Beyma 8AG/N horn or "the Viech"

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
have you finished your viech´s?I´m finding them quite hard to tune the bass and stopping mid/high frequencies from comming through the horn mouth...
what materials are you using to stop this?

Hi, are you still having problems?... I solved mine putting a role of dynavox damping wool just underneath the chassis and stuffing some wool in the room behind the chassis... worked great. I now have a great speaker:)
PS: Dont forget to cut out the dust cap...;) and put a self made phase plug in...:)


http://www.funpic.de/foto/465635#
 
Here is a Link to my Viechs I sold last week...I have no more photos... but what precisly do you want to know?
The material of the phase plugs is aspen wood. I just took a piece of a branch and carved so long till I had the right shape and size. At planet 10 hifi you can see some original plugs...Cyburgs-Viech bei eBay.de: (endet 10.03.11 16:50:59 MEZ)
I know no translation of the site about the Viech... But please ask some questions...!!!
 
sorry about taking so long to reply...I still haven´t managed to solve the bass problem,it really is very bass shy!
I have the foam thing just behind the speaker and some wool fill just under the driver,but still,no significant improvements...
But i´m about to try the dust cap removal mod!Does it do wonders?What improvements in sound did you took notice of?
thank you for your kindness! :D
 
Hi, are you still having problems?... I solved mine putting a role of dynavox damping wool just underneath the chassis and stuffing some wool in the room behind the chassis... worked great. I now have a great speaker:)
PS: Dont forget to cut out the dust cap...;) and put a self made phase plug in...:)


Viech

i´m a bit affraid to cut the dust cap...does the mod work?
does some of the midband coloration disappear with the mod?
 
Last edited:
sorry about taking so long to reply...I still haven´t managed to solve the bass problem,it really is very bass shy!
I have the foam thing just behind the speaker and some wool fill just under the driver,but still,no significant improvements...
But i´m about to try the dust cap removal mod!Does it do wonders?What improvements in sound did you took notice of?
thank you for your kindness! :D

Hi, no problem... what kind of "foam thing" do you have behind the driver? It still must be fluffy! Not stuffed!

Do you have some detail fotos?

Maybe there is a gab somewhere in the box construction?

Where do the boxes stand?

Do you have a nice thin scalpel for cutting? There is really no problem cutting! Just dont cut off too much at one time...you will then see where to stop...
Beyma1
 
Hi, no problem... what kind of "foam thing" do you have behind the driver? It still must be fluffy! Not stuffed!

Do you have some detail fotos?

Maybe there is a gab somewhere in the box construction?

Where do the boxes stand?

Do you have a nice thin scalpel for cutting? There is really no problem cutting! Just dont cut off too much at one time...you will then see where to stop...
Beyma1

I never really took the time to take photos of the construction process,I just cared about listening to it!the foam looks just like the same that cyburg used and that you can see in the original thread pictures.it´s egg crate shaped foam.
the box is completeley sealed,there are no gaps at all...

about the amount of bass,I tried several times to remove damping material from below the driver,but this only results in more mids comming from the horn mouth and in even more coloration...It always sounds a bit too dry for my taste!

And I´ll be choppin´ off that dust cap,today!I really hope to tame the mids a little!
thank you for the replies and for the detailed photo!
 
Last edited:
I dont think this would help... if you had too much bass then yes... I put a rest of carpet underneath...
I made very good experience with Dynavox D 126 material... polyesther wool...
Maybe your stuffing is too thick and blocks all the bass off???
I read egg shaped foam... this is not good I think... foam does not let frequenzies thruogh... it blocks them off...try this dynavox - it is not expensive... 2 packages... and experiment...
 
Last edited:
sorry about taking so long to reply...I still haven´t managed to solve the bass problem,it really is very bass shy!
I have the foam thing just behind the speaker and some wool fill just under the driver,but still,no significant improvements...

I made a pair of Viechs with and for a friend. We used the method recommended by Cyburgs (once upon a time on a german diy forum) as it seems to work best: a tightly packed small roll of damping material just below the driver in the cabinet (you can easily unscrew the driver to adjust if required). And NO further damping in the horn !
This works really well. Of course, the PA driver of the Viech isn't designed for really low frequencies, but what is there comes out dry and fast. You can also put them somewhat near a corner (experiment to adjust) to increase the bass volume.

My one remark about the viech is that the Beyma, though sounding remarkably musical, lacks sparkle in the high frequencies. I'm pushing my friend to add a simple supertweeter, crossing at say 9000 hertz (to experiment with as well)
 
I made a pair of Viechs with and for a friend. We used the method recommended by Cyburgs (once upon a time on a german diy forum) as it seems to work best: a tightly packed small roll of damping material just below the driver in the cabinet (you can easily unscrew the driver to adjust if required). And NO further damping in the horn !
This works really well. Of course, the PA driver of the Viech isn't designed for really low frequencies, but what is there comes out dry and fast. You can also put them somewhat near a corner (experiment to adjust) to increase the bass volume.

My one remark about the viech is that the Beyma, though sounding remarkably musical, lacks sparkle in the high frequencies. I'm pushing my friend to add a simple supertweeter, crossing at say 9000 hertz (to experiment with as well)

No simple super tweeter!!! Just cut out the dust cap and get or make a phase plug...Its really all you will need...
Greets,Christoph
 
No simple super tweeter!!! Just cut out the dust cap and get or make a phase plug...Its really all you will need...

I can imagine that would increase the treble a bit, but the Viech could use some more precise detail in the higher frequencies than what the humble Beyma can produce, hence I expect more sound profit by adding a supertweeter.

Something else, my own speakers are 65 litres BRs with the Beyma 8BX coax driver. Really happy with them. These experiences and some comments I read here and there make me think that it's in general a pretty good brand.
 
well,it´s been quite some time since the last post but,here it goes... I´ve been fiddling a lot with positioning,stuffing,damping,etc,and the only thing that really solved the bass problem (for me) was something really stupid...I had the drivers only held in place by two wood screws,top and bottom,and besides flexing the chassis,I noticed that they were too tight agaisnt the baffle.I regarded the sound as being too thin and ugly dry,but this happened because the baffle was vibrating like a mad bell!I simply unscrewed the drivers a bit so that the rubber seals would not be squashed against the baffle as well as not allowing any air to escape from the coupling.The result was astonishing since I was getting really annoyed!Though not really really deep,it´s on par with bass levels produced by a good stand mount monitor and now I can even follow bass lines with well recorded material!
As a result of my unnoticed stupidity,the mid´s and high´s on the beyma improved significantly as well!

A good friend helped out with the tweeter (Thank you Carlomar!),a pair of Dayton´s ND20FA and voilá,a truly outstanding loudspeaker!
This is really an excellent project and beware,where I bought the beymas the price has already increased from 18euros to 28euros!That must mean something right?Get them while you can and build these amazing speakers!
 
I´ve been tweaking a lot with the viech and managed to squeeze some more bass from them.We all know that all this depends on the room setup and equipment,but I can honestly say to viech builders that this can work (it did on my setup).

I simply created some sort of compression chamber (don´t know if this is the exact definition),by adding just below the driver, a kind of a lid,leaving just 2,5cm of space between it and the board where we usually apply (according to the viech´s plans) the egg crate foam.
This is all pretty subjective because it´s all down to each and everyones tastes,but now,bass sounds more deep and controled.It also solved a midbass peak and now it sounds more balanced,to my taste of course!

Maybe now it sounds less like a horn,(mids and high´s are quieter),but for me it worked wonders!:p

I haven´t used any calculations but I guess there´s even more room for improvement (for example,getting more space behind the driver).
 
... this happened because the baffle was vibrating like a mad bell!I simply unscrewed the drivers a bit so that the rubber seals would not be squashed against the baffle as well as not allowing any air to escape from the coupling.

Hi Bubuxxl,

On my speakers i also used this trick to reduce the vibration of the panels.

Glad to see that you continues to develop your Viech;)

regards
 
Hi Carlomar!

Feel free to drop by to listen to them!It´s been a long time since our last conversation!
For a total cost of about 150 euros,they sure play like something more expensive!perhaps not as good as your diy´s but they handle themselves quite well!
keep in touch friend! ;)
 
Fiddling, fiddling and more fiddling...

The beyma´s have really nice mids, but for aproximately 2 years, I´ve been trying to squeeze out some bass out of them and without success...
I tried bass traps, as I know that acoustics are everything, put them in corners, close to walls, far from walls, tried to add a compression chamber of some sort, different kinds of stuffing, suppra baffle... nothing happened.

It sounds very sweet and after removing the dustcap, I simply ditched the tweeter and everything, but there´s absolutely no bass foundation to the music, there´s no weight, and I´m not and never was a bass freak... they sound just too damn dry.

Time to move on then... 80kgs of speaker boxes to put aside. I´ve lost the war...
Such a shame, they showed me things that I have never heard... :(
 
Fiddling, fiddling and more fiddling...

The beyma´s have really nice mids, but for aproximately 2 years, I´ve been trying to squeeze out some bass out of them and without success...
I tried bass traps, as I know that acoustics are everything, put them in corners, close to walls, far from walls, tried to add a compression chamber of some sort, different kinds of stuffing, suppra baffle... nothing happened.

It sounds very sweet and after removing the dustcap, I simply ditched the tweeter and everything, but there´s absolutely no bass foundation to the music, there´s no weight, and I´m not and never was a bass freak... they sound just too damn dry.

Time to move on then... 80kgs of speaker boxes to put aside. I´ve lost the war...
Such a shame, they showed me things that I have never heard... :(

Don't give up yet and try a different driver in that cabinet ! Many builders had good experience with that.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.