Tweeter Selection for B&W Matrix 800

[dosik2]

I have two friend with 800D, two versions.
Plus other with 802D
With amps done by me.
It is not a simply speaker but with great performances

One photo of an old configuration ( my friend pass away few years ago)
View attachment 1459845
nr. 4 mono amp 4 x KT150 + tube crossover.
The reservoir of power , in my opinion, is mandatory for this speaker

Thanks for your comments.

As you suggested I might need more amps
or different amps as others suggested.

Gathering all the advices, I will have experiment a lot
and think a lot about the changes.

 

[dosik2]

UMIK-1 as far as I know is quite OK. A calibration file is also available. It may have a limit on the length of the USB cable. Go slowly and carefully, study everything, don't rush anywhere. Measurement will help you a lot in detecting problems.

Thanks for your advice and encouragment.

You are right. Measurement will help a lot and should be
the beginning of the project.

 

[AdamThorne]

I understand that you don't wish to use EQ, but it can be useful as a temporary step, to see if you are on the right track.

It can be tricky to take good acoustic measurements, particularly of a large speaker.

 

[dosik2]

You could mount a new tweeter on the existing faceplate but it's a lottery to find one that is suitable. Even then it would require crossover changes. Best to try some changes in the crossover and could be as simple as increasing the padding, or add a 15R-22R resistor parallel to the tweeter, or a parallel CR to tilt down the top octave. As a test you could try the Yamaha NS-10M trick by placing a tissue over the tweeter to reduce the treble edge.

Don't get hung up on the published FR as can be misleading. Lifting the 2-4kHz dip could make the speaker sound more harsh and introduce fatigue. A lot of speakers have this dip and it's there for a reason to make it more pleasant for the ears.

Check to see if the harshness is coming from the tweeter by disconnecting it as a lot of times it comes from the mid driver.

I checked that the harshness is not from mids.
It is more like prominent treble rather than noise or distortion.

Thanks for the Yamaha NS-10M trick information.
I will try this method can help.

 

[dosik2]

This tweeter looks like a close fit on the flange. Not sure on the hole. The tweeter can be rotated, so screw location does not matter. They are out of stock currently.
https://www.soundimports.eu/en/peerless-by-tymphany-da25tx00-08.html

A x-over can shape the response quite a bit. Deciding what you like, and what you are hearing is the challenge. Measurements help identify the changes.

By the way, the above tweeter is sensitivity 88.94dB.
Can I use it with changes only in tweeter crossover?

I hope to avoid the situation in which I have to change
the midrange and/or bass crossover to reduce the gains.
This was one of my original question in this thread.
What sensitivity is ok? what DCR is ok? something like that.

 

[temp25]

If you measure your tweeter, you will know what sensitivity it is, and therefore what is needed..

In theory, it won't work, if the speaker is actually 93dB.

The RST28f looks like a good one to try. If you can set it in place, cover the gap around the perimeter with painters tape.

The tweeter impedance doesn't really matter.