1x12" Cab Design Diary

[Phil Starr]

[quote name='owen' timestamp='1413802394' post='2581978']
[url="http://www.hypex.nl/product/2012-11-23-13-44-01/2012-11-23-13-46-04/psc2-700.html"]http://www.hypex.nl/...4/psc2-700.html[/url]
[/quote]

Trouble is they are quoting 460 Euros, you could buy an RCF PA speaker with the speakers and cab for that. Shame as it would be a great thing to use something that flexible.

[Chienmortbb]

Hypex are very good but very expensive. The miniDSP plate amps at [url="http://www.minidsp.com/products/plate-amplifiers"]http://www.minidsp.com/products/plate-amplifiers [/url]
are worth a look and are good value for the ICEpower modules versions. I still question whether a plate amp is a good idea in a bass oriented cab though.

My worry is that Powered PA cabs rarely go very low (forget the sales specs, there will be little below 100Hz) so the main problem is heat. Putting an amp in a bass cab is like running it permanently on a vibration test.

Edited October 21, 2014 by Chienmortbb

[LukeFRC]

[quote name='Chienmortbb' timestamp='1413908837' post='2583484']
Hypex are very good but very expensive. The miniDSP plate amps at [url="http://www.minidsp.com/products/plate-amplifiers"]http://www.minidsp.com/products/plate-amplifiers [/url]
are worth a look and are good value for the ICEpower modules versions. I still question whether a plate amp is a good idea in a bass oriented cab though.

My worry is that Powered PA cabs rarely go very low (forget the sales specs, there will be little below 100Hz) so the main problem is heat. Putting an amp in a bass cab is like running it permanently on a vibration test.
[/quote] Powered PA subs manage it though.

[Chienmortbb]

True. I was trauned in Military Elevtronics and vibration testing was a big part of the QC regime.

So tne three things against plate anps, heat, vibration and pneumatic integrity of the caninet makee wary of powered bass cabs.

If you do go witn a plate amp I suggest an ICE power one as they really are road tested.

[LukeFRC]

hey there! rescuing this from the second page... also pointing out that if you go into the TKS sub forum and look at their ex trial speakers threads they've got 4 of the Beyma drivers that the 3 musketeers are using...

[Chienmortbb]

[quote name='LukeFRC' timestamp='1415346050' post='2599350']
hey there! rescuing this from the second page... also pointing out that if you go into the TKS sub forum and look at their ex trial speakers threads they've got 4 of the Beyma drivers that the 3 musketeers are using...
[/quote]SubsonicSimpleton(Andy) and I eould like one each and if anyome else is interested please PM Me or SubsonicSimpleton.

[Ghost_Bass]

Any news on the cabs? Photos, specs, plans, etc.? I'm looking forward to have a crack at building one for myself. Do they have a name, brand? Maybe a logo contest to keep us busy

[6v6]

[quote name='Ghost_Bass' timestamp='1415791729' post='2603753']
Any news on the cabs? Photos, specs, plans, etc.? I'm looking forward to have a crack at building one for myself. Do they have a name, brand? Maybe a logo contest to keep us busy
[/quote]

If you're keen to get going, you could refer to my build diary, which includes dimensions for a cab built around the same driver (Beyma SM212).

http://basschat.co.uk/topic/200152-1x12-diy-cab-build

I can't claim anything like the expertise of the folks driving this thread (I got a lot of help from Phill Starr working out my design) but I've been gigging the cab for a year and it works very well.

[Phil Starr]

Just a thought but if anyone is in the Sidmouth area tonight I'll be playing (badly) through the prototypes if you fancy a look/listen/try http://www.lemonrock.com/gig.php?id=368248 7.30 onwards

[tauzero]

How close are you to publishing the design now?

[Phil Starr]

Just got back from gigging. The design is finished really though I'd like someone else to try it out and give a second opinion. All I have to do now is to build the final box, photograph the process then turn it into a set of instructions that anyone can follow, preferably with a set of drawings too.

I'll set my mind to it next week.

Good gig though, really good fun.

[Thunderpaws]

Hello Phil.

Are you producing the drawings on CAD? If not, I can have a bash for you when you have dimensions. Using Autodesk Inventor.

[LukeFRC]

if you need any layout help making a nice PDF I can stick on my graphic designers hat for you.

[Phil Starr]

Thanks guys, I might take you up on that, The plan is for one of the other guys to do that from my sketches but they may well appreciate someone else taking that on. I'm still a paper and pencil/back of an envelope guy. I'll ask Lawrence.

Biggest hold up now is getting another bass player or two to try the cabs, I'm gigging them so I don't want to send them off to someone and I live in the middle of nowhere so there aren't too many people around within 20 miles of me.

[MoonBassAlpha]

Were there people around you BEFORE you embarked on bass cab building?

[Phil Starr]

[quote name='MoonBassAlpha' timestamp='1417094278' post='2617025']
Were there people around you BEFORE you embarked on bass cab building?
[/quote]

Just Leo Fender!

[Beer of the Bass]

I've been pondering my gear needs and having a look over this thread. Currently I have a 2x12" cab loaded with a pair of 4-ohm B&C 12HPL64 drivers, wired in series for 8 ohms. This has good sensitivity and gets plenty loud enough for my needs even with moderately powered amps. The lows aren't massive on paper (it's 3dB down at around 75Hz), but in practice they're more than sufficient and I often roll off the bass EQ on the amp. It's a very light cab for its size and capabilities, but I think that most of what I do could be covered with a 1x12", occasionally adding a second one where needed. Portability is very important to me, as I live upstairs in a city centre flat. With that in mind, I've been looking at a few different options for one or two smaller cabs and comparing the specs against my current 2x12". In terms of tone, I don't need or want highs in the tweeter region but I like to hear plenty of upper mid, and I'm not bothered with trying to produce the lowest fundamentals.
With that as background, would it be a crazy idea to think about reducing the volume of the cab using the SM212? Playing around with WinISD, reducing the volume to around 35-40 litres gives a midbass bump of just over 1dB (depending on tuning). Having played cabs with larger bumps, I feel that could be workable. Using the same volume but plugging the ports for a sealed design gives the expected smooth roll-off, but the maximum SPL of a pair of them is still very close to my existing 2x12" which has always been enough for me. It wouldn't be too hard to build one and try it both ways. Obviously these would be a compromise compared to the 50 litre design presented here, but it seems this could be an acceptable trade-off for my particular needs.

[Chienmortbb]

A one dB hump is nothing. 1dB is what is known in engineering terms as a JND or just noticeable difference. However that is in controlled conditions where Ambient noise is low and controlled. I don't know if any musical performs fe where that is the case.

In normal use no one can hear 1dB.

Edited December 18, 2014 by Chienmortbb

[Phil Starr]

[quote name='Beer of the Bass' timestamp='1418907073' post='2634677']
I've been pondering my gear needs and having a look over this thread. Currently I have a 2x12" cab loaded with a pair of 4-ohm B&C 12HPL64 drivers, wired in series for 8 ohms. This has good sensitivity and gets plenty loud enough for my needs even with moderately powered amps. The lows aren't massive on paper (it's 3dB down at around 75Hz), but in practice they're more than sufficient and I often roll off the bass EQ on the amp. It's a very light cab for its size and capabilities, but I think that most of what I do could be covered with a 1x12", occasionally adding a second one where needed. Portability is very important to me, as I live upstairs in a city centre flat. With that in mind, I've been looking at a few different options for one or two smaller cabs and comparing the specs against my current 2x12". In terms of tone, I don't need or want highs in the tweeter region but I like to hear plenty of upper mid, and I'm not bothered with trying to produce the lowest fundamentals.
With that as background, would it be a crazy idea to think about reducing the volume of the cab using the SM212? Playing around with WinISD, reducing the volume to around 35-40 litres gives a midbass bump of just over 1dB (depending on tuning). Having played cabs with larger bumps, I feel that could be workable. Using the same volume but plugging the ports for a sealed design gives the expected smooth roll-off, but the maximum SPL of a pair of them is still very close to my existing 2x12" which has always been enough for me. It wouldn't be too hard to build one and try it both ways. Obviously these would be a compromise compared to the 50 litre design presented here, but it seems this could be an acceptable trade-off for my particular needs.
[/quote]

B & C drivers are as good as pretty much anything out there, so why not just try them in the smaller cab. I'm just having lunch so all I've done is look at the T/S parameters but I think they'd behave better in the 35l cab than the SM212's. Qts and Vas are lower than the SM212 which helps. Xmax for the SM212 is better and the frequency response is flatter but the response peak in the B&C is probably much better for a bass. The only problem I can see is that a single one would be 4 ohms and you'd need to wire one of the cabs so you could get a series connection to use them as a pair, they are Neo too so there's a weight saving, nice drivers.

[Beer of the Bass]

[quote name='Phil Starr' timestamp='1418915857' post='2634811']
B & C drivers are as good as pretty much anything out there, so why not just try them in the smaller cab. I'm just having lunch so all I've done is look at the T/S parameters but I think they'd behave better in the 35l cab than the SM212's. Qts and Vas are lower than the SM212 which helps. Xmax for the SM212 is better and the frequency response is flatter but the response peak in the B&C is probably much better for a bass. The only problem I can see is that a single one would be 4 ohms and you'd need to wire one of the cabs so you could get a series connection to use them as a pair, they are Neo too so there's a weight saving, nice drivers.
[/quote]

Yes, the 4 ohm impedance is the only thing putting me off doing that, as the B&Cs are good sounding drivers and it's possible that with a flatter driver I'd miss the upper mid peak that they have. If I can come up with an elegant way to achieve the series connection with two separate boxes that may not be a bad idea.

[Phil Starr]

It's simple to wire with switched jack sockets, just wire the sockets in series so they short when the plug is pulled out.

[Beer of the Bass]

[quote name='Phil Starr' timestamp='1418922236' post='2634932']
It's simple to wire with switched jack sockets, just wire the sockets in series so they short when the plug is pulled out.
[/quote]

That's true. I'd been a bit stumped trying to figure out a way to do it with speakons, but using jacks wouldn't be a big deal. Are switched jacks trustworthy with speaker level signals? I've never checked whether they have a current rating.

[Passinwind]

[quote name='Beer of the Bass' timestamp='1418923325' post='2634944']
That's true. I'd been a bit stumped trying to figure out a way to do it with speakons, but using jacks wouldn't be a big deal. Are switched jacks trustworthy with speaker level signals? I've never checked whether they have a current rating.
[/quote]

Switched Speakons exist, never seen one in the flesh though.

[dincz]

[quote name='Passinwind' timestamp='1418924001' post='2634948']
Switched Speakons exist, never seen one in the flesh though.
[/quote]

Interesting. I just took a look and apparently they aren't airtight

http://www.neutrik.com/en/speakon/speakon-chassis-connectors/nl4md-v-s

Edited December 18, 2014 by dincz

[Passinwind]

[quote name='dincz' timestamp='1418932618' post='2635035']
Interesting. I just took a look and apparently they aren't airtight

[url="http://www.neutrik.com/en/speakon/speakon-chassis-connectors/nl4md-v-s"]http://www.neutrik.c...ctors/nl4md-v-s[/url]
[/quote]

Bummer. They're probably intended for patch bays in pro sound amp racks. I've made RTV sealant work adequately with other unsealed panel mount Speakons, but those things will whistle like crazy in a bass cab if you don't figure something out.