New BassChat 8"Cab design

[Phil Starr]

It's never a bad thing to seal up the cab. I usually use draughtproofing foam strip to seal my connector plates and the baffles and rear panels which on my personal cabs are just screwed and not glued. 

 

Interestingly some allowance for leakage is made when calculating the cab sizes and tuning Using a factor called Ql. WinISD defaults to Ql=7 which is what I've always done anyway and by and large the measurements on the cab come out very close to those expected. You can't seal everything and the magnetic gap in the speaker itself is almost always open but sealing things where you can is good.

[Obrienp]

It will help prevent rattles as well, if there is no gasket supplied with the plate.

 

Please could you share your wiring diagram for the speakon sockets please. I have no idea how to wire them together so that you can daisy chain cabs.

[tauzero]

Connect the two 1+ together and the two 1- together. Connect the 1+ to the +/red of the speaker and 1- to the -/black.

 

And I use thin neoprene draught proofing strip. Unfortunately I've bought both 1mm thick and 3mm thick so I don't know which one I used on my previous builds, but it was 10mm wide.

[Stub Mandrel]

It's best to minimise leakage, but most have some porosity around the connectors, especially if using jack sockets.

 

If you use a vinyl covering then the edges will seal well enough, but if on a hard surface a bit of sealant wouldn't be a bad idea.
 

[rwillett]

@Stub Mandrel

 

I'll try and make gaskets for the jack sockets and for the plate. That would be neater than sealant, which knowing my luck, would mean I'd attach myself to the cabinet, never to be released. Much like Hans Solo in his Carbon tomb .

 

Rob

[Phil Starr]

If it helps this is the back of the Speakon sockets. They are neatly marked as +1 and -1 the +1 is connected to the +1 on the second socket and then to the + or red terminal on the speaker.

 

If you use a jack socket then you are very naughty, but the tip of the jack is the +1 and the sleeve is the -1. 

 

[Phil Starr]

It's also just possible to use spade terminals which crimp to the wires without soldering, though I recommend soldering if you can do it. 

 

 

[Stub Mandrel]

1 hour ago, Phil Starr said:

It's also just possible to use spade terminals which crimp to the wires without soldering, though I recommend soldering if you can do it. 

 

 

 

In practice, well-made spade connections are more reliable. A proper crimp tool causes cold-welding, there is better strain relief, and a little spring bit on the spade engages the hole in the tab so it can't vibrate loose.

 

It's been widely demonstrated that soldering wires to crimp connectors decreases their fatigue life.

 

Thus is why crimps are ubiquitous for automotive and aetospace applications. 

 

[Chienmortbb]

  The problem with crimp, especially those Faston crimps, is that they vary in quality. Some are too tight to fit on the blade and others are just too loose. At the speaker end, the issue is more that it is hard to keep the soldering iron away from the magnet.

 

As for sealing the speakons, the speakons themselves usually form a reasonable seal with the panel. Jacks are a different matter. There are very few jacks that are sealed, and I once borrowed a cab the kept whistling. Of course, we all like a happy cabinet, but it was disturbing. The temporary solution was to put a jack plug into the unused socket. The long term solution, if you MUST use a jack plug, is to use the Cliff S1K Sealed Jacks. These can be purchased from RS, Cliff sealed jacks.  Here is the PDF of the range. Cliff Data Sheet

 

It should be remembered that these are rated at 5 amps. So 200 Watts into 8 ohms or 125 Watts into 4 ohms. OK for gig bag amps lie the Elf and Gnome but anything else use speakons. 

 

 

 

 

[Stub Mandrel]

 

 

[tauzero]

I use the combo speakon/jack sockets, so I can swing either way.

[rwillett]

These are the Speakon connectors soldered up and ready to go. I have to confess I brought them with the PCB but I did make a rubber gasket for each of the Speakon adaptors and soldered it all up.

 

 

 

 

I'll use foam strip around the edges once I've made a hole in the back of the speakers to fit this. I may get the chance tomorrow but the nights are drawing in and it's circa 1C at the moment and I hate working outside in the freezing cold.

Rob

[Richard R]

Using jacks for cabinets is a terrible idea, as this photo clearly shows:

 

 

 

[rwillett]

America says "hold my (wishy washy) beer"

 

[Chienmortbb]

13 hours ago, tauzero said:

I use the combo speakon/jack sockets, so I can swing either way.

Twas always suspected!

[Chienmortbb]

38 minutes ago, rwillett said:

America says "hold my (wishy washy) beer"

 

Not a trace of flavourwois be lost if that roof fell. 

[Chienmortbb]

10 hours ago, Richard R said:

Using jacks for cabinets is a terrible idea, as this photo clearly shows:

 

 

 

I am not sure this are 8” cabinets. 

[rwillett]

Just in case anybody is interested, I've designed and printed a complete port and flange for my 8" speaker.

 

Its the correct length, 87mm, and is 64mm internal diameter and fits a 68mm hole. It has three M3 screw holes and the actual flange is sized so you can put M3 T-Nuts behind it and so they don't overlap the hole.

 

It has a gasket groove on the back , so you can put 2mm x 10mm foam around the back of the flange, and when you tighten the screws up, it sits flush to the baffle board, but you now have a better seal. Especially useful if you port hole is a bit rough. 

 

It has simple text on the front, but I change that easily.

 

I can print them in a variety of colours, but red is very popular at the moment as I still have 27 reels to go through  

 

I'll print them for free, I'll include some foam for the gasket, just pay for postage and a appropriate donation to the North West Air Ambulance of whatever you want to pay. I'd prefer it to be more than 1p but I won't check.

 

I can adjust most things quite quickly and easily so if you wanted your name on them, or a different size or whatever just ask. 

 

 

Different colours can be done but only if I have those colours sitting on the shelf.

 

Thanks

Rob

[Bassybert]

1 hour ago, rwillett said:

Just in case anybody is interested, I've designed and printed a complete port and flange for my 8" speaker.

 

Its the correct length, 87mm, and is 64mm internal diameter and fits a 68mm hole. It has three M3 screw holes and the actual flange is sized so you can put M3 T-Nuts behind it and so they don't overlap the hole.

 

It has a gasket groove on the back , so you can put 2mm x 10mm foam around the back of the flange, and when you tighten the screws up, it sits flush to the baffle board, but you now have a better seal. Especially useful if you port hole is a bit rough. 

 

It has simple text on the front, but I change that easily.

 

I can print them in a variety of colours, but red is very popular at the moment as I still have 27 reels to go through  

 

I'll print them for free, I'll include some foam for the gasket, just pay for postage and a appropriate donation to the North West Air Ambulance of whatever you want to pay. I'd prefer it to be more than 1p but I won't check.

 

I can adjust most things quite quickly and easily so if you wanted your name on them, or a different size or whatever just ask. 

 

 

Different colours can be done but only if I have those colours sitting on the shelf.

 

Thanks

Rob

 

I'd like one please Rob, looks great and more than happy to make a donation for it ☺️

[rwillett]

1 hour ago, Bassybert said:

 

I'd like one please Rob, looks great and more than happy to make a donation for it ☺️

 

DM'ed you.

[Pea Turgh]

Did anybody proceed with a 2x8 version? Not even finished my 12” and already getting the measuring tape out for another build!

[basstone]

I fancy having a go with a monitor style cab with the back corners at 45 degrees.  I’d make the cab a bit wider and deeper to keep the same internal volume and match the form factor of a 10” cab I have

[Phil Starr]

46 minutes ago, Pea Turgh said:

Did anybody proceed with a 2x8 version? Not even finished my 12” and already getting the measuring tape out for another build!

I've got a spare set of panels and a speaker. I was going to build and document the build sometime soon so I'll have a pair of these. I'm also happy to design a 2x8 for anybody who wants a go at building one. (this is where I'm tryiong to remember if I've already done this design for anyone)

[Pea Turgh]

Just sketched out something that will be equal to two 1x8s stacked on landscape.  Me likey.  I was just going to make it with those dimensions and put two ports in.  I would welcome your input though @Phil Starr!