Introduction to designing crossovers without measurement

[ShaneF]

I wish I could buy two more of these bass drivers but they're nowhere to be found.

 

[AndrewT]

Next time you build, try to get the treble closer to the mid driver.
You can even trim a bit off the treble faceplate to get it closer still. 10mm cut off would be good.

The higher the crossover frequency, the more important the "closeness" becomes.

 

[ShaneF]

That's an interesting thing you bring up. While the photograph I produced has cheap cell phone lens distortion, the distance between the 2 drivers is 1cm.

However.

I have considered replacing the 4 inch Audax with a Morel 5 inch. I would like the increased power handling and a touch more bottom end from the larger driver. I am considering the Morel CAW 538.

http://solen.ca/wp-content/uploads/CAW538.pdf

 

[djn]

Wow. Great stuff AllenB. As you read in my thread I I building crossovers right now and printed out all your post and will follow them as a starting point. Thanks again.

 

[djn]

I took all the posts that AllenB wrote and turned them into a PDF document so I could print it out to work through my crossover design. Here is a copy if anyone is interested.

 

[AllenB]

That's excellent djn, there has been interest in a printable version. I should learn to make PDF documents this way.

Thank you.

 

[AndrewT]

I took all the posts that AllenB wrote and turned them into a PDF document so I could print it out to work through my crossover design. Here is a copy if anyone is interested.

Which pdf reader/writer did you use?

 

[djn]

Thanks Allen. I laid it out in MS Word, then saved it as a PDF. No need to have Adobe.

 

[AndrewT]

I saw "Word" in file properties.
I had not thought about using Word's pdf export.

 

[djn]

I use it with contracts all the time. That way nothing can be changed by someone else but I can make changes to the word file then save it as a PDF again.

 

[AndrewT]

I use it with contracts all the time. That way nothing can be changed by someone else but I can make changes to the word file then save it as a PDF again.

adobe's pdf reader does not allow editing.

There are some free pdf reader/writers that do allow editing.

 

[djn]

The good thing about Adobe PDF is only the originator can make changes......unless you are dealing with a hacker.

 

[AndrewT]

I have only recently changed from adobe to nitro.

I believe it will allow me to edit a pdf file.

I think this applies to all pdf reader/writers.

It's adobe pdf reader that cannot write.

 

[djn]

I've not heard of Nitro. I have been using MS WORD for most everything I write. Anyway, maybe AllenB can't put the write up on the first page of this thread so others can find it.

 

[AndrewT]

I had a very quick scan through but did not read it.
Could it be possible to add some diagrams?

Thanks for all your work.

 

[djn]

Sure. I'll pm you with my email.

 

[AllenB]

maybe AllenB can't put the write up on the first page of this thread so others can find it.

It looks that way. Not sure it would be compatible with the sites own print view system.

 

[djn]

My mistake Allen. I meant to type can not can't. Fat fingers.

 

[BlackMonk]

Dear Companion Allen B:I would like to ask you (to clarify) and specially to you, there is a lot of encountered opinions about the measurement of Thiele-Small parameters but ( I have to be sensible.there is a lot of opinions stating that small level signals, are unproper, and not reliable, others present "papers" expresing concisely that the real idea of the work of this two remarcable persons (Thiele and Small) stands basically on small signals, would you please "clarify this for me, and others?, Thanks in advance Mr Allen B, and also thanks for your work about Designing crossovers without measurement, A masterpiece, for me an many others...

 

[AllenB]

My understanding is that a speaker is well behaved at low levels. In cases where the voice coil is running hot, and also when the cone is running close to its excursion limit, the results may be compromised.

Since neither of these cases are 'normal' it makes sense to deal with those separately, and to take the measurements at a level within the limits. The results should be the same at different levels within these limits, but if you take them at extremely low levels you'll also have to contend with the noise limits of the test equipment.