What does an inductor do in a speaker crossover?

[goraman]

I have owned Electrostatics, how about 3 to 100 ohm impedance curve !
That's why you need a 355 watt per channel amp and tubes do better with high impedance than SS. when running huge panels.

[Reid Malenfant]

Actually tubes prefer a low impedance as a high one can upset them serioiusly Solid state stuff doesnt mind an open circuit & doesn't like too low an impedance.

So you kind of have it arse about face Jeff, or backwards if you like

Never connect a valve amp up with no speaker or load. A solid state amp wouldn't give a toss

[goraman]

Actually tubes prefer a low impedance as a high one can upset them serioiusly Solid state stuff doesnt mind an open circuit & doesn't like too low an impedance.

So you kind of have it arse about face Jeff, or backwards if you like

Never connect a valve amp up with no speaker or load. A solid state amp wouldn't give a toss

I was given wrong information by a salesmen trying to sell me some big KT88 amps then.

Glad i didn't bite.

[Reid Malenfant]

Well to be 100% truthful it depends on the amp in question Without knowing the tube amp design you won't know if it's safe to work with little or no load, so the safest thing to do is assume that it won't be & give it a proper load

[Stratmangler]

Never connect a valve amp up with no speaker or load. A solid state amp wouldn't give a toss

Not quite true - a single ended amp isn't bothered by having no load.
Never connect a push/pull valve amp with no speaker or load is another matter.

[Reid Malenfant]

Well to be 100% truthful it depends on the amp in question Without knowing the tube amp design you won't know if it's safe to work with little or no load, so the safest thing to do is assume that it won't be & give it a proper load

Not quite true - a single ended amp isn't bothered by having no load.
Never connect a push/pull valve amp with no speaker or load is another matter.

Please look at what I said in the previous post you obviously overlooked

[goraman]

They would have to be some pretty big frickin tubes to drive a massive pair of panels single ended!

[DSJR]

That sales guy wasn't a total loony

"High Impedance" in most speaker cases is around 12 - 15 ohms and this average suits "typical" valve amps really well, as below 8 ohms or so, the higher output impedance of the output transformers may become an issue I understand - unless you are lucky enough to have some Radfords, which were superb in this respect.. Makes a great case for active drive, where modern electronic crossovers can be designed quite easily and have far less interaction than a typical passive crossover..

Having said that - Jeff, have a look at the Tekton site. The M-Lore's look really promising, as they appear on face value to measure properly, have incredibly high efficiency and are cheap to buy if you're US based - getting 'em here a pair at a time doubles the price sadly.. I believe they use Eminence and Fostex drivers to good effect in a variety of designs

[Toppsy]

They would have to be some pretty big frickin tubes to drive a massive pair of panels single ended!

Yes and no.
However, you do need to use DHT transmitter valves of the likes 211, GM70.

I use SET GM70 monoblocks to drive my Quad ESL63's. 35 Watts from a single GM70 and that's running them quite mild at around 1200 Volts. Not for the faint hearted. But they don't half sound good.

Reid Malenfant wrote

Quote:
Originally Posted by goraman View Post
It seems a miracle speaker crossovers work at all.
What alot going on for so few parts.
Jeff it gets worse as no drive unit has a fixed impedance, they all vary all over the place as well which can bugger up the crossover frequency & driver phase. As you can imagine this make things more complicated

& just to make things even worse the driver sensitivity varies over frequency as well

So yeah, it's a minefield out there

One very good reason for Single fullrange driver speakers like Back Loaded Horns etc. NO CROSSOVER! The signal is fed direct to the driver from the amp, so no colouration of the signal by the XO components.

[Reid Malenfant]

One very good reason for Single fullrange driver speakers like Back Loaded Horns etc. NO CROSSOVER! The signal is fed direct to the driver from the amp, so no colouration of the signal by the XO components.

Or actively driven speakers

But then I do agree your full range driver will still have one advantage... Coincidence, that is assuming it is a proper single voicecoil driver Though they are rarely "full range" if the truth be known..