2 Ohm Capable Lightweight Heads

[agedhorse]

Just to clarify, what amps are you talking about? I'd love to do an AB test here. My margins could not be your margins.

Any of the Subway amps.

 

[Al Kraft]

Any of the Subway amps.

...to be clear in the context of the thread I think you mean that the SW D-350 is fully 4 Ohm stable and the rest of the SW heads are fully 2 Ohm stable...

 

[agedhorse]

...to be clear in the context of the thread I think you mean that the SW D-350 is fully 4 Ohm stable and the rest of the SW heads are fully 2 Ohm stable...

Yes, correct. Since this thread was specifically about 2 ohm capable heads, I left the D-350 out since it's not 2 ohm capable (by design)

 

[DaveDeVille]

... so , just to be clear , is the Magellean 800 2 ohm safe ?
i have two 4 ohm cabs that i might want to run together ...

 

[agedhorse]

... so , just to be clear , is the Magellean 800 2 ohm safe ?
i have two 4 ohm cabs that i might want to run together ...

Minimum load is 2.67 ohms UNLESS the cabinets are Genzler cabinets (which would then be 2 ohms).

This is because the minimum impedance is guaranteed to be high enough to support a 2 ohm minimum load with Genzler cabinets. This is not necessarily true of many cabinets in general.

 

[Jackcrow]

Update on this thread, I ended up going back to the Subway WD-800, which works great.

 

[Andrea Lo]

Just a quick follow up to tell that Jad Freer Audio Sisma is now limited to 950W RMS for certified safe 2Ohm working at any volume. Starting serial number #24.

 

[fishdude101101]

Minimum load is 2.67 ohms UNLESS the cabinets are Genzler cabinets (which would then be 2 ohms).

This is because the minimum impedance is guaranteed to be high enough to support a 2 ohm minimum load with Genzler cabinets. This is not necessarily true of many cabinets in general.

What is fundamentally different with genzler cabs?

 

[Marko 1]

I have a bunch of 4 ohm cabinets so a head that can support a 2 ohm load is ideal for me.

Do any of these cabs match, or a bunch of different make/size cabs that likely won't pair well, anyway?

Someone earlier suggested selling them all and getting some matching 8Ohm cabs,

then any 4Ohm amp would suffice.

 

[agedhorse]

What is fundamentally different with genzler cabs?

It's not just Genzler cabinets but some others too (though without detailed specs, you have no idea), that have made reasonable choices resulting in reasonable minimum impedance values and bandwidths.

There are quite a few cabinets on the market that pay almost no regard to minimum impedance and just stick a nominal number (4 or 8 ohms) on the cabinet and call it good, yet amp designers must design their amps to deal with speaker designers who do not understand the ramifications of ignoring the math.

 

[fishdude101101]

It's not just Genzler cabinets but some others too (though without detailed specs, you have no idea), that have made reasonable choices resulting in reasonable minimum impedance values and bandwidths.

There are quite a few cabinets on the market that pay almost no regard to minimum impedance and just stick a nominal number (4 or 8 ohms) on the cabinet and call it good, yet amp designers must design their amps to deal with speaker designers who do not understand the ramifications of ignoring the math.

I just saw your other post on this. I understand now. Is it possible for two cabs using identical speakers but with different cab design to have widely different minimum impedance?

 

[Jackcrow]

Do any of these cabs match, or a bunch of different make/size cabs that likely won't pair well, anyway?

Someone earlier suggested selling them all and getting some matching 8Ohm cabs,

then any 4Ohm amp would suffice.

Yeah I had some matching pairs but have since gotten rid of them and just stick to my main Bergantino CN212 or Ampeg 810. It’s still nice to have to option to run 2 ohm if I need to.

 

[agedhorse]

I just saw your other post on this. I understand now. Is it possible for two cabs using identical speakers but with different cab design to have widely different minimum impedance?

Not necessarily widely different but certainly different and maybe different enough. The impedance comes from the electrical and mechanical properties of the driver in the enclosure.

 

[fishdude101101]

Not necessarily widely different but certainly different and maybe different enough. The impedance comes from the electrical and mechanical properties of the driver in the enclosure.

So if someone were to use the same drivers as genzler they should be in the same ballpark.

Either way I know my d800+ seems to do quite well with 2ohm load, loudly, for hours so I personally ha w nothing to worry about.

 

[MarkA]

I just saw your other post on this. I understand now. Is it possible for two cabs using identical speakers but with different cab design to have widely different minimum impedance?

Not necessarily widely different but certainly different and maybe different enough. The impedance comes from the electrical and mechanical properties of the driver in the enclosure.

Might crossover design, in two- and three-way cabs, also play a significant part in where and how far the impedance dips?

 

[agedhorse]

Might crossover design, in two- and three-way cabs, also play a significant part in where and how far the impedance dips?

Sometimes, but not too often in bass cabinets.

 

[MarkA]

Sometimes, but not too often in bass cabinets.

Thanks -- I was under the impression that it was a not-infrequent offender, there, but I only understand this stuff in a rather general way and, now that I think about it, am basing my impression on one or two anecdotal cases (where I was told that there were large impedance dips in innoportune ranges, but I don't know how much was due to the drivers, crossover, box design...).

 

[agedhorse]

All 3 have an impact, the drivers generally affect the impedance curve the most, but the enclosure certainly does too at lower frequencies. A lot at resonant frequencies.

 

[Bob Coldwell]

Reviving this thread to see if there are any new contenders.

I'm running a GK MB 500 into two Phil Jones CA 27 cabs, and would like to add one more (8 ohm cabinet).

So, minimum 2.66 ohm impedance would be required.

 

[Averell]

The Eich T1000 is a 2x500 W that can accept 2 ohms load on each output. So you can plug 4 cabs of 4 ohms each. In bridged mode it can only accept 4 ohms load.