In the car stereo world, most aftermarket amps are 2-ohm stable into
stereo loads, even the inexpensive ones. This has been the case for
the last decade, at least. However, the standard for aftermarket car
stereo speakers is still four ohms. I'm talking about component sets
and coaxials, not subwoofers.

I would think that a speaker company could make a bundle offering a
line of 2-ohm component sets and coaxials. As a consumer with an
aftermarket amp, you could double your power by replacing your 4-ohm
speakers with 2-ohm speakers. Or, if you were building a system from
scratch, you could use a smaller amp to get the same power by going
with the lower-impedance speakers.

From an engineering standpoint, would 2-ohm speakers be any harder to
design or more expensive to build? Are there any other technical
drawbacks to designing a 2-ohm speaker?

Scott Gardner

"Scott Gardner" wrote in message

In the car stereo world, most aftermarket amps are 2-ohm stable into
stereo loads, even the inexpensive ones. This has been the case for
the last decade, at least. However, the standard for aftermarket car
stereo speakers is still four ohms. I'm talking about component sets
and coaxials, not subwoofers.

I would think that a speaker company could make a bundle offering a
line of 2-ohm component sets and coaxials. As a consumer with an
aftermarket amp, you could double your power by replacing your 4-ohm
speakers with 2-ohm speakers. Or, if you were building a system from
scratch, you could use a smaller amp to get the same power by going
with the lower-impedance speakers.

From an engineering standpoint, would 2-ohm speakers be any harder to
design or more expensive to build? Are there any other technical
drawbacks to designing a 2-ohm speaker?

There are no serious problems with making 2-ohm speakers, it's done all the
time, particularly for OEM car audio. Due to cost and EMI concerns,
automotive OEMs seriously want to avoid switchmode power supplies. So OEM
systems strongly tend to run off of battery power leaving low-impedance
speakers as an attractive way to build a high-powered system.

The problem is building the power amps to drive the 2-ohm speakers. It too
can be done, but it's not as cost-effective at the modest power levels used
in the mainstream. Then, there's always the problem with trying to change
the customary way of doing things in the mainstream.

On Sat, 3 Jan 2004 06:37:04 -0500, "Arny Krueger"
wrote:

"Scott Gardner" wrote in message

In the car stereo world, most aftermarket amps are 2-ohm stable into
stereo loads, even the inexpensive ones. This has been the case for
the last decade, at least. However, the standard for aftermarket car
stereo speakers is still four ohms. I'm talking about component sets
and coaxials, not subwoofers.

I would think that a speaker company could make a bundle offering a
line of 2-ohm component sets and coaxials. As a consumer with an
aftermarket amp, you could double your power by replacing your 4-ohm
speakers with 2-ohm speakers. Or, if you were building a system from
scratch, you could use a smaller amp to get the same power by going
with the lower-impedance speakers.

From an engineering standpoint, would 2-ohm speakers be any harder to
design or more expensive to build? Are there any other technical
drawbacks to designing a 2-ohm speaker?

There are no serious problems with making 2-ohm speakers, it's done all the
time, particularly for OEM car audio. Due to cost and EMI concerns,
automotive OEMs seriously want to avoid switchmode power supplies. So OEM
systems strongly tend to run off of battery power leaving low-impedance
speakers as an attractive way to build a high-powered system.

The problem is building the power amps to drive the 2-ohm speakers. It too
can be done, but it's not as cost-effective at the modest power levels used
in the mainstream. Then, there's always the problem with trying to change
the customary way of doing things in the mainstream.


But that's my point. Virtually all aftermarket car audio amplifiers
ARE designed to be stable into 2-ohm stereo loads, and have been for
quite a while now. The manufacturers did this originally to give the
consumer the option of bridging the amp into a 4-ohm mono load to
drive a subwoofer. Now, there are more and more monoblocks for
driving subwoofers in cars, so a higher percentage of two-channel amps
are now being used in stereo mode rather than being bridged.

Now we have a situation where the standard car audio amp is 2-ohm
capable for stereo loads, but the standard aftermarket speaker is
still 4 ohms. If it's not any harder for the aftermarket to make
2-ohm speakers, I think there are some significant benefits to using
them.

Scott Gardner

in article , Scott Gardner at
wrote on 1/3/04 4:53 AM:



I would think that a speaker company could make a bundle offering a
line of 2-ohm component sets and coaxials. As a consumer with an
aftermarket amp, you could double your power by replacing your 4-ohm
speakers with 2-ohm speakers. Or, if you were building a system from
scratch, you could use a smaller amp to get the same power by going
with the lower-impedance speakers.

From an engineering standpoint, would 2-ohm speakers be any harder to
design or more expensive to build? Are there any other technical
drawbacks to designing a 2-ohm speaker?


There are drawbacks to building 2 ohm speakers. Getting the lower impedance
requires heavier gauge voice coil wire. This, in turn, increases moving
mass. Besides lowering efficiency (not voltage sensitivity which will
obviously increase somewhat) high coil mass is not desirable on drivers with
relatively light cones. The increased gauge may also require opening of the
gap, reducing flux and consequently further reducing efficiency. There are
workarounds for the problems, such as using an edge wound voice coil or
copper clad aluminum wire. But these will add to cost.
Then there's the issue of larger crossover inductors and potential losses in
the speaker wires themselves. Besides, high power at 4 ohms is pretty easy
to find these days, given that virtually all amps use dc-dc conversion to
obtain high voltage swing. I really don't see the point.

"Scott Gardner" wrote in message

On Sat, 3 Jan 2004 06:37:04 -0500, "Arny Krueger"
wrote:

"Scott Gardner" wrote in message

In the car stereo world, most aftermarket amps are 2-ohm stable into
stereo loads, even the inexpensive ones. This has been the case for
the last decade, at least. However, the standard for aftermarket
car stereo speakers is still four ohms. I'm talking about
component sets and coaxials, not subwoofers.

I would think that a speaker company could make a bundle offering a
line of 2-ohm component sets and coaxials. As a consumer with an
aftermarket amp, you could double your power by replacing your 4-ohm
speakers with 2-ohm speakers. Or, if you were building a system
from scratch, you could use a smaller amp to get the same power by
going with the lower-impedance speakers.

From an engineering standpoint, would 2-ohm speakers be any harder
to design or more expensive to build? Are there any other technical
drawbacks to designing a 2-ohm speaker?

There are no serious problems with making 2-ohm speakers, it's done
all the time, particularly for OEM car audio. Due to cost and EMI
concerns, automotive OEMs seriously want to avoid switchmode power
supplies. So OEM systems strongly tend to run off of battery power
leaving low-impedance speakers as an attractive way to build a
high-powered system.

The problem is building the power amps to drive the 2-ohm speakers.
It too can be done, but it's not as cost-effective at the modest
power levels used in the mainstream. Then, there's always the
problem with trying to change the customary way of doing things in
the mainstream.


But that's my point. Virtually all aftermarket car audio amplifiers
ARE designed to be stable into 2-ohm stereo loads, and have been for
quite a while now.

Aftermarket speakers are widely used with OEM car radios and aftermarket car
radios, not just aftermarket amplifiers. Most of the amplifiers in this
equipment is bridged, so each of the bridged output stages would have to be
effective while working into 1 ohm loads.

In contrast, most aftermarket amplifiers are not bridged, and many of them
are not bridgeable into 2 ohm loads.

"Scott Gardner" wrote in message
...
In the car stereo world, most aftermarket amps are 2-ohm stable into
stereo loads, even the inexpensive ones. This has been the case for
the last decade, at least. However, the standard for aftermarket car
stereo speakers is still four ohms. I'm talking about component sets
and coaxials, not subwoofers.

I would think that a speaker company could make a bundle offering a
line of 2-ohm component sets and coaxials. As a consumer with an
aftermarket amp, you could double your power by replacing your 4-ohm
speakers with 2-ohm speakers. Or, if you were building a system from
scratch, you could use a smaller amp to get the same power by going
with the lower-impedance speakers.

From an engineering standpoint, would 2-ohm speakers be any harder to
design or more expensive to build? Are there any other technical
drawbacks to designing a 2-ohm speaker?

Scott Gardner


4 ohms in parallel is 2 ohms, the more Loudspeakers in a Car equals more
street cred.