Mc42's (Michel) 10P project

[4mc2]

As it sounds that the 10Ps have already been decided upon / procured? I guess all that's left is to decide which enclosure best suits this specific application - did I miss if you've yet discussed any enclosure size constraints?

I have no constraint .... just the best reproduction of sound that I can make .

For me the FHXL is a TQWT( go to slot at down ) + horn . My design before ( the double TQWT ) is a melting pot of TQWT , back horn loaded + OB

I have some experience in back horn loaded with JBL 2220, some time ago , the Qts must to be low ( +/- 0.2 ) for that work very well , the bass is good , deep but not also good articulated that with a OB . The Qts of 10P is a little too high for this model of cabinet .

 

[4mc2]

My design .... free ..... see many page before

The 10P is in the middle , at right , same design for Coral 8" and at left my OB

dimension ; 10" x 5" x 60" ..... noting is critical in the dimension

Good bass , sub not necessary for most music ..... rock also if mid level

 

[4mc2]

........... T h e E n d

 

[lorienblack]

WOW - how do they sound? And what do you find the horn gives you?

Gorgeous - eccentric - wonderful

 

[Assesears]

Great work, how do they sound

 

[markaudio]

Hi Guys,
Thanks to Michel for posting his project. Its very interesting work. Michel will hopefully post his impressions on the acoustic results for this project.

I'm happy to encourage experimentation but bear in mind that results will likely be mixed if a design/application ignore's some of the driver's design features. I have concerns re Michel's horn design. The horns have steep sides that could/will generate reflections and secondary un-controlled resonances. A "tunnelling" effect will also likely be audible.

Horns of these types often generate a musical nuance that for some will be pleasing. I know several audiophiles here in Hong Kong who like this type of enclosure design, especially when combined with vintage wide-band drivers.

With the 10P in mind, its a single-cone (no whizzer, plugs etc), purist single-point-source unit with an intra-wide dispersion patten (low profile cone) that wouldn't normally be used to this type of horn application. Thats not to say the 10P shouldn't be used in this type of design, as it may still create pleasing music. Just bear in mind that if you repeat Michel's design, it might not deliver results that you want. Reading Michel's opinions from his other posts, he has a very individual taste for a certain style of musical character.

Thanks
Mark.

 

[e_fortier]

Hi Michel,

VERY nice project, I sure hope we will have your listening impression.

Merci,
Eric

 

[Scottmoose]

I've already stated very clearly FHXL is not a TQWT. It's a tapped hyperbolic horn with an internal choke. It is one horn, not a collection of disparate parts with something tacked onto the end.

 

[4mc2]

It's not me that open this new thread

Not from Danmark ....... from Quebec , Canada ( French , sorry for my +/- bad english )

I have only 70 hr with it ...... not enough for appreciation of 10P sound ..... good potental !

Hi Guys,
Thanks to Michel for posting his project. Its very interesting work. Michel will hopefully post his impressions on the acoustic results for this project.

I'm happy to encourage experimentation but bear in mind that results will likely be mixed if a design/application ignore's some of the driver's design features. I have concerns re Michel's horn design. The horns have steep sides that could/will generate reflections and secondary un-controlled resonances. A "tunnelling" effect will also likely be audible.

Horns of these types often generate a musical nuance that for some will be pleasing. I know several audiophiles here in Hong Kong who like this type of enclosure design, especially when combined with vintage wide-band drivers.

With the 10P in mind, its a single-cone (no whizzer, plugs etc), purist single-point-source unit with an intra-wide dispersion patten (low profile cone) that wouldn't normally be used to this type of horn application. Thats not to say the 10P shouldn't be used in this type of design, as it may still create pleasing music. Just bear in mind that if you repeat Michel's design, it might not deliver results that you want. Reading Michel's opinions from his other posts, he has a very individual taste for a certain style of musical character.

Thanks
Mark.

Yes Mark , I prefer without horn also for a better stage imaging , but with my size of room , I need some help for the low-mid frequency ( not enough body ) ...... just experimental . I have build this horn for the Audax Pr170ZO , and put on the 10P cabinet just for see .... add some db of mid frequency , more presence of voice . In smaller room the external horn is not necessary . For the two horn inside of cabinet , it's a compromise for to have a cabinet near a open baffle , the back wave never return to back of 10P , he must go to outside directly ( wide open of port ) but you must put some fiber near the port for reduicing velocity of air inside the horn ( Qts only 0.3 )

My design is betwen back loaded horn and open baffle ............ a compromise !

" The horns have steep sides that could/will generate reflections and secondary un-controlled resonances. A "tunnelling" effect will also likely be audible. "

........... not true for short horn ............. a short horn is more a impedance adapter

For now , not absolute , the sound of Beta 8 is better , more alive , more pleasant treble ( violon are a true tone of violon with more nuance in vibrato ) , more body in low mid , faster etc ........... but I have a big room , he must have a good acoustic pressure from driver for put music in full air inside the room .

After 200 or 300 hr .......... another story .............. wait

 

[4mc2]

Finally I have removed the horn ..... it did more harm than good !

With my design I have the best ( partially ) of both world .... a very good bass becausse of two internal bass horn and the clean clean sound from nearly open baffle .

He have many similarity between the tonality of 10P and there of Beta8 .... less the deficiency in low-mid because the smaller cone ...... both are made with long fiber of Japonese paper .

The cost for build this model can be very low ............... +/- $20. for me

The finishing is not perfect perfect ...... but it's not for sale !

 

[Scottmoose]

I'm not entirely convinced that pipe harmonics provide the same 'clean sound as open baffles.' Without dimensions for the cabinet, difficult to assess technical performance, but it will conform to the known laws of physics. Be that as it may though, providing it does what you want it to do & you like the results, that's what counts.

 

[markaudio]

Hi Michel, Guys,
I'm glad Michel has posted an internal pic of his enclosure. Please check the attached pic to this post. Note the red area behind and each side of the driver has no damping. Omitting damping in these areas is not good. There's a real risk of back-wave cancellation effecting the driver's performance. In Michel's design, the internal back and side walls are so close to the driver, its 99% certain they will create some reflection onto the rear of the driver's cone.

As said, I'm all for guys experimenting but its still important to design a box that doesn't significantly compromise the driver's function.

Thanks
Mark.

 

[paul burchell]

Expansion foam insulation ??? interesting

 

[Bob Brines]

Expansion foam insulation ??? interesting

If so, it probably provides some panel damping, but being closed cell, does not provide any wave damping. It just takes up volume.

Bob

 

[paul burchell]

I would assume by the spongy or bubbly look of ex foam when you cut into it that it would be considered open cell but that is just my assumption
but i guess the surface area when cured is smooth and not porous

 

[4mc2]

Hi Michel, Guys,
I'm glad Michel has posted an internal pic of his enclosure. Please check the attached pic to this post. Note the red area behind and each side of the driver has no damping. Omitting damping in these areas is not good. There's a real risk of back-wave cancellation effecting the driver's performance. In Michel's design, the internal back and side walls are so close to the driver, its 99% certain they will create some reflection onto the rear of the driver's cone.

As said, I'm all for guys experimenting but its still important to design a box that doesn't significantly compromise the driver's function.

Thanks
Mark.

Hi Mark , I can put some damping pad near back of driver for see if make a some differenc in sound .

I have tested the 10P in BR before and the sound from my design is more articulated .
He have only reflection near center axe that can return to back of driver but the all other reflexion ( 80% ) can not return ......... physic of wave

Anyway my ear love it ! ...... I am not the first ( some speaker compagnie from France ) that put the back wall very near the drive .
The compacted foam is for more rigid of wall

 

[4mc2]

I have put a small pad around back of drive .......... and the sound if he have difference ,it's very subtle !

I have make a patern of reflexion .......... only the red can have some problem

======================

The best make your proper experience ........ it's the best scholl !

 

[markaudio]

Hi Mc,
I think other diyer's in the past have tried Alpair 12P on the basis that its closer to the Coral 8's size.

I recommend you try the Alpair 12P, better suited to the larger room size.

Thanks
Mark

 

[4mc2]

Hi Mark

Perhaps later !

You know the magnetic power inside the air gap ( voice coil .) .... in Maxwells... for the 12 P and 10P ?

I like to buy your Beta 8 for a friend that search one .

p.s. you know where I can rebuid a old voice coil ( burn ) for a Flat 8 with a copper/aluminum wire like your Alpair have ?

Thanks
Mike