tube amp/speaker match

[vangre]

Could someone suggest what speaker impedence loads give the best results with tube amps?

[planet10]

Depends on your amp... if its a Decware Zen 2-4 ohms work best, if its an OTL 32 ohms would be nice.

dave

[vangre]

HI Dave, How are things in the most beautiful place on the planet? My amp is a Conrad-Johnson CAV 50, an integrated tube amp about 25 watts per channel. I want to build a line array loudspeaker pair and cross over to a Bag End 12" infrasub.
Thanks for the reply, Greg

[Positron]

A good tube amp with OPT and different Z options (4, 8, 16 ohms selections) should mate well with either 4, 8, or 16 ohms.

The Zen is rather unique among tube amps in its low Z matchup of 2 ohms. OTLs, like planet mentions, like higher loads.

[richwalters]

That's one of the beauties about tube amps over all the others. A well designed o/p tranny with multiple secondaries will deliver the right power with the right impedance. Simple.

[planet10]

How are things in the most beautiful place on the planet?

Damp & grey today... but not a hint of snow...

dave

[fdegrove]

Hi,

OTLs, like planet mentions, like higher loads.

Hmmm...Not quite.

That mostly depends on the Zo of the amp and the current drive capability of the valves used.

Since there's no OPT to transform Zo, the typical OTL relies on the Ri and GNFB around the output stage to lower Zo to drive mundane speaker impedances.

Unlike OPT coupled amps it can deliver an enormous amount of current compared to a OPT coupled valve amp even at low impedance depending on valve choice and design.

All of that without all of the inherent limitations of all OPT coupled valve amps.

Bandwidth you can expect from a well designed OTL can be close to DC and go all the way well into the 300KHz range with almost no node shifts.

OTLs need to be heard to be believed, they're the closest to live music I've ever heard.

In LS terms they're not unlike a good full range speaker yet far more extended at both ends of the audio spectrum.

Cheers,

[Positron]

I bet you were thinking of using the 6C33bc tubes?

I see your point. I built an OTL some 12 years ago using 20, 6LF6 tubes, 10 per channel, in triode mode. It drew 850 watts just sitting and was down, calculated and guessed, at around 1.3 mhz at -3db.

Cheers and Merry Christmas.

[fdegrove]

Hi,

I bet you were thinking of using the 6C33bc tubes?

Nope...not really.

Unless you can suggest a way to keep those *****es inline?

I built an OTL some 12 years ago using 20, 6LF6 tubes, 10 per channel, in triode mode. It drew 850 watts just sitting and was down, calculated and guessed, at around 1.3 mhz at -3db.

Sonic bliss does seem to come at a price. OTLs and efficiency aren't synonyms but neither are pure class A designs.

No need to tell you the price of my 100 lbs vinyl spinner, the tonearm or cartridge then?
Not to mention the amp?
Or what the monoblock OTLs eat for breakie?

OK, I shut up.
If you or I hear anything better amp wise, we'll let eachother know, agreed?

It'll better be good,

All the best and a very nice X- Mass to you, Steve.

[planet10]

Originally posted by fdegrove
Or what the monoblock OTLs eat for breakie?

Gym teachers?

dave