Celestion Pulse XL 10.40 Cab

[LeighOnSea]

Hi!
First post (after Welcome forum, from where you could see that I am an absolute begginer)

I have come into the possession of a Celstion PULSE XL 10.20 Bass speaker

PULSE XL 10.20 - Celestion

Great by itself and even better in a 4x10, the PULSE XL 10.20 provides more bass than you’d ever imagine from a 10-inch speaker.

celestion.com

Celestion PULSE XL 10.20 10" 200 Watt Professional Woofer 8 Ohm

Celestion PULSE XL 10.20 10" 200 Watt Professional Woofer 8 OhmThe Celestion PULSE XL 10.20 is a standout 10" professional woofer designed for audio systems that demand high-quality, reliable bass performance. Whether enhancing a studio monitor setup or powering a live concert's sound system...

www.parts-express.com

Also, please see attached pdf

I want to make a ported cab for this, and have looked around this forum for info, and have come to a design

I didnt use WinISD as it looked too complicated and didnt have this driver, didnt work properly on the Win11 on my lappy (which I usually use with Linux), and mostly because I dont know what I want anyway (I just know I love Stranglers, Clash etc and not so much, at all, ever, Level42 and the likes - did see their first songs at Glasto '86 tho until my somewhat befuddled brain realised)

So, I found a subwoofer site SubBox and used that, with the info I got from here. Please dont shoot me.

This is my design

Subwoofer box Celestion PULSE XL 10.20

10 inch subwoofer box design Celestion PULSE XL 10.20, ported box plan, 3D model. Net internal volume 1.70 cubic feet, port area 9.86 square inches, tuning frequency 61.7 Hz. Subwoofer box calculator online

subbox.pro

My design criteria were

1. Cube (I like cubes)
2. Small practice amp to stay at home
3. 16 mm MDF (cheap and it will stay in my house, so heavy / moisture not prob)
4. Minimise cuts of available 400 x 800 mm panels (I'm a Lazy Sod, I'm so Lazeeee)
5. Ported with pipe (PVC water pipe, cheap and available)
6. Tuned Fb to approx 60 Hz (https://www.talkbass.com/threads/cabinet-tuning-frequency.1368101/#post-21873521)
7. Ability to tune to lower frequency if required / wanted (I think since I wont ever play live and like growly punky rocky stuff, perhaps?)

My Design Spiral led to:

Box External Dimensions Width × Height × Depth	400 × 400 × 399.7 mm
Material Thickness	16 mm
Net Internal Volume	48.2 L
Tuning Frequency	61.7 Hz
Port Area	63.6 cm2
Pipe Inner Diameter	90 mm
Pipe Length	15.8 mm

---

I played around with design to with respect to standard PVC water pipe diameters here to give the pipe length the same as the MDF thickness (i.e. no actual pipe required) with an Fb of around 60Hz (c.f. @AstroS https://www.talkbass.com/threads/cabinet-tuning-frequency.1368101/#post-21873521 as my volume is around 1.7 cubic feet)

Then If I want to lower Fb I can put a pipe in of whatever length I like (idea! what about a variable length pipe?) - I think I might like to (?)

I'm going to screw and glue (polyeurathane wood glue) it all together, just with a simple 1/4" jack plug wired straight to speaker (is tip + or - by convention? I know it makes no odds for a single speaker, But I like to be correct )

I'll hole saw out the 90 mm port hole and jigsaw out the 233 mm front panel speaker cutout

So, this is just for fun, very low budget, learning project etc,

Any comments &/or polite suggestions?

Please?

What could possibly go wrong .....

Cheers

Leigh

 

[Dino Boreanaz]

Welcome to the forum! I'm a fellow Clash fan and I'm also working (slowly) on a DIY cabinet ... a sealed 2x10 in my case. I'm certainly not an expert in either design or build, but I've learned a lot from some of the resident experts on this forum, a variety of other online resources, and a few of my own mistakes so my comments are well-intentioned, perhaps somewhat useful, and hopefully not completely incorrect! My suggestions assume that you will not be changing the size of the box or the diameter of the port as you've given very valid reasons for those choices.

I've used WinISD for a few years and have become rather familiar with it even though I understand that its results should not entirely be trusted to be accurate. In fact, I've verified this to be the case when I compared the measured tuning frequency of two cabinets to those predicted by WinISD using the same box and port dimensions and found them to be considerably different than the measured frequencies. This doesn't concern me a great deal as I'm building a sealed cabinet, but I still like to check its results against something else. So, I recently began using a free online calculator at Speaker Box Lite and I've based my comments on those results.

The tuning frequency of almost 62 Hz seems quite high and both WinISD and Speaker Box Lite (SBL) show that it results in a very large peak (about 6 dB) around 75 to 80 Hz. This would certainly be quite noticeable and likely difficult to work around with typical eq controls. I'd suggest a much lower tuning frequency and I've attached two plots from SBL showing the effect of lower tuning frequencies on the frequency response and the port air velocity. It looks like lowering the tuning frequency will reduce the sharp peaking, extend the low end response, and slightly reduce the port air velocity. Although your specific Celestion driver is not available in the SBL database, you can simply select another model and then alter its parameters to those published by Celestion for the Pulse XL 10.20.

As for the build of the cabinet, I tried cutting the baffle hole with a jigsaw at first and was not happy with my result. Your result may be quite different than mine as this is entirely dependent on the skill (and patience) of the operator. I ended up remaking the baffle and used a 230 mm hole saw that I bought online. It's not a great quality cutting tool, and will likely never be used again, but working slowly in a drill press and cutting from both sides of the board, it produced a much nicer opening than I was able to with the jigsaw. I also installed threaded inserts for the mounting holes which I marked, drilled, and installed prior to cutting the large driver hole as they come rather close to the edge of the cutout and I was concerned that they might break through during installation.

As for the polarity convention, I believe the tip is typically connected to positive.

My only other comment is that, based on Celestion's published frequency response graph, this driver does will not have a lot of top-end extension and this may result in a rather dark-sounding cabinet. But since you already have the driver, give it a try and see how you like it. Best of luck and enjoy the journey!

 

[LeighOnSea]

Thanks @Dino Boreanaz !

I did notice in WinISD that I could put the speaker parameters in myself, but there seemed to be so many that I didnt have and wasnt at all sure how to fill them
I have enough experience with Finite Element Analysis of composite materials to know that missing properties can be a nightmare and that if you dont know what you are doing then its easy to make pretty pictures that mean nothing
But you have done that analysis for me, thanks so much!
I will look into SBL too, sounds interesting

So, I have re-tuned to 40 Hz, which was easy as this just increased the 90 mm pipe length from 16 to 164 mm, and then I just readjusted the Net Internal Volume ( which is the adjustable parameter in SubBox) to give the same box dimensions as before

Subwoofer box Celestion PULSE XL 10.2 40Hz

10 inch subwoofer box design Celestion PULSE XL 10.2 40Hz, ported box plan, 3D model. Net internal volume 1.67 cubic feet, port area 9.86 square inches, tuning frequency 40 Hz. Subwoofer box calculator online

subbox.pro

What would happen if I went even lower, say 30 Hz, and would it be worth it? Presumably there is some sort of trade-off here?

I can understand the peak is a problem, but why is vent air velocity a problem - is that what 'chuff' is? (Viz jokes spring to mind)
and what is an acceptable velocity? is it below that red line at 35 m/s (70 knots!)? 16 m/s is 30 knots of wind, which seems a lot but I guess is with not much volume and hence energy. In any case, it seems that going below 40 Hz wont change this much anyway.

Tip to +ve - thanks!

Cutting, I am literally cack-handed so will see if I can set up my router for that - never used yet!

To be honest I was just going to self tap the speaker to the baffle - I bet that's a no-no though
If not I will just through bolt - I will like the look of that, as well as the lack of effort

Dark-sounding cabinet is fine for me! After being a very early teens pocket punk in the late 70's I fully embraced the early Sisters and Bauhaus etc
But getting ahead of myself in this already, in the future could I improve this with a tweeter and a X-over, or something?

Once again, thanks so much for your advice, very very gratefully received

Cheers!

EDIT: My idea was to build then experiment with different length tubes if there was a problem / to get a sound I like. Now I think you have saved me a lot of work in that respect but I can still change the tube length easily and cheaply. In fact, knowing me, I will want to experiment anyway and now have that idea of a variable tuned cab when you can adjust the length of the tube, perhaps simply with a second tube that slides in and out of the main one? Must have been done in one way or another?

 

[agedhorse]

How did you arrive at the original tuning without doing the math? A guess gets you random results, which are usually pretty poor.

From the follow-up plots, your guess appears to be really poor, a lower tuning frequency is obviously indicated.

If the port velocity is too high, unfavorable noises may result. A realistic power handling expectation is an important part of a successful design. The mechanical power handling is at most 200 watts RMS, combined with 92dB/1W/1M sensitivity makes this driver a terrible choice for anything but a low volume solution.

 

[LeighOnSea]

How did you arrive at the original tuning without doing the math? A guess gets you random results, which are usually pretty poor.

From the follow-up plots, your guess appears to be really poor, a lower tuning frequency is obviously indicated.

If the port velocity is too high, unfavorable noises may result. A realistic power handling expectation is an important part of a successful design. The mechanical power handling is at most 200 watts RMS, combined with 92dB/1W/1M sensitivity makes this driver a terrible choice for anything but a low volume solution.

Thanks!
by 'a low volume solution' do you mean a smaller cab? if so like 1 cubic foot?

 

[agedhorse]

Thanks!
by 'a low volume solution' do you mean a smaller cab? if so like 1 cubic foot?

No, low level (ie. quiet)

 

[Dino Boreanaz]

Going even lower on the tuning frequency will likely result in the low-end roll-off becoming more rounded in profile which will reduce the upper bass response (80 to 150 Hz) in exchange for increased low-bass response (20 to 40 Hz). I suggest modelling a variety of tuning frequencies to determine your personal optimum. I've been aiming for something with little to no peaking (perhaps 1 to 2 dB max) with as much area under the curve as possible in the region above 40 Hz.

From my understanding, you're exactly right about the issue with high port air velocity and staying under 5% of the speed of sound should guard against unwanted chuffing. It looks like the orange and red dashed lines on the graph above represent 5% and 10%, so I think they're intended to serve as visual guides.

Good call on using the router for the baffle cutout ... it's always nice to have an excuse to use a new tool!

I don't see any issue with screwing directly into the baffle as long as you don't get tempted to experiment with different drivers. Repeatedly removing and reinstalling screws can chew up the material. But if it does become a problem, you can simply rotate the driver and screw into unused material.

If you're willing to stray from the cube shape, you could make the cabinet shallower with a larger baffle in order to give your future self a place to install a tweeter if necessary. Or do some careful planning of the driver and port locations to leave as much unused area on the baffle as possible ... just in case!

 

[LeighOnSea]

No, low level (ie. quiet)

Great - That's all I want - family already complaining about the 'terrible noise' from my phones

 

[agedhorse]

Great - That's all I want - family already complaining about the 'terrible noise' from my phones

Then you have your answer, though it is usually less expensive to buy a good used cabinet if not looking for high(er) performance.

 

[LeighOnSea]

Then you have your answer, though it is usually less expensive to buy a good used cabinet if not looking for high(er) performance.

Thanks, Yup, I'm sure it is
But my outlay on this is going to be around €40 on top of the €80 I paid for the speaker (an error on my part - I bought the wrong part for something else, so that is already done)
I've already learnt loads. failure is the best way to learn

 

[LeighOnSea]

Going even lower on the tuning frequency will likely result in the low-end roll-off becoming more rounded in profile which will reduce the upper bass response (80 to 150 Hz) in exchange for increased low-bass response (20 to 40 Hz). I suggest modelling a variety of tuning frequencies to determine your personal optimum. I've been aiming for something with little to no peaking (perhaps 1 to 2 dB max) with as much area under the curve as possible in the region above 40 Hz.

From my understanding, you're exactly right about the issue with high port air velocity and staying under 5% of the speed of sound should guard against unwanted chuffing. It looks like the orange and red dashed lines on the graph above represent 5% and 10%, so I think they're intended to serve as visual guides.

Good call on using the router for the baffle cutout ... it's always nice to have an excuse to use a new tool!

I don't see any issue with screwing directly into the baffle as long as you don't get tempted to experiment with different drivers. Repeatedly removing and reinstalling screws can chew up the material. But if it does become a problem, you can simply rotate the driver and screw into unused material.

If you're willing to stray from the cube shape, you could make the cabinet shallower with a larger baffle in order to give your future self a place to install a tweeter if necessary. Or do some careful planning of the driver and port locations to leave as much unused area on the baffle as possible ... just in case!

Thanks!

I am going to build the thing as is @ 40 Hz and then experiment with different pipe lengths to give different Fb tunings and correlate how they each sound to me with the corresponding transfer function plots from the SBL simulations I will also get on to doing.

 

[Dino Boreanaz]

Fantastic! When you get it built, I suggest also doing a simple "rice test" or "salt test" with a tone generator to verify the actual tuning frequency of the finished product. This way you can also check the accuracy of SBL's calculated port length. I'm looking forward to reading about your progress!

 

[MVE]

Thanks, Yup, I'm sure it is
But my outlay on this is going to be around €40 on top of the €80 I paid for the speaker (an error on my part - I bought the wrong part for something else, so that is already done)
I've already learnt loads. failure is the best way to learn

Everything I know in this world I learned by making mistakes.
…It’s probably for the best I never followed my childhood dreams of being a pilot.

 

[LeighOnSea]

Fantastic! When you get it built, I suggest also doing a simple "rice test" or "salt test" with a tone generator to verify the actual tuning frequency of the finished product. This way you can also check the accuracy of SBL's calculated port length. I'm looking forward to reading about your progress!

I will definitely report back
Expect a pause of a week or so as the builders have arrived to resurface my garage / workshop floor
In the meantime I will look into SBL and rice test (jumping due to resonance?)

 

[Dino Boreanaz]

In the meantime I will look into SBL and rice test (jumping due to resonance?)

With a ported cabinet, the rice (I've used salt in the past when I was out of rice) will settle at the tuning frequency as this is when the air in the port is resonating and the cone is experiencing its minimum amplitude. Lay the cab down so the driver is face-up horizontally (prop it up on blocks so you don't have it resting on the plug!) and place a pinch of salt onto the cone; it will slide down and gather at the edge of the dust cap. Play a signal from a computer/phone/etc headphone output into the cabinet using an online tone generator like this or this and sweep through various frequencies. Starting at a quiet volume, you'll find a wide range of frequencies at which the salt does not move. As you increase the volume the salt will experience more motion and you'll be able to narrow in on the resonant frequency quite precisely as the settling will be more obvious at louder volumes.

Good luck with the build and your renovation!

 

[LeighOnSea]

OK, so I made the box, the Leroy Merlin people where I bought the MDF cut it pretty good so I only had to sand down two edges.
It's not perfect, but within glue-line tolerances and good enough for me

At the moment its just screwed together, next step is to cut holes for pipe and speaker, then assemble and glue together.
I will leave one face just screwed for access, any preferences for which one? I'm thinking the top one as its easy to unscrew. I'll use some sort of thin gasket on this face.

It turns out that the diameters of the plastic PVC sewage pipes that I will use are exterior and not interior as I was told by builders. Also I couldnt get a hole saw of 90 mm locally. So I redid the design to use a 50 mm OD (44 ID with wall thickness 3 mm) with Fb of 40 Hz and same 400 x 400 x 400 mm box dimensions - it came out with a pipe length of 16 mm which is worryingly fortunate as that is the MDF thickness.
Tomorrow I'll go swap the 90 mm pipe for a 50 mm one. I have a 50 mm diam hole saw
How should I fix the pipe into the hole in the wood? I dont want to glue it in case I have to change its length. Screws?

One stupid question I have is, 'Does the speaker drop in from the outside (i.e. speaker flange on outside of box) or does the flange screw onto the inside face of the baffle?' I would guess the former?

Cheers!

 

[-Asdfgh-]

Hi!
First post (after Welcome forum, from where you could see that I am an absolute begginer)

I have come into the possession of a Celstion PULSE XL 10.20 Bass speaker

PULSE XL 10.20 - Celestion

Great by itself and even better in a 4x10, the PULSE XL 10.20 provides more bass than you’d ever imagine from a 10-inch speaker.

celestion.com

Celestion PULSE XL 10.20 10" 200 Watt Professional Woofer 8 Ohm

Celestion PULSE XL 10.20 10" 200 Watt Professional Woofer 8 OhmThe Celestion PULSE XL 10.20 is a standout 10" professional woofer designed for audio systems that demand high-quality, reliable bass performance. Whether enhancing a studio monitor setup or powering a live concert's sound system...

www.parts-express.com

Also, please see attached pdf

I want to make a ported cab for this, and have looked around this forum for info, and have come to a design

I didnt use WinISD as it looked too complicated and didnt have this driver, didnt work properly on the Win11 on my lappy (which I usually use with Linux), and mostly because I dont know what I want anyway (I just know I love Stranglers, Clash etc and not so much, at all, ever, Level42 and the likes - did see their first songs at Glasto '86 tho until my somewhat befuddled brain realised)

So, I found a subwoofer site SubBox and used that, with the info I got from here. Please dont shoot me.

This is my design

Subwoofer box Celestion PULSE XL 10.20

10 inch subwoofer box design Celestion PULSE XL 10.20, ported box plan, 3D model. Net internal volume 1.70 cubic feet, port area 9.86 square inches, tuning frequency 61.7 Hz. Subwoofer box calculator online

subbox.pro

My design criteria were

1. Cube (I like cubes)
2. Small practice amp to stay at home
3. 16 mm MDF (cheap and it will stay in my house, so heavy / moisture not prob)
4. Minimise cuts of available 400 x 800 mm panels (I'm a Lazy Sod, I'm so Lazeeee)
5. Ported with pipe (PVC water pipe, cheap and available)
6. Tuned Fb to approx 60 Hz (https://www.talkbass.com/threads/cabinet-tuning-frequency.1368101/#post-21873521)
7. Ability to tune to lower frequency if required / wanted (I think since I wont ever play live and like growly punky rocky stuff, perhaps?)

My Design Spiral led to:

Box External Dimensions Width × Height × Depth	400 × 400 × 399.7 mm
Material Thickness	16 mm
Net Internal Volume	48.2 L
Tuning Frequency	61.7 Hz
Port Area	63.6 cm2
Pipe Inner Diameter	90 mm
Pipe Length	15.8 mm

---

I played around with design to with respect to standard PVC water pipe diameters here to give the pipe length the same as the MDF thickness (i.e. no actual pipe required) with an Fb of around 60Hz (c.f. @AstroS https://www.talkbass.com/threads/cabinet-tuning-frequency.1368101/#post-21873521 as my volume is around 1.7 cubic feet)

Then If I want to lower Fb I can put a pipe in of whatever length I like (idea! what about a variable length pipe?) - I think I might like to (?)

I'm going to screw and glue (polyeurathane wood glue) it all together, just with a simple 1/4" jack plug wired straight to speaker (is tip + or - by convention? I know it makes no odds for a single speaker, But I like to be correct )

I'll hole saw out the 90 mm port hole and jigsaw out the 233 mm front panel speaker cutout

So, this is just for fun, very low budget, learning project etc,

Any comments &/or polite suggestions?

Please?

What could possibly go wrong .....

Cheers

Leigh

WinISD works well on Linux using Wine.

 

[agedhorse]

WinISD works well on Linux using Wine.

I suppose it gives just as inaccurate results too?

 

[LeighOnSea]

WinISD works well on Linux using Wine.

Thanks for info!
But TBH I never got on with Wine, at all
I was using a Windows instance in a virtual box, but then decided that it was just easier to dual boot into Windows when needed

 

[Dino Boreanaz]

Looks great so far!

According to WinISD the port air velocity is over 120 m/s at 40 Hz with the 44 mm ID pipe. I have no experience with these, but everything I've read suggests that this is FAR too high. An 81 mm ID port results in a 35 m/s velocity. Perhaps those who know can offer a reasonable limit or guideline as to an ideal or acceptable port air velocity?

As for how to mount the speaker, most bass cabinets use drivers that drop in from the outside while guitar cabinets use a removable back panel (or are open) and the driver is screwed to the baffle from inside the box. I assume this is done so that the box for bass cabinets can truly be sealed without having to rely on a tight-fit or gasket with a removable rear panel. That's how I'm making my sealed 2x10 ... when it's done the only access to the interior will be through the driver holes.