House Jam Micro Cab

[stevie]

Very neat!

[Phil Starr]

I'm up in Reading brushing up our set with my duo and for a break in the evenings we are hitting the open mics. Tues night we turned up to the loudest sound ever at an 'acoustic' open mic. I actually didn't think the House Jam Cab stood a chance as the rear wall was so far back there woud be no help from there. The guy running it was a bassist who'd toured with name bands back in the 70's. We had the lead for DI into the PA ready and I'd made the obligatory "we're going to need a bigger cab" crack. I turned the amp up plugged the bass cab in and had t turn it down. The response from the host was just WTF and he was still muttering it at the end of our 'set' as I packed up.

 

This cab was meant to push the envelope when I designed it but it still surprises me. It sounds as good as I'd hoped but the volume was really unexpected.

[rwillett]

On 10/06/2022 at 19:23, Pea Turgh said:

Outside finished, just need some port tube and spade connectors.

Yes I am late to this.

 

Yes that is very, very, nice. Where did you get the blue covering from please?

[bremen]

It's paint isn't it? Tuffcab?

[Pea Turgh]

Hello.  It’s just a standard household emulsion in a colour that I fancied, then with two coats of a paint protector of some sort, meant for making standard emulsion wipeable.  Seems to be holding up pretty well still!

[rwillett]

That's very impressive for household emulsion. I love the colour

[bremen]

That it is. I'd never heard of paint protector, could use that throughout my house, garden, studio and bogshed...

[tauzero]

I've used mine at a couple of open mic nights with a 5-string bass, a Tecamp Puma 900, and a degree of caution. Happily kept up with a small PA and sounded good.

[Phil Starr]

I've always loved the look of this @Pea Turgh I'm a lazy so and so when it comes to finish and the corners and handle set it off really nicely reminding me I really should take it more seriously. You've even made the round grille look like it belongs rather than the afterthought it is on my cabs

[Pea Turgh]

22 hours ago, bremen said:

That it is. I'd never heard of paint protector, could use that throughout my house, garden, studio and bogshed...

Just dug out the stuff I used - two coats makes a nice satin finish.  Admittedly, the cab ain’t gigged, but it still looks like new.

Edited September 2, 2024 by Pea Turgh
Grammar

[Pea Turgh]

twit post

Edited September 2, 2024 by Pea Turgh

[rwillett]

43 minutes ago, Pea Turgh said:

Just dug out the stuff I used - two coats makes a nice satin finish.  Admittedly, the cab ain’t gigged, but it still looks like new.

 

It doesn't say it makes an excellent job of finishing speaker cabs on the tin though....

[bremen]

8 minutes ago, rwillett said:

 

It doesn't say it makes an excellent job of finishing speaker cabs on the tin though....

It says "may induce nausea and vomiting if ingested". I tried some, and it really did do exactly what it says on the tin.

[rwillett]

19 minutes ago, bremen said:

It says "may induce nausea and vomiting if ingested". I tried some, and it really did do exactly what it says on the tin.

Your dedication to physically checking and confirming the health and safety information does you credit. 

[tauzero]

BTW, mine demonstrates exactly how to make a round grille look like an afterthought.

 

[cbd]

Hi!

 

I've been gigging a 2x6 cab that I built years ago based on a pair of Faital Pro 6FE100s, and its really come into its own for double bass gigs recently as it's not too subby and I don't need loads of volume. But spotting this thread has inspired me to see if I can slim the rig down even more, so I've bought myself a Fane Sovereign 6-100 and a load more plywood.

 

However, I'm having trouble getting the same results as you in WinISD.

 

I've put in the driver specs as per https://www.fane-international.com/view-product/SOVEREIGN-6-100#tab-1

And have done some maths to guess the internal volume of your design, approx 10.5 litres:

- Internal height 250mm (same as baffle height)

- Internal width 306mm (same as baffle width)

- Internal depth is external depth of 190mm minus the 15mm battens at the front, and the baffle and back panel thicknesses: 190 - 15 - 12 - 12 = 141mm

- Volume of internal battens I and J is 2 * 220mm * 15mm^2 = 0.099 litres

- Volume of internal battens K and M is 2 * 306mm * 15mm^2 = 0.14 litres

- Total volume 250mm * 306mm * 141mm - 2 * 220mm * 15mm^2  - 2 * 306mm * 15mm^2 = 10.55 litres

 

I've set the vent diameter to 64mm, but whatever I set the tuning frequency at, I get quite a different looking graph to what you've got And the calculated port length comes out way too long - e.g. at 70Hz, WinISD is telling me to have a 14cm long port.

 

Any idea what I might be doing wrong? What did you tune the port to on this one?

 

Cheers!

[Phil Starr]

I've just had a look at the saved calculations, my interal volume was assumed to be 10litres and the cab was tuned to 87Hz. I follow WINIsd in terms of inputting the mesured characteristics and leaving WINIsd to calculate the global parameters so you may get different results by using the spec sheet parameters. I'll have tweaked the cab after building the prototype. It's also possible that Fane have either changed the speaker or changed their specs over time. All my designs are built and tested before I share them so may vary from the calculated figures.

 

Hope that helps

[cbd]

Thanks for checking those - unfortunately re-inputting the parameters didn't help but tuning to 87Hz gives me a much more reasonable looking port length of 80mm so not far off your calculations.

 

I've started chopping wood - the idea is to make something with the same volume and driver as this but in a slightly different shape that fits in a bag I've got, so I can wheel the double bass along with this on my back. So I wanted to have it in WinISD in case I needed to change the port shape or mess something up and get a different internal volume.

 

Cheers!

[Pea Turgh]

43 minutes ago, cbd said:

Thanks for checking those - unfortunately re-inputting the parameters didn't help but tuning to 87Hz gives me a much more reasonable looking port length of 80mm so not far off your calculations.

 

I've started chopping wood - the idea is to make something with the same volume and driver as this but in a slightly different shape that fits in a bag I've got, so I can wheel the double bass along with this on my back. So I wanted to have it in WinISD in case I needed to change the port shape or mess something up and get a different internal volume.

 

Cheers!

 

Keep us up to date with your progress- love a build diary!

[tauzero]

A short cautionary tale - I've used the cab several times with a Tecamp Puma 900 with no problems. Went to an open mic night on Wednesday and the organiser asked if some lads could borrow it. I said yes as long as they didn't mess with the gain and volume, and set them a bit lower than I use myself. They were guitar with a 2x12 combo, electronic drums, and bass. They did 3 numbers, came off for a bit, then went back on, and after a couple of numbers I could hear the cab was cutting out and then went silent. I think the cause of death was blunt instrument trauma rather than stabbing, pounding semiquavers had pushed the speaker into thermal failure - my own bass style might be busy but it's not incessant. The bassist was very apologetic. Got it home, opened the back, smelled the fumes, checked impedance (open circuit), ordered another speaker. It's now back together and running, I've decided to get a smaller amp to use with that cab and to use the Plenty 1x10 as a minimum with the Tecamp from now on. 

[Geek99]

On 02/09/2024 at 12:14, rwillett said:

 

It doesn't say it makes an excellent job of finishing speaker cabs on the tin though....

It’s probably shit I mean “unsuitable” then. But it works.

What a dichotomy advertising has brought us to …

[cbd]

On 04/12/2024 at 13:16, Pea Turgh said:

 

Keep us up to date with your progress- love a build diary!

Of course - here you go:

 

[Phil Starr]

On 14/12/2024 at 00:21, tauzero said:

A short cautionary tale - I've used the cab several times with a Tecamp Puma 900 with no problems. Went to an open mic night on Wednesday and the organiser asked if some lads could borrow it. I said yes as long as they didn't mess with the gain and volume, and set them a bit lower than I use myself. They were guitar with a 2x12 combo, electronic drums, and bass. They did 3 numbers, came off for a bit, then went back on, and after a couple of numbers I could hear the cab was cutting out and then went silent. I think the cause of death was blunt instrument trauma rather than stabbing, pounding semiquavers had pushed the speaker into thermal failure - my own bass style might be busy but it's not incessant. The bassist was very apologetic. Got it home, opened the back, smelled the fumes, checked impedance (open circuit), ordered another speaker. It's now back together and running, I've decided to get a smaller amp to use with that cab and to use the Plenty 1x10 as a minimum with the Tecamp from now on. 

 

The problem was probably excessive excursion. The cab is an awful lot safer with those sort of powers if you use an HPF at 50Hz or even higher.  The output is very limited below 80Hz by design so there's no point letting anything through below that.  The coil may have been smacking against the back of the magnet and if it over excurts (is that a word?) it loses the cooling effect of being in the magnetic gap. If i'm playing that loud I pretty much always put the cab right in a corner and roll off the bass which corner placing reinforces. I'm glad it's mended, the BAM will be a perfect match and does have some bass roll off built in which helps.

[cbd]

Is there any benefit to putting a capacitor in series with the speaker as a crude high pass filter? Just had a go on a crossover calculator website which reckons a 220uf bipolar would give you a 6db/octave cutoff at around 90Hz - that would cost about £2.50. Or would it have to be steeper than that to avoid taking too much off the higher frequencies?

[Woodwind]

26 minutes ago, cbd said:

Is there any benefit to putting a capacitor in series with the speaker as a crude high pass filter? Just had a go on a crossover calculator website which reckons a 220uf bipolar would give you a 6db/octave cutoff at around 90Hz - that would cost about £2.50. Or would it have to be steeper than that to avoid taking too much off the higher frequencies?

 

It's a very good question, but I suspect it would be a better solution (and sadly more expensive) to add a dedicated high pass filter (like a thumpinator or Fdek) in line with the instrument.