Bill Fitzmaurice

Another way to look at it is that the lead fuse reveals the current capacity of the wire, which must be equal to or higher than the current draw of the amp. That means you want the lead fuse rating equal to or higher than the amp fuse rating. You can't really go too high, but there's no point in going more than twice the amp fuse rating either. You can feel confident in ignoring the performance claims made by purveyors of leads that resemble fire hoses.

There should be an ampere draw rating on the back of the amp near the mains cord plug socket.

Note that SS and valve amps aren't the same. SS impedance load ratings are minimum, but valve load ratings are maximum. For instance if you have a valve amp with 4 ohm and 2 ohm output taps you'd use 4 ohm with a 2.67 ohm load.

It's not just the amps, it's also the speakers. Ampeg has used Eminence almost as long as Eminence has been around, and Eminence bass drivers have a distinctive rise in the midrange. When emulators are voiced they include the voicing contributed by the speakers.

It could be a suspension separation from the cone, it could also be the voice coil is rubbing.

They're out there. https://www.amazon.com/gp/product/B01LBVWFWC/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Amps and cabs have a built in tone. The purpose of an emulator is to duplicate that tone playing straight through a power amp and FRFR speaker. Playing one through a bass amp and cab isn't what they're made for. OTOH a PA with the EQ set flat is the same as going direct through a power amp and FRFR speaker. If I was to use one I'd send it's output to a power amp and FRFR cab for me to hear and to the PA for the audience to hear.

Compression is good if you don't overdo it. The idea is to reduce high level peaks. Gating is just as useful, to reduce the level of mics not in use, but again you don't want to overdo it.

Because the same settings will sound different in every room. Sometimes you really have to wonder how guys who make money creating sound have no idea how sound works. That's why you take an RTA with your phone. You don't need to guess which frequencies need adjusting or by how much. It's right there for you to see.

You can't adjust EQ from the stage, you have to do it listening or measuring, preferably measuring, out front during sound check.

You might want to consider retiring those cabs. A Barefaced 212 has the same output capability as that of a 3620.

First off, chaining them in series would be 16 ohms. When amps have two outputs they're almost always wired parallel. That's how you get a 4 ohm load from two 8 ohm cabs.

The brand doesn't matter, the specs do. In this case that driver works best in a 300 liter cab, not 90, while the short 3.4mm xmax is barely adequate for electric bass.

You can have a ratio of a ten watts amp to one watt cab and they'll be fine, just don't turn the amp up past the point where the speaker distorts.

The Jensen is not very good. Response is boomy, while it's mechanically limited to 150w.

You only need to calibrate it if you want an SPL reading, which you don't need for seeing the system response.

Did I fail to mention you need separate EQs for monitors and mains? 🫢 EQ adjusts the response to suit the room. However, the room consists of two separate entities, on the stage and in the audience. On the stage you're trying to get maximum intelligibility without feedback, in the audience you're trying to get the best overall sound quality. Seldom the twain do meet.

Bass, and for that matter any instruments, though the PA isn't about volume so much as it's about dispersion. Dispersion is a midbass and higher frequency concern, so high passing the bass at 60 to 80Hz doesn't interfere with it.

High passing both would be double filtering. But that's not necessarily a bad thing. PA pros with high quality DSP crossovers usually use 48dB/octave slopes for maximum mains protection and minimal pass band overlap. It's unusual for the slopes in powered speakers to be that steep, so your thought of trying it both ways is valid.

If you don 't high pass the mains you're at least doubling the stress on their amps and drivers; taking the load off them is one of the reasons for using subs. You also open the possibility of low frequencies from the mains cancelling low frequencies from the subs.

What's the name of the band? The Luddites?

Harshness very often is the result of high THD. That can be sourced with too high a signal level anywhere in the chain, going all the way back to the channel input trim.

+1. That's the myth of underpowering, the notion that clipped signals will kill speakers. If that was the case there could be no such thing as distortion effects. Distortion can toast tweeters, but not because the amp lacks enough power. It's because the abnormally high harmonic content over-powers them.

I did that too, until 20 years ago, when I went to DSP with auto EQ. But you can manually tune EQ almost as easily with one of these on your phone https://play.google.com/store/apps/details?id=radonsoft.net.rta&hl=en_US and one of these for your mixer http://www.flatkeys.co.uk/P!NG.php

EQ isn't optional, it's mandatory. Without it you can't compensate for the room acoustics or tune out feedback. There was a time when I didn't have EQ. That would have been in the early 1980s. 😲