Change to Horns or stay Dynamic

Exlibris-

None of the amps you've tried or mention can generate the
2.2kW peaks your speakers are capable of handling.

The Spectron Musician III SE Mk. 2 monos can deliver 7000 watts (and hold it for 500 msec).

But like you say, "the problem isn't amplification, it’s the drivers."

It must be very disappointing to spend over $40K on speakers and find out their drivers come up short of the volume levels you want.

Good luck with your search for new speakers.

Thanks exlibris. There are a few places in Japan with ridiculously large horn systems. I would love to visit a place like those on the ACA page but have no idea if any are open to the public...

Kana813,
Disappointed? Not really. In this hobby I know only too well that "you can have anything you want, you just can't have everything you want."
My guess at this point is that there is a 90% chance that I'll stay with the MBLs and a 10% I'll buy something else.
I'm told that there will soon be a mkII version of the 101Es with a new upper midrange driver. That just may do the trick.

Just quick note from Wikipedia about Woodstock 1969.
Do not think it is irrelevant to home listening.
JBL D140 drivers and Altec horns in good condition is almost impossible to find.

"Sound for the concert was engineered by Bill Hanley, whose innovations in the sound industry have earned him the prestigious Parnelli Award. "It worked very well," he says of the event. "I built special speaker columns on the hills and had 16 loudspeaker arrays in a square platform going up to the hill on 70-foot [21 meter] towers. We set it up for 150,000 to 200,000 people. Of course, 500,000 showed up." ALTEC designed 4 - 15 marine ply cabinets that weighed in at half a ton a piece, stood 6 feet straight up, almost 4 feet deep & a yard wide. Each of these woofers carried four 15-inch JBL LANSING D140 loudspeakers. The tweeters consisted of 4x2-Cell & 2x10-Cell Altec Horns. For many years this system was collectively referred to as the Woodstock Bins"

And now for people who hate math, but have money.
Horns are very simple to understand. Sound pressure is not a linear but logarithmic function:

1. You start at 1 watt.
2. To get first 10 DB above your speaker's sensitivity you need 10 Watt
3. To get second 10 DB you need 100 Watt
4. To get third 10 Db you need 1000 Watt

5. So if you draw the curve.
Your DB's are on vertical scale Y, and your Wattage on horisontal scale X.

From 0 to 1 watt it is almost steeply upward. First watt is the most linear part of the curve.

6. From 1 to 10 watt it is flatten up to ~ 45 degree (compression starts to build up)

7. From 10 to 100 watt the curve goes only 15 degree uphill
8. From 100 to 1000 watt the curve is almost horisontal. You pump 600 more Watts and get 1 db more. Ha Ha.

With horn I have 111 DB with one watt. Nondistorted linear 111db. To get those 111 db with the cone speaker (Sens. 85Db at 1 watt) I need to pump ~750 watt. Guess how heavy the coil will be to handle 750 Watt.

Think.

Sirspeedy,

You have the right guy. It was nice meeting you at the show. That room didn't do much for me. I just wanted to give it a chance.

Rhyno,

Found it a few days ago. Thank you. Romy seems to really hit a few key points in his analysis about horns that line up exactly with what many others say & with what I have heard.

The bass speed & extension limit remains the most difficult to circumvent without having tremendous horns. I need to read more. One thing I will say for sure, understanding design first will allow a more informed choice in speakers. It will also help explain what we hear. The problem with 20 Hz in a horn is the size requirements and length of the horn. Hence all the back loaded horn designs etc.