View Full Version : rebuild of Altec N-801 crossovers

08-19-2015, 05:31 AM

Im rebuilding a pair of N-801 crossovers.

I read on another forum that Its recommended to install HF comp to shut down the A7 midrange "shout" and extend the VHF. How Do I do this? Adding Another cap or resistor to the HF?

Much appreciated if someone with this knowledge could guide me in the right direction. I have already bought new replacement parts for the filters but have not installed them yet due to this question.


08-19-2015, 06:17 AM
If it were me, I'd study Zilch's Z19 crossover schematic for hints.


08-19-2015, 06:38 AM

I have studied the Zilch Before and the model 19 crossover.

At the moment I have the 801 crossovers and all the Components to replace the old ones in It. As Im not familiar with this Before I need help where to Place this HF comp in this schematic below.


08-19-2015, 06:41 AM
Is this what to insert after the N-801 crossover to compensate this?


08-30-2015, 01:57 PM
"As you see in the M19 crossover, R2 may be varied to adjust the amount of compensation."

I have been trying to fix the same problems of 'Shouty' sound from HF horns.

The Horn and driver combination I am using - EV DH1012 and Faital Pro LHT142 - are very smooth from 800 to 18kHz but I still wasn't getting the sound I had heard from VOT and other systems.

Since I had a lot of resistors, I experimented with this T-Filter.

First, I used it 'as is' from the diagram and got surprising results. I liked the way cymbals, hi hats and percussion sound much better. As a drummer I like to hear all those things really well.

Next, I increases R2 from 6.5 ohms to 20 ohms to see what happened. Hopefully, this won't be harmful to my amp. Everything seems fine.

I think I like the sound way better.

These are just my first impressions from listening for a short time and no measurements, but I like the way it sounds.

The horns have a nice bright sound similar to nice silk dome tweeters I have used in the past like Scanspeak D2905.

This is my first use of a T-Filter. In the past I always used L circuits for HF driver attenuation.

So far; so good :-)

Good luck!!!

08-31-2015, 12:59 PM
I found this on High Eff Loudspeaker Asylum forum: http://www.audioasylum.com/cgi/vt.mpl?f=hug&m=173756

There are diagrams for the Zilch Z19 crossover including the HF and MF L-Pad controls.

These may be helpful, too:

Have a nice day.