Bill Fitzmaurice

Watts and loudness are only indirectly related. There are a half dozen factors that have far more effect on loudness than watts, a fact that neither amp nor speaker manufacturers mention in their advertising, because watts drive sales.

Vintage Fenders aren't fussy. We used to run them with anywhere from 8 to 1 ohm loads with never a complaint.

I'd be surprised to see Mesa saying that. Subjectively sounding louder yes, but not more powerful. A watt is still a watt.

With a valve power stage the compression takes place within it, which gives a different result than when it takes before it. There's also a contribution made by the output section power supply, which doesn't happen with SS. For that matter the most sought after valve amps have valve rectification in the power supply, which gives a softer transition into clipping than SS rectification. The addition of SS diodes in place of a 5Y3 or 5U4 valve in Fender amps was one of the reasons why it was said that CBS ruined them, although in truth Fender started using them in some models before the CBS takeover.

The reason is compression. The natural compression of valves reduces the level of transient peaks that cause high level distortion when the amp is at or near full power. It can be approximated with SS using a compressor. It can be very closely approximated with SS using a compressor plus DSP emulation.

Not really. 58Hz f3 is nothing special, nor is 100dB/1w when you have eight of them.

Ampeg is one of the more honest companies, and the 58Hz f3 is accurate, as is the 40Hz f10. They're playing a bit fast and loose when they say 'The Infinite Baffle design of these sealed enclosures produces vast amounts of tightly focused bass.', but nobody's perfect. 😒

Not enough to make it worthwhile. And it's not underpowering the cab per se. It just lacks sufficient power to overcome the cab's poor sensitivity in the lows. You're fighting against Hoffman's Iron Law. It's a futile effort.

Valve amps can work better with lower impedance loads, depending on the output transformer load rating.

The values each of the rheostats would have at any given level of attenuation are the same as those for a fixed LPad, which you calculate with this: https://sengpielaudio.com/calculator-Lpad.htm

You've got a double whammy. The EBS cab is physically too small to have high sensitivity in the lows, the Elf isn't powerful enough to overcome that. The Streamliner can. I'd have no problem driving my 112 with the Elf, but my cab is nearly twice the size of yours.

I get that, but the flaw in your logic is that there's no benefit to pulling the full power from the Elf. All else being equal, and it never is, the difference in the potential maximum output of a 4 ohm versus 8 ohm cab with your amp is roughly 2dB. That's audible, but barely, and it assumes you actually need to pull all of the power out of the amp. You probably don't, and if for some reason you do a pair of 8 ohm cabs will go louder than one 4 ohm cab.

If you want 4 ohms 'to get all the watts out of my amp' that's OK if you never need more than one cab. But if you do you won't be able to, as the ELF has a minimum load of 4 ohms. 8 ohms is more practical, and easier to find. As for 'small...with good lows' those attributes are mutually exclusive, so if you're going small you have to accept that it won't go as low as a larger cab.

Correct. An LPad is a pair of resistors that attenuate a signal while maintaining a constant impedance load, without which a high pass filter won't work. Those resistors can be of set value for a set degree of attenuation, or they may be variable value, for a variable degree of attenuation. They're typically not used to realize flat response. If that was the case they wouldn't have been used on innumerable hi-fi speakers that had drivers of equal sensitivity for the last 75 odd years. Their primary function is to allow the user to tailor the response of a speaker to their own taste. Some speaker designers use fixed value LPads to match the sensitivity of midrange and high frequency drivers to that of the woofer when they are higher, but more often than not they use variable value.

And as noted the impedance of the 1/4" output is ten times what it should be. Combine that with the lack of an XLR input on the power amp and what you have is two non-standard devices that doomed any attempt at using them together.

Quite right. I didn't notice that the only way the Sadowsky pre can deliver the required low impedance output is with the XLR output, while the Sumo doesn't have an XLR input, a curious omission. For that matter the high impedance of the Sadowsky 1/4" output is very unusual.

Don't make more of it than you should. All attenuation does is to turn down the tweeter. If a user can't figure that out they should stick to acoustic instruments. 😉

☺️

Because the average horn loaded high frequency driver has 10dB higher sensitivity than the average woofer attenuation by one means or another is a necessity. It can be with a variable LPad, or with a fixed value LPad, or with DSP. Yes, the bass and preamp can reduce the treble, but their frequency passbands don't necessarily line up with that of the tweeter. Besides, there's nothing wrong with tweeter attenuation, we've been doing it for a hundred years, so why not?

You won't get a good guitar tone from a bass cab, at least not if you plan to overdrive it. It's tough to beat a Celestion Greenback.

The key word is 'top'. They're made to be used along with a subwoofer. Some are capable enough to replace a bass speaker, but by no means all, and short of trying them you have no way of knowing.

Considering the target audience I'd say the ad is spot on. I'm 75 but I haven't forgotten what got me started doing this when I was 15, and it wasn't trying to impress my parents.

True. Just like a box of chocolates when you mix drivers you never know what you're going to get.

If that's too crude you're too old. 😲

The difference between tens and twelves is slight. Just having the combo up on top of the extension will make the high end more obvious. For that matter putting it on a stand would.