installed jehnerts with otherwise stock logic 7

[8600RPM]

Ok so finally got my second jehnert installed tonight. I have been running a jehnert under passenger seat and had to wait a couple weeks to install the other one as I damaged one so needed to order another.

I realized you need two spacers under the jehnert to fit into stock enclosures. I also didn't put the oem grill back on but that isn't a big deal to me.

One alone with one oem sound world's better and two sound fabulous much crisper deeper bass and mud bass. Coming from e92 individual audio with jehnerts I was not happy with the muddy sound of logic 7.

I ran jehnerts off oem individual amp for 2 years with no problem at all with hundreds of hours blasting it.

I decided to do same and simply let oem logic 7 drive the jehnerts and again works perfectly, no clipping or shut down after two weeks of blasting it.

Although it technically shouldn't work, I've noticed the jehnerts respond in real world more than their 4 ohm rating since my e92 system was also driving 7 ohm oem woofers but had no problem driving the 4 ohm jehnerts. In comparison I tried a 4 ohm earthquake and it would clip immediately at moderate volume.

So by far the best and easiest upgrade for much clearer sound, much harder, clearer bass, is popping in jehnerts to logic 7 system and you are done.

Technically again your amp could clip but in real world it hasn't happened on my e92 or my f80. Both amps supposed to drive 7 ohm wooders. What's nice with jehnerts is the 100 watts going to each woofer is rated at 7 ohms, so you are getting more like 140 watts per jehnert which is perfect power for the speaker

[Mandi90TT]

What did you use for spacers?

[adc]

More info on the subs you used please?

[3er]

Thanks for sharing.

For those looking to to do the same...a word of caution. Running a solid-state amp rated at a higher resistance (e.g., 8 ohm) than your speakers (e.g., 4 ohm) is not good for the amp (i.e., amp has to work harder). This may not cause issues if the amp is of high quality/overbuilt, but only time will tell.

[mathematics]

that's 100% not true. amp doesn't work harder. you just lose output. that's one of the most absurd things i've heard.

Originally Posted by 3er

Thanks for sharing.

For those looking to to do the same...a word of caution. Running a solid-state amp rated at a higher resistance (e.g., 8 ohm) than your speakers (e.g., 4 ohm) is not good for the amp (i.e., amp has to work harder). This may not cause issues if the amp is of high quality/overbuilt, but only time will tell.

[3er]

Originally Posted by mathematics

that's 100% not true. amp doesn't work harder. you just lose output. that's one of the most absurd things i've heard.

Sorry, but that's not true. You have it backwards. I'd also place your aggression elsewhere.

"When matching amplifiers to loudspeakers, the output impedance of the amplifier should match that of the loudspeakers as accurately as possible, to ensure that the amplifier is able to deliver its maximum rated power. If the speaker impedance is lower than that of the amplifier's output impedance, the amplifier will be forced to work too hard, which will cause overheating and possibly failure. If the amplifier has an overload protection circuit built-in, this may operate and shut down the amplifier, either partially or completely.

If, on the other hand, the speaker impedance is significantly higher than the amplifier's output impedance, the amplifier will be unable to deliver its full power rating, but should in all other respects work normally. Taking an example, if an amplifier with an output impedance of 4(omega) is connected to an 8(omega) loudspeaker, the maximum power available will be half the rated power of the amplifier."

Source: http://www.soundonsound.com/sos/1994...impedance.html

[mathematics]

i apologize. i had what you said backwards. yes, using a 4 ohm driver on an amp rated for a minimal load of 8 ohms would likely cause damage, but not the other way around.

[8600RPM]

Oem woofers are 7 ohm not 8ohm for one. And through experience trying other 4 ohm flat woofers, jehnerts seem to behave much closer to a 5 to 7 ohm woofer from output and it doesn't clip the amp

[Andrew115]

Originally Posted by 8600RPM

Oem woofers are 7 ohm not 8ohm for one. And through experience trying other 4 ohm flat woofers, jehnerts seem to behave much closer to a 5 to 7 ohm woofer from output and it doesn't clip the amp

Keep us updated on the outcome over time. I have run mismatches before with no issues on aftermarket amps but never with stock ones. Some people will say it doesn't work others will say it will, your the only one that can truly report back so please do.

Its not mathematically perfect but it may work fine.

[adc]

Originally Posted by 8600RPM

Oem woofers are 7 ohm not 8ohm for one. And through experience trying other 4 ohm flat woofers, jehnerts seem to behave much closer to a 5 to 7 ohm woofer from output and it doesn't clip the amp

Do you have a link to these jehnerts?

[BeamerandBimmer]

Please post more info on the subs. Cat.# and price/place to order?

[8600RPM]

Don@unexpectedcreations.Com is the great vendor and audio guy I have always got from

[classic6]

Originally Posted by 8600RPM

Don@unexpectedcreations.Com is the great vendor and audio guy I have always got from

Couldnt agree more! Don is great to deal with!

[Mandi90TT]

Originally Posted by Dave 90TT

What did you use for spacers?

Any answer?

[RocketBoots]

Originally Posted by classic6

Couldnt agree more! Don is great to deal with!

Another shout out for Don. In the car audio world, it doesn't get much better than Don. I believe he is also the only authorized dealer for Jehnert east of the Mississipi

Originally Posted by Dave 90TT

Any answer?

The Jehnerts come with a spacer if you get them from Don. It's ABS plastic (weather resistant), about 1/4" thick, and fits perfectly. You could make it yourself, if you had a router, flush trim bits, jigsaw, etc, but no need. Don will take care of you. His pricing is also very reasonable; fair to you and him.

[Mandi90TT]

Thanks

[8600RPM]

Originally Posted by RocketBoots

Another shout out for Don. In the car audio world, it doesn't get much better than Don. I believe he is also the only authorized dealer for Jehnert east of the Mississipi



The Jehnerts come with a spacer if you get them from Don. It's ABS plastic (weather resistant), about 1/4" thick, and fits perfectly. You could make it yourself, if you had a router, flush trim bits, jigsaw, etc, but no need. Don will take care of you. His pricing is also very reasonable; fair to you and him.

You need two spacers to make jehnerts work on each one. The container that holds the woofer I'd much more shallow on f80 than e92

Need longer screws too

[Vectors2final]

Pics?

[8600RPM]

I didn't take any pics. unfortunately but its easy. Two plastic spacers and bit longer screws. I really tighten them to as I find that makes a big difference in the tightness of bass when installing the jehnerts

[Vectors2final]

Where did you buy them?

[Lincoln30]

Originally Posted by Vectors2final

Where did you buy them?

Bump

[808M3]

There are many misconceptions here, but I don't want to "make any waves".
If you are just replacing speakers, it is highly recommended that you replace them with speakers of same impedance. This is because you don't know how they are connected to each other in the car. If you are wiring your own speakers, you need to know that it makes a big difference.
There are three ways to wire multiple speakers; parallel, series and parallel-series. Each will affect the load presented to an amplifier.

Example: Lets say you are wiring together two 8 ohm speakers.
Parallel wiring: 8 ohm+ 8 ohm = 4 ohms
Series wiring: 8 ohm + 8 ohm = 16 ohms
Parallel-Series: 8 ohm + 8 ohm = 8 ohms

If you are replacing two 8 ohm speakers with 4 ohm speakers and they are wired in parallel, your impedance is now 2 ohms. Most amps will not be "happy" with this, subwoofer amps are an exception. However, if you run two 4 ohm speakers in series, then the impedance will now be 8 ohms.

Hope this helps.