. I'd investigate them further before going to the trouble of putting them in.

With only 1.8mm xmax they're not suitable for electric bass. That's roughly half the absolute minimum I specify for use in any of my designs. I guarantee the seller looked at inches and watts and nothing else.

The chart on the LaVoce site is with the driver mounted in a wall. That's how raw driver response is measured. It doesn't reflect response when in an enclosure, which totally changes low frequency response. It should only be used to compare the half-space response of various drivers above 200Hz.

OK, I see that on the catalog page. It's wrong. The low frequency limit is determined by the combination of the T/S specs and the cabinet alignment, so you can't assign an arbitrary number to the low frequency response. Your model is accurate.

Flux is flux, it doesn't matter if the source is neo, ceramic, alnico or field coil.

According to what?

+1. A pair of 2x10 are a lot easier to pack and haul, they can be vertically stacked for much better results than a 4x10, and you can leave one at home when you don't need both. By the looks of it the amp will fit into a standard 19 inch rack case.

I should have been more specific. It was AM radio, with dash board mounted speakers. Gosh awful. Even basic car radios today are far better. I recall an early recording session I did, circa 1970, where the studio monitors were Altec A7s. We listened to the playback and it was quite good. Then the engineer said 'And here's what it's going to sound like in your car', and he switched the playback to a couple of 6x9 inch speakers, with the signal high passed at 100Hz, low passed at 5kHz. It was enough to make one cry.

There is absolutely no data that's of any value in their ad copy. I'd no more take a chance on that than would I on a car that that lists horsepower as 'a lot', 0-100 KPH as 'really fast', and fuel economy as 'quite good'.

Not from personal experience. The only cabs I use are the ones I built. But Barefaced does seem to use better quality drivers than most.

The Basslites come with spades, as do most of the price point Eminence. The higher end in-line Eminence have push terminals, but I've seen OEM Deltalites with spades.

Some was recorded direct, some was recorded through their home built mixing console. Either way there wasn't much there below 70Hz. It wasn't so much because they needed to prevent stylus jump, RIAA equalization took care of that. The main reason was that the primary playback system of the time was car radios, so the sound was mixed to give the best possible result when listened to in a car.

OEMs usually use spades because they're cheaper. In-line drivers tend to use spring loaded binding posts because they're preferred by the DIY crowd. There's no particular advantage to one or the other.

'Divots' and cups to line them can be added. Penn-Elcom is the most likely source of cups.