Finding the impedance of an unmarked speaker

[uOpt]

Re: Finding the impedance of an unmarked speaker

I am operating under the rule of thumb (possibly incorrect, as rules of thumb can certainly be) that solid state amps could go with a higher impedance load with no problem, but tube amps were more sensitive to having proper impedance matching.

Solid state amps will simply lose maximum power when you have higher impedance speakers on them. Tube amps take this personally since the output transformer can take damage from it.

Lower impedance sees them work fine, but then they actually gain more maximum power than they are designed for and they can overheat or components can die from too much current. If you were to keep them in the original power envelope things should be fine.

[RealtyViking]

Re: Finding the impedance of an unmarked speaker

I say go for it and see what it sounds like cranked. It has to be better than what is in there now.

[ItsaBass]

Re: Finding the impedance of an unmarked speaker

Solid state amps will simply lose maximum power when you have higher impedance speakers on them. Tube amps take this personally since the output transformer can take damage from it.

Lower impedance sees them work fine, but then they actually gain more maximum power than they are designed for and they can overheat or components can die from too much current. If you were to keep them in the original power envelope things should be fine.

Exactly what my "pre-existing understanding" was, and why I thought it would not be wise to use the speaker.

[Soulcrusher_X]

Re: Finding the impedance of an unmarked speaker

Solid state amps will simply lose maximum power when you have higher impedance speakers on them. Tube amps take this personally since the output transformer can take damage from it.

Lower impedance sees them work fine, but then they actually gain more maximum power than they are designed for and they can overheat or components can die from too much current. If you were to keep them in the original power envelope things should be fine.

There are quite a few amp makers out there that state that a mismatch of higher speaker impedance is okay to be driven by a lower impedance from the amp. Mesa and Geronimo amps actually say to try it like this because the difference can be pleasing to tone and playability. Im not certain, but they may only mention the push-pull amp designs. Would the results be different and possibly damaging because the Skylark is a single-ended design? I used to run a 16 ohm cab into the 8 ohm tap of my Boogie MKIII for years, and no damage occurred.

I know all builders, large-scale and boutique say that too low of an imedance can cause severe damage to tubes, OT, and other components from excessive current feedback, but many say that 1x or 2x impedance increase won't cause damage unless you run the amp flat out with an attenuator or at brain-damaging levels.

Im not trying to push the OP to use the speaker in question with his amp if he doesnt feel its safe. Im sure it will be okay for some noodling around for a test. I would like to hear and learn more. From the stuff Ive read and heard, this always seems to be a touchy subject.

[uOpt]

Re: Finding the impedance of an unmarked speaker

There are quite a few amp makers out there that state that a mismatch of higher speaker impedance is okay to be driven by a lower impedance from the amp. Mesa and Geronimo amps actually say to try it like this because the difference can be pleasing to tone and playability. Im not certain, but they may only mention the push-pull amp designs. Would the results be different and possibly damaging because the Skylark is a single-ended design? I used to run a 16 ohm cab into the 8 ohm tap of my Boogie MKIII for years, and no damage occurred.

I know all builders, large-scale and boutique say that too low of an imedance can cause severe damage to tubes, OT, and other components from excessive current feedback, but many say that 1x or 2x impedance increase won't cause damage unless you run the amp flat out with an attenuator or at brain-damaging levels.

Im not trying to push the OP to use the speaker in question with his amp if he doesnt feel its safe. Im sure it will be okay for some noodling around for a test. I would like to hear and learn more. From the stuff Ive read and heard, this always seems to be a touchy subject.

Right, higher impedance is probably harmless if it's only a factor of 2 or so (8 to 16 Ohm), just losing power.

Higher impedance blows up the output transformer if you go infinity, aka no speaker connected.

[ItsaBass]

Re: Finding the impedance of an unmarked speaker

Ah, WTF. I'll try it and see what happens. But this is an old and cheap amp with teeny weeny dried out and crusty transformers. I'd like to just keep her at stock specs in the end.

[Soulcrusher_X]

Re: Finding the impedance of an unmarked speaker

Well, you dont have to keep it like that forever. It'll just be fun for a few tests.