Hornresp

Hi There all

I have try to get a strange thing out of a T-TQWT, it looks like there is a shift around 52 Hz, something I do also see in hornresp but when try to make this oke with damping I get not what I want.

can somebody tell me why this happens, is the vistaon with his high VAS a cause?, it will give a bump but with sim in hornresp I can get it alright except in real I can not.

You can see on the hornresp plots one with and one without damping, you can also seen that hornresp is quite precise.

The bump around the 52 Hz is also quite present in the room giving boom.

thanks.

kees
 

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Room Dimensions?

Hi There all

I have try to get a strange thing out of a T-TQWT, it looks like there is a shift around 52 Hz, something I do also see in hornresp but when try to make this oke with damping I get not what I want.

can somebody tell me why this happens, is the vistaon with his high VAS a cause?, it will give a bump but with sim in hornresp I can get it alright except in real I can not.

You can see on the hornresp plots one with and one without damping, you can also seen that hornresp is quite precise.

The bump around the 52 Hz is also quite present in the room giving boom.

thanks.

kees

SWAG: You are measuring the interaction between the sub and the room.

WHG
 
Hi Bill,

I simply use CuteFTP to upload the Setup.exe file to the Hornresp website, kindly hosted by Sabbelbacke on his server. It is not possible for me to take the Hornresp site off-line while the existing file is replaced. I guess the chance of someone trying to download the file in the minute or so that I am uploading a new version is probably pretty remote, and is something that we will just have to learn to live with :).

Kind regards,

David

Depends on how file attributes are set on the server. Most likely access is blocked while file is open for read or write. WHG
 
SWAG: You are measuring the interaction between the sub and the room.

WHG

Tomorrow when rain is over I go try outside, there is no room so I can see if it still happen.

I did see when measure very close to mouth it was a lot better. And yes I have a quite strange room, full of things and a wood stove who resonate happenly.

Close to the mouth it do measure quite good, so you have proberly right.

regards
 

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Depends on how file attributes are set on the server. Most likely access is blocked while file is open for read or write. WHG

Hi Bill,

I was not thinking too clearly yesterday :). When I said that it is not possible for me to take the Hornresp site off-line while the existing file is replaced, I completely overlooked the fact that there is nothing to stop me from temporarily changing the web page.

I will use the following update process in the future:

1. Upload the web page shown in the attachment to prevent downloads.
2. Wait a couple of minutes to allow any downloads currently in progress to be finalised.
3. Upload the new Setup.exe file.
4. Upload the original web page to allow downloads of the new file.

Thanks for the suggestion.

Kind regards,

David
 

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The characterization of endeavors as DIY or Professional are not mutually exclusive concepts.

If David took the same attitude regarding his efforts, you would be SOL!

And, they are certainly at a Professional level albeit, DIY.

WHG

Hi Bill,

The difference is that for me, Hornresp is simply a hobby, whereas for Mark, loudspeakers are his livelihood.

I haven't seen Tom Danley or Earl Geddes giving away too many secrets... :).

Kind regards,

David
 
Hi Bill,

The difference is that for me, Hornresp is simply a hobby, whereas for Mark, loudspeakers are his livelihood.

I haven't seen Tom Danley or Earl Geddes giving away too many secrets... :).

Kind regards,

David

Hi David,

Both Earl and Tom publish (reveal) their design concepts in the public domain,
but seldom do they share data from their lab notebooks.
Trade secrets, of course, are hidden in the minutia of these implementation details. The principal difference between the Amateur DIY and Professional communities, is painstakingly slow and error prone vs. speed and proficiently. In many cases, use of a consultant can yield a successful project concluded at less expense.

Bill
 
I will use the following update process in the future:

1. Upload the web page shown in the attachment to prevent downloads.
2. Wait a couple of minutes to allow any downloads currently in progress to be finalised.
3. Upload the new Setup.exe file.
4. Upload the original web page to allow downloads of the new file.

After thinking about it a bit more, the above process will only work if the Hornresp web page is refreshed by the user on accessing, and is not simply retrieved as a cached page (which would still allow downloads). Because of this, I have decided to leave things as they are :).
 
Tomorrow when rain is over I go try outside, there is no room so I can see if it still happen.

I did see when measure very close to mouth it was a lot better. And yes I have a quite strange room, full of things and a wood stove who resonate happenly.

Close to the mouth it do measure quite good, so you have proberly right.

regards

I did a outside measurement, no room to spoil everything, still the same except some change, I gess the pipe on back of the speaker has or standing waves or fase flips causing canceling, I get nog change but go put reflectors in the corners for as it are standing waves.

strange thing, and yes hornresp predict it right however when stuffing it says it is oke, but I can stuff my complete matras in it it do not help.

Ohh yes the peaky reaction around 20 hz and lower is wind.

regards
 

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Hi there Bill.

Kind of makes me blush that I get an honorable mention with the likes of Earl and Tom.

Earl is retired. And all the more power to him. Hope he enjoys his retirement. We exchange notes from time to time. And I respect his knowledge.

Tom has the privilege of working with a company of people behind him.

Occasionally I have the privilege of emailing Tom to. A very pleasant fellow.

I have me. Sole consultant. I have to do all the work. And there is no pension fund at the end of the rainbow for me as I have been self employed for the greater part of my life.

And I have been plugging away at this for many years.

It is true that without Davids work many things that I can accomplish with ease would be very difficult.

There is a debt there that is not repayable. Ask David how long ago I offered to compensate him for his efforts.

It is also true that I make many contributions that take place in the background for people that I have an interest in their design ideas.

I think I share that with Tom.

Bill Waslo's excellent thread on the Synergy horn is an outstanding piece of collaborative work.


What I have to contend with is coming off of a couple consulting gigs that provided me with no monetary gain but used up a few years of my time.

That is the reality of this business. Not all people I have dealt with are worthy of the trust I gave them. And it is especially painful when I get such a hit in the finances. But never one to take things lying down I press on.

So I change my business model, take a retainer to start work for any new clients and publish little to nothing publicly.

Has not been the route I would like to have taken. But has been the route I have had to follow.
 
Hi there Bill.

Kind of makes me blush that I get an honorable mention with the likes of Earl and Tom.

Earl is retired. And all the more power to him. Hope he enjoys his retirement. We exchange notes from time to time. And I respect his knowledge.

Tom has the privilege of working with a company of people behind him.

Occasionally I have the privilege of emailing Tom to. A very pleasant fellow.

I have me. Sole consultant. I have to do all the work. And there is no pension fund at the end of the rainbow for me as I have been self employed for the greater part of my life.

And I have been plugging away at this for many years.

It is true that without Davids work many things that I can accomplish with ease would be very difficult.

There is a debt there that is not repayable. Ask David how long ago I offered to compensate him for his efforts.

It is also true that I make many contributions that take place in the background for people that I have an interest in their design ideas.

I think I share that with Tom.

Bill Waslo's excellent thread on the Synergy horn is an outstanding piece of collaborative work.


What I have to contend with is coming off of a couple consulting gigs that provided me with no monetary gain but used up a few years of my time.

That is the reality of this business. Not all people I have dealt with are worthy of the trust I gave them. And it is especially painful when I get such a hit in the finances. But never one to take things lying down I press on.

So I change my business model, take a retainer to start work for any new clients and publish little to nothing publicly.

Has not been the route I would like to have taken. But has been the route I have had to follow.


Without the text books, dissertations and published papers to study, where would we all be? By the time I got access to a full acoustics lab, I knew exactly what to do with it. At the present time, my wife and I have over a thousand clients, and most pay there bills eventually. Do not let the deadbeats get you down. There is always some business you should just walk away from. They waste your time and expect something for nothing. We send these folks to our competitors. I also closed my systems consulting practice and now help my wife run her business. The word retirement for me is a misnomer. I suspect for other seniors here, this is true as well.

Do you have a link to BW's thread?

Regards,

Bill
 
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I will use the following update process in the future:

1. Upload the web page shown in the attachment to prevent downloads.
2. Wait a couple of minutes to allow any downloads currently in progress to be finalised.
3. Upload the new Setup.exe file.
4. Upload the original web page to allow downloads of the new file.

A slightly smoother option is to keep Setup.exe stored within a directory named by version number (or upload date). Then the sequence becomes:

1. Create new directory and upload new version to it.
2. Update website to reference new directory.
3. (Optional) Wait for any running downloads to complete and delete old version.
 
A slightly smoother option is to keep Setup.exe stored within a directory named by version number (or upload date).

Hi bgalehouse,

Thanks for the suggestion - it would certainly overcome the corrupted download problem, but with the requirement to have additional directories. As indicated in my previous message I have decided to leave things as they are - the chances of a user downloading a corrupted file are pretty remote anyway, and if they do, they can always just wait a minute or so and try again :).

Kind regards,

David
 
Hornresp Update 3940-151130

Hi Everyone,

Exported AkAbak scripts were showing the variable name Lpt for the length of a throat chamber port or throat adaptor (see Attachment 1). The correct variable name is Lp.

This has now been fixed (see Attachment 2). Simulation results remain the same.

Kind regards,

David
 

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Only if the Hornresp web page is refreshed upon accessing. There is still the potential to download a corrupted file if a cached page is used.

David,

A possibility to consider...

On most servers the "rename" of a file is an atomic operation.
If you uploaded the new "setup.exe" as "newsetup.exe" it would not interfere with any download in progress.

Then, you can simply rename the file on the server from "newsetup.exe" to "setup.exe".

With any luck you should be able to have no window of time for a corrupt download.

Joe L.
(Many thanks for your efforts in creating and constantly improving hornresp.)
 
David,

A possibility to consider...

On most servers the "rename" of a file is an atomic operation.
If you uploaded the new "setup.exe" as "newsetup.exe" it would not interfere with any download in progress.

Then, you can simply rename the file on the server from "newsetup.exe" to "setup.exe".

With any luck you should be able to have no window of time for a corrupt download.

Joe L.
(Many thanks for your efforts in creating and constantly improving hornresp.)

Hi Joe,

Many thanks for your thoughts - this is turning into quite an interesting problem!

Not sure what would happen if NewSetup.exe was renamed as Setup.exe while a user was part-way through downloading old Setup.exe :).

Kind regards,

David
 
Sorry for my late reply, I was busy at work tuning the CNC machines a little for a complex project.

@David
Your upload to the website (both the html files and the setup.exe) is done via FTP - a user downloading it is accessing it via http. The server handles file access and read/write permissions automatically - so in a case where there are two simultanious up/downloads of old/new versions at the same time - the server handles it in this way:

The downloader gets the file he requests, the server keeps this file available. Since its so small, this is no problem for the server-cache in filemanagement.

So even if you are uploading a never version at the same time, this should not cause any trouble.

When the file is uploaded completely, the server then gives the new files "free".

In case both users hit exactly this point, one of them should get a "no access" error - which in the case of the html download then is automatically repeated by the downloading browser, given the small file size the user wouldn´t even notice the small delay..

So in "real world situations", file corruption is only academicaly possible - you can leave everything as it is...

The corrupted download file could result from a great amount of different situations ranging from "disconnection of the dynamic IP from the internet provider" to "proxy failure".... These cases don´t differ from amny other website / download situation in the web and can occur from time to time - simply restart the download - its just a few mb...


Procedures like "copy a new file, then delete the old one and rename the new one it to the old name" make sense in environments where the user-level has more direct access to the file systems and where the old version should be kept as a safe-copy in case the upload of the new files fail. In an FTP/http environment like this, its unnecesary.

Problems on the user/browser side like "getting the old version because of caching" can be resolved by hard-reloading pages to make sure - hit "SHIFT"+"F5" in Firefox (and most others) to reload the page completely, throwing away everything in the cache of the browser that existed before... It shouldn´t be necessary normlaly, but if in doubt, try it.