Plattfuss
New member
I tried to find a good answer here and around but still have a question mark over my head.
I hope i don't repost this topic...
I have a 4x12 Cab with Stero Input 2x8 Ohm and Mono 1x12 Ohm from Factory!
Yes 12 Ohm its has 2x8 and 2x16 Ohm Speaker in it by Factory.
So i hooked up the Cap with 2 Speaker Cable as 2x8 Ohm Cabs.
Not sure if that makes a different.
Now i've bought 4 new EVM 12L Speakers with 8 Ohm Factory Print on it.
When i measure the Impedance of the Speakers i measure 4.3, 5.3, 5.0 and 4.7 Ohm.
When i measure other 8 Ohm Speakers from other Manufacture i measure around 6.8 and 7.4 Ohm.
I contact Electronic Voice and asked if that really correct and they say when they have
a Impedance Value everything is ok.
Of course the direct measured Impedance Value is lower than the real Impedance,
but that low for 8 Ohm Speaker and so different Values???
I found in the web more which have measured these Values... even 5.3 for a 16 Ohm labelled.
When i'm correct the Impedance Value of a Speaker is attached to the Frequency of the Signal
with a Range between the direct measured Value as Minimum and even over 40 Ohm and more as Maximum?
Now i asked myself how to hock up Speaker like this to my Herbert.
In a Manual from one of my other Amps (from another Company) i found:
especially for the Herbert.
Is there a Rule for this?
Measured Impedance > Amp Output?
Measured Impedance = Amp Output (only?)
Measured Impedance < Amp Output?
And perhaps what is so special about Electronic Voice to have so different low measured Impedance...?
Best Regards
I hope i don't repost this topic...
I have a 4x12 Cab with Stero Input 2x8 Ohm and Mono 1x12 Ohm from Factory!
Yes 12 Ohm its has 2x8 and 2x16 Ohm Speaker in it by Factory.
So i hooked up the Cap with 2 Speaker Cable as 2x8 Ohm Cabs.
Not sure if that makes a different.
Now i've bought 4 new EVM 12L Speakers with 8 Ohm Factory Print on it.
When i measure the Impedance of the Speakers i measure 4.3, 5.3, 5.0 and 4.7 Ohm.
When i measure other 8 Ohm Speakers from other Manufacture i measure around 6.8 and 7.4 Ohm.
I contact Electronic Voice and asked if that really correct and they say when they have
a Impedance Value everything is ok.
Of course the direct measured Impedance Value is lower than the real Impedance,
but that low for 8 Ohm Speaker and so different Values???
I found in the web more which have measured these Values... even 5.3 for a 16 Ohm labelled.
When i'm correct the Impedance Value of a Speaker is attached to the Frequency of the Signal
with a Range between the direct measured Value as Minimum and even over 40 Ohm and more as Maximum?
Now i asked myself how to hock up Speaker like this to my Herbert.
In a Manual from one of my other Amps (from another Company) i found:
Of course i want to know how "dangerous" is a Impedance mismatch for a Diezel--------------------------------------------------------------------------------
SPEAKER:
The Amp is not very sensitive to impedance mismatching and therefore
we encourage experimentation with regards to speaker loads.
You may feel free to try an 8 Ohm load on the 4 Ohm jack or a 16 Ohm load
on the 8 Ohm jack as you may discover a characteristic that the mismatched
load imparts on the sound that is desirable.
Our 4x12 cabinets are wired in Series/Parallel and are rated at 8 Ohms and
these should normally be connected to the 8 Ohm jack.
When using two of our 8 Ohm 4x12 cabinets, connect them each to a 4 Ohm jack
as doubling the load on each jack produces a total load of 8 Ohms
and is a proper impedance match.
Feel free to use speaker cabinets built by other manufacturers and
these are often wired to produce a 16 Ohm load which you would want
to connect to the 8 Ohm jack. Two 16 Ohm cabinets would be connected
each to an 8 Ohm jack.
Overall our Amp is very impedance friendly and most speaker loads will
work great with the exception of slightly shorter power tube life occurring
when a mismatch in the low direction (two 4 Ohm cabs - each in a 4 Ohm jack
to produce a total load of 2 Ohms) is used for long periods of time.
--------------------------------------------------------------------------------
especially for the Herbert.
Is there a Rule for this?
Measured Impedance > Amp Output?
Measured Impedance = Amp Output (only?)
Measured Impedance < Amp Output?
And perhaps what is so special about Electronic Voice to have so different low measured Impedance...?
Best Regards