SB Acoustics SB20FRPC30-8 based desktop project

[JLGF1]

Where's a good retail source for the absorbing felt? Thx.

 

[ppataki]

Where's a good retail source for the absorbing felt? Thx.

I am sourcing it locally here in Hungary, it is relatively cheap
Not sure if it helps but here is the link:

Zajcsillapitas.net - OVF SOFT filcesített textil lap

OVF filcesített, préselt, gyanta erősítésű textil lap. Hajlékony, többféle kivitelben és vastagságban, öntapadó és sima hátlappal egyaránt kapható.

zajcsillapitas.net

I always use the 16mm thick self-adhesive version

 

[ppataki]

I have finished the paint job but I was not satisfied with the results so I have re-painted the cabinets with a more textured roll in a duotone fashion
The fronts became white and all the other sides match the color of the walls of the room:

And this is how it looks when finished:

I consider the project finished (again)
Really happy with it now! (along with my neighbor who will no longer complain because of the wall-mounting)

 

[Berwhale]

I have finished the paint job but I was not satisfied with the results so I have re-painted the cabinets with a more textured roll in a duotone fashion
The fronts became white and all the other sides match the color of the walls of the room:

And this is how it looks when finished:

I consider the project finished (again)
Really happy with it now! (along with my neighbor who will no longer complain because of the wall-mounting)

They look great! Your desk looks like an Ikea one with a very lightweight worktop (hexagonal cardboard cell) sitting on top of some Alex drawers (I have these too, they're great). Does the worktop resonate at all?

 

[ppataki]

They look great! Your desk looks like an Ikea one with a very lightweight worktop (hexagonal cardboard cell) sitting on top of some Alex drawers (I have these too, they're great). Does the worktop resonate at all?

Thank you!

Yes, that is the same desk indeed
No it does not really vibrate since I am using sorbothane decouplers (you can see them in the pictures if you zoom in)
I can strongly recommend them, they are excellent for anti-vibration

 

[jamescarter1982]

has your opinion about these drivers changed at all ? do you still consider them as excellent as you did ?

 

[ppataki]

has your opinion about these drivers changed at all ? do you still consider them as excellent as you did ?

No, it is the same, they are really excellent drivers (with adequate DSP!)
One of my friends is building a 7.8.4 home cinema system using 11 of these drivers....he made this decision after listening to them at my place

 

[jamescarter1982]

OK thanks I'm building a wall mounted system for my son . I'm torn between this or 4 fatial 3fe25 or peerless tc9 in a little array . they will be supported by a 12inch sub each side .

 

[ppataki]

OK thanks I'm building a wall mounted system for my son . I'm torn between this or 4 fatial 3fe25 or peerless tc9 in a little array . they will be supported by a 12inch sub each side .

A single full range driver will act like a point source whereas the array will act like a line source
I have experience with both (built a Murphy Corner Line Array before my 15" main system).
They sound a bit different, especially the soundstage
I realized that I totally prefer point source, but I guess this is subjective....

 

[jamescarter1982]

think I'll make the speakers in a way that the mid high section can be exchanged for a diff one if we don't like what we start out with . shouldn't be too hard to do with a studio monitor industrial style of design

 

[ppataki]

I have finished the paint job but I was not satisfied with the results so I have re-painted the cabinets with a more textured roll in a duotone fashion
The fronts became white and all the other sides match the color of the walls of the room:

And this is how it looks when finished:

I consider the project finished (again)
Really happy with it now! (along with my neighbor who will no longer complain because of the wall-mounting)

I just noticed that the pictures were gone so re-posting them here:

 

[ernestcarl]

I just noticed that the pictures are gone so re-posting them here:

View attachment 320149
View attachment 320150
View attachment 320151

Not exactly a fan of how much room space this eats up on a small desk, but it still looks very classy indeed.

 

[norman bates]

i like it.

However, a pair sitting 4' away is nothing like sitting 10' away doing home theater.

My 8" full rangers have head sized dispersion at 7'.
Two people wide at 12' assuming the 2 are shoulder to shoulder.

Something to keep in mind.......................

 

[ppataki]

This is how it sounds with full DSP:

 

[styjp]

I know this is a bit off but I have been thinking about this driver lately thinking it could be a viable option to use in a car. I have a Mazda Miata which can fit 2x 8 inch drivers + tweeters.

Is there any reason why these wouldn't be a good driver to use with all the cabin gain and this driver's xmax? I had enough trying to find a good car driver with actual ts parameters available, while paying for premium prices. I tried to post the same question in a car audio forum but as expected replies were less than helpful.

 

[ppataki]

I know this is a bit off but I have been thinking about this driver lately thinking it could be a viable option to use in a car. I have a Mazda Miata which can fit 2x 8 inch drivers + tweeters.

Is there any reason why these wouldn't be a good driver to use with all the cabin gain and this driver's xmax? I had enough trying to find a good car driver with actual ts parameters available, while paying for premium prices. I tried to post the same question in a car audio forum but as expected replies were less than helpful.

Not sure if this will help you but here is my comment:
A pair of these drivers will give you 91.6dB MAX SPL at 24Hz at 1m + the cabin gain - if this is enough for you then you can go for it
What I cannot tell you is how much watts you will need to get to that SPL since I don't know how many liters your cabinets (=your doors) will have
In 12 liters I need 2x45W max, the smaller you go the more watts you will need

Additionally, it is very probable that you will need some DSP to tame these drivers
A low-shelf filter will definitely be needed but ideally also some PEQ filters to smooth out the response based on measurements

 

[styjp]

So I got the drivers and I wanted to try them out before installing in the car. I installed them in an enclosure of some vintage 2-way Sony 8 inch speakers with passive radiators and they seem to have a lot of potential, so now I want to buy another pair (one for the car and one for the speakers).

I need some help deciding what's the best approach to utilise the enclosures as I love their look. The enclosure is about 26L, 15.5x30x56cm

a) Replace the passive radiators and if so with which? I have no idea about radiators and how much difference they will make but my options for 8'' seem to be limited to
SB Acoustics SB20PFCR-00
Dayton Audio Designer DSA215-PR
Dayton Audio DS215-PR
b) change the front panel of the speaker completely and go sealed
c) change the front panel of the speaker completely and go ported
d) leave the old radiators and use it as it is with a low shelf filter

I get the feeling that the current radiators make the mid bass sound muddy. As they are currently they drop really quickly below 75-80 hz. I want to make them reach as low as possible before using DSP.

 

[ppataki]

So I got the drivers and I wanted to try them out before installing in the car. I installed them in an enclosure of some vintage 2-way Sony 8 inch speakers with passive radiators and they seem to have a lot of potential, so now I want to buy another pair (one for the car and one for the speakers).

I need some help deciding what's the best approach to utilise the enclosures as I love their look. The enclosure is about 26L, 15.5x30x56cm

a) Replace the passive radiators and if so with which? I have no idea about radiators and how much difference they will make but my options for 8'' seem to be limited to
SB Acoustics SB20PFCR-00
Dayton Audio Designer DSA215-PR
Dayton Audio DS215-PR
b) change the front panel of the speaker completely and go sealed
c) change the front panel of the speaker completely and go ported
d) leave the old radiators and use it as it is with a low shelf filter

I get the feeling that the current radiators make the mid bass sound muddy. As they are currently they drop really quickly below 75-80 hz. I want to make them reach as low as possible before using DSP.

View attachment 328780

I am glad that you like the SBs

My advice: throw the passive radiator out the window now; it ruins all the quality curves of the speaker (phase, group delay, etc) - no wonder you hear it sounding muddy
Build a simpe sealed cabinet (make sure it is airtight, that is very important)

In a well-stuffed sealed box these drivers will look as follows:
Qtc = 0.5 --> 69 liter
Qtc = 0.577 --> 35 liter
Qtc = 0.707 --> 17 liter (this is what I have done)

So this gives you an idea about the sealed box size - 26 liter would be great (Qtc will be 0.625)

 

[styjp]

I am glad that you like the SBs

My advice: throw the passive radiator out the window now; it ruins all the quality curves of the speaker (phase, group delay, etc) - no wonder you hear it sounding muddy
Build a simpe sealed cabinet (make sure it is airtight, that is very important)

In a well-stuffed sealed box these drivers will look as follows:
Qtc = 0.5 --> 69 liter
Qtc = 0.577 --> 35 liter
Qtc = 0.707 --> 17 liter (this is what I have done)

So this gives you an idea about the sealed box size - 26 liter would be great (Qtc will be 0.625)

That sounds like a plan for tomorrow, good thing I can change just the front of the box. Will try to finish and take measurements.

I would also like your opinion based on this.
a. If I go with the sealed 26L, I will probably need some kind of DSP to reach lets say F3 45hz, correct?
If I want to avoid DSP for ease of use with current amps I already have..
b. would a front ported box make more sense? And if so what tuning and port length and diameter would you use? I don't have knowledge to calculate port noise etc.
c. if I go with the front ported box based on the requested tuning, technically I could play with sealed, ported and aperiodic loading, correct?

Thank you so much for taking the time.

 

[ppataki]

That sounds like a plan for tomorrow, good thing I can change just the front of the box. Will try to finish and take measurements.

I would also like your opinion based on this.
a. If I go with the sealed 26L, I will probably need some kind of DSP to reach lets say F3 45hz, correct?
If I want to avoid DSP for ease of use with current amps I already have..
b. would a front ported box make more sense? And if so what tuning and port length and diameter would you use? I don't have knowledge to calculate port noise etc.
c. if I go with the front ported box based on the requested tuning, technically I could play with sealed, ported and aperiodic loading, correct?

Thank you so much for taking the time.

a. yes, you will need a simple low-shelf to reach to F3 45Hz. Without any DSP your F9 will be 45Hz
b. in a 26L ported box your F6 will be 47Hz, see:

for this you will need a vent with diameter = 65mm, length = 135mm
I would rather go for the sealed but you will decide

c. Well, you will then need to remove the vent and seal the hole to become airtight (not just fill the vent hole)