Crossoverless

[rbgcc13]

I have been an Altec fan for quite awhile. Thought I'd ask a question in the Walt Bender vain, has anyone ever tried to run the low end cabinets full range (416s) and the same thing for the large format horns? Walt was a proponent of such an approach of high quality drivers running to their natural mechanical cut-off. I understand the delta in output being anyway from 6 to 9 dB between the bottom and top, seems it would give a "fuller" midrange where both drivers are blending. It also would get rid of a bunch of stuff between the amp and speaker and possibly provide a better grip/control of each driver. Is this a totally insane idea and what are your thoughts? BTW, Walt IMHO was an incredible individual, had a heck of an ear for good tunes, always willing to talk to you and give honest appraisals, and is sorely missed. Thanks

[Old Guy]

Well, everybody has an opinion so I'll give mine...don't like the idea.

A lot of overlap also allows for a lot of phase and pattern control issues.... and to me seems exactly the opposite...with the drivers overlapping you have much less control.

All that said, whatever floats your boat. There is only one person that has to be happy with your system.

My opinions have been wrong. And more than once as the redhead is fond of reminding me.

[RonSSS]

I would think that running LF to the HF driver would blow it up. Either electrically or mechanically. They aren't meant to have any appreciable excersion.
I would also think the 416 would get pretty ugly sounding above about 2kHz. Very beamy.
I would think at the least, a simple 6dB/Oct crossover could be used, an inductor in series with the woof and a cap in series with the HF. Folks have done this and liked it. I tried it, and was never satisfied.

Ron

[bowtie427ss]

I would think that running LF to the HF driver would blow it up. Either electrically or mechanically. They aren't meant to have any appreciable excersion.

OK, i'm no expert, but here goes my 2 cents.

First, i agree with you Ron, that this will run the HF driver into dangerous territory for most of us as well as prematurely fatigue the surround.

However, depending on the exact execution and implementation i think i see some real possibilities.

For example, i have a sweet little SET amp that delivers a hair over 5wpc. The OPT's characteristically roll off pretty steep below 70hz. My WAG is that this amp would probably have a hard time breaking a healthy large format driver, even with no crossover in line.

This all has me wondering if there are OPT's that are specifically designed to have intentionally limited or "narrowed" bandwidth, as well as wondering about some of the iron and amps used in tube consoles.

[Old Guy]

OK, i'm no expert, but here goes my 2 cents.

First, i agree with you Ron, that this will run the HF driver into dangerous territory for most of us as well as prematurely fatigue the surround.

However, depending on the exact execution and implementation i think i see some real possibilities.


This all has me wondering if there are OPT's that are specifically designed to have intentionally limited or "narrowed" bandwidth, as well as wondering about some of the iron and amps used in tube consoles.

At very low power the HF wouldn't be in danger. It's excursion that is the issue, not frequency per se.

IOW a driver that can handle 30 watts at 800 would make x excursion. Halve that to 400 and the excursion goes up by the inverse square...IOW 4 times. So theoretically you've reduced the power handling to 1/4 or 7.5 watts. Down to 200 or halve again, and it becomes less than 2 watts. At 100 less than 1/2. So you can see it becomes an issue quickly.:doh:


Narrowing the frequency response of an amp isn't hard at all. But would that be truly crossoverless? I would argue the amp is also a filter at that point. Actually virtually all amps are a filter anyway.

The problem with crossovers is the phase and other issues. Active crossovers reduce this to such a low level as far as I'm concerned it's nil.

I might build a crossoverless system as an experiment...

I miss the old days of making sawdust and reading everything I could get my hands on...

I am not trying to discourage experimentation....by all means do so...just understand most experiments don't pan out. But the fun isn't so much whether it actually works or not as it is anticipating...doing something you have never done and seeing how it turns out...

[bfish]

Eliminating the negatives a crossover introduces is certainly a worthy goal, but it's all been tried long ago. If you find success, I have a few bucks I'd like to invest.

The problem is that no driver plays well (read, with linearity) beyond the 2-3 octave BW it was designed for.

This all has me wondering if there are OPT's that are specifically designed to have intentionally limited or "narrowed" bandwidth...

There are... cheap ones...