Bill Fitzmaurice

It's a blown tweeter. The usual cause is a crossover inadequate to provide adequate protection and/or using distortion effects. The Selenium ST304-slf can't go lower than 3.5kHz, which IMO is way too high. If you like the way it sounds my advise is to leave it as is.

Every bass player should have Hoffman's Iron Law figuratively tattooed in their mind's eye. Whatever your guitar'd players are using you need twice that, unless by some miracle yours have volume controls that they don't always set to eleven. Your strings are neither the same length or diameter as guitar strings. The same physics that cause that also apply to your speakers.

I wouldn't consider an active speaker that's not designed for use with electric bass without first trying it.

Quite right. Clipped wave forms are harmful for tweeters, as they can increase the power in the high frequencies well above what what the tweeter normally receives. But no matter how hard the clipping the power will never exceed what the woofer normally receives in the lows. By the OPs description there's no obvious reason for the driver failure. Only an autopsy will reveal it.

Altecs and JBLs had aluminum dust caps ostensibly for the same reason. But the high frequency response of Altecs was considerably better than JBLs, while EVs with paper dust caps had better highs than Altecs, so...

In the real world you'll seldom actually draw more than 100 watts from your amp. Don't worry about it.

There's also kevlar, fiberglass, polyethylene, and my favorite, hemp. If you smoke that cone you really smoke that cone. 😁

Audiophiles would argue about which color sounds best. 😄

Something to consider is if aluminum was intrinsically superior why didn't the industry shift to it en masse? There are two reasons. One is that it's not superior. There are many materials that work well for driver cones. Aluminum is merely one of them. Every speaker manufacturer with any interest in it would have obtained free samples from driver manufacturers to find out for themselves if there was good reason to make the change. It would seem that they did not. Second is that none of them would want to be seen as copying Hartke, in so doing tacitly acknowledging that Hartke was better. There are a number of ways to configure drivers to give different results. Using aluminum cones is one of them, but hardly the only one, nor is aluminum used exclusively to realize better high frequency response. If that was the case why does this subwoofer driver have an aluminum cone? https://www.parts-express.com/Peerless-XXLS-P835016-10-Black-Aluminum-Cone-Subwoofer-4-Ohm-264-1648?quantity=100 Lastly, while Hartke seems to be the only major player that uses aluminum cones for electric bass, they're quite common in the hi-fi world. We're usually unaware of it, as most of them are painted black.

Watch this. All of it if you've got time, but what's most pertinent to this discussion starts at the 3:00 mark.

It's mostly confirmation bias. If you think a speaker will sound a particular way it will. Seeing an aluminum cone the natural assumption is that it will have a brighter sound than pulp, so it does. Going to an aluminum cone was a stroke of marketing genius on Hartke's part, as it separated them from the rest of the pack. The same applies to Markbass. There's nothing special about their drivers, but the yellow cones would lead one to think that they're somehow different. Confirmation bias in audio is pervasive; even those who you'd think would be immune to it are not. That's why good engineers never trust what they think they hear without confirming it with measurements. So are Hartke brighter? I don't know. I've never seen them measured. http://seanolive.blogspot.com/2009/04/dishonesty-of-sighted-audio-product.html

I bet he got it sorted, 12 years ago. 🤪

If it's not ported it's not going to give 'thunderous low-end performance' no matter what the advertising says. It still may suit you, but I'd try it before you buy it.

Good advice, in part because combo cabs tend to be undersized for portability. Amps keep getting smaller and smaller as that aspect of what physics allows is ever changing. The physics of how speakers work is chiseled in stone. Hoffman's Iron Law is just as true today as it was in 1970.

The Micro Stack had problems from day one mainly because it used a sealed cab. With one cab it got along OK, but with a second it couldn't handle the current demand when pushed hard, which with the low sensitivity of a sealed cab in the lows one pretty much had to do. Perhaps they've beefed it up since, but admitting they initially didn't get it right isn't typical corporate behavior.

A system with a few knobs set up by someone who knows what they are doing is always better than one with a lot of knobs set up by someone who doesn't.

Or a Vox AC-30. 😉

You can buy one of Tom Hamilton's B15s for a mere $6k. https://reverb.com/item/68553915-tom-hamilton-s-aerosmith-ampeg-vintage-b-15-flip-top-bass-combo-amp-low-serial-number-early-1960s-6 Maybe it's not the same amp, but we often shared a stage in the 60s where we'd use his B15 and my Bassman. His 30 watt B15 was louder than my 50 watt 2x12 Bassman.

Even when accurate they're not worth much. Is a 500 watt amp ten times louder than a 50 watt amp? Nope. It's twice as loud, assuming they have identical transfer function. That's a long leap as well. Ask anyone with a 50 watt valve amp. 😉

Watts don't matter. If they did one wouldn't be able to gig with an Ampeg B15N. It's the total package that counts. I know that trying before you buy isn't easy, but it's still the best way to find what works for you, well worth investing a day or two.

Not one, other than cables and very rarely a string. When I was touring I had a spare amp, but never had to use it.

Amps don't send watts, they send volts. How much power is consumed by each driver is the product of said volts and current, current depends on the load impedance. In this case where each internal driver is 16 ohms if you add an 8 ohm cab half the power will be consumed by the extension, the other half is split between the two 16 ohm internal drivers. What the impedance switch on the amp does is an unknown, as there's no real explanation in the manual. It may be some sort of current or voltage limiter but that's pure speculation.

In 50 plus years of gigging the only spare pieces of kit I've ever used were cables and strings.

Thanks, but I made an error. The radiation angle of any source only shrinks to 180 degrees when the radiating plane is a wavelength in dimension. Since with direct radiating speakers the radiating plane is the baffle it's called the baffle step frequency. When it's smaller than a wavelength the sound will wrap around the cab, eventually going to 360 degrees as you go lower.

Some of us do. 🤥