Basschat 2x12

[JPJ]

Like a lot of us, I followed the design mega thread of the Basschat 1x12 with great interest (and the simpler version too). I am thinking of building one, but I really fancy a 2x12. My question to @stevieand @Phil Starr is would it simply be a case of doubling the cab size to add a second 12” driver (even in a divided box if necessary)?

[warwickhunt]

What (if any) advantage would a 2x12 give over a pair of 1x12s?  You could always take a single 12 to rehearsals etc and double up for 'proper' gigs. 

 

With regards to carrying a cab(s); a 212 would necessitate 1 trip whereas a pair of 112 would equally be 1 trip... no gain?

 

If the 2x12 was a 4 ohm cab to get the max from a regular amp, you'd be unlikely to add another cab to the 2x12?  

 

I only pose the questions as I've owned 212s (Bergantino and Aguilar) and there was no discernible benefit over the pairs of 112s I've had by the same manufacturers.  

[JPJ]

18 minutes ago, warwickhunt said:

What (if any) advantage would a 2x12 give over a pair of 1x12s?  You could always take a single 12 to rehearsals etc and double up for 'proper' gigs. 

 

With regards to carrying a cab(s); a 212 would necessitate 1 trip whereas a pair of 112 would equally be 1 trip... no gain?

 

If the 2x12 was a 4 ohm cab to get the max from a regular amp, you'd be unlikely to add another cab to the 2x12?  

 

I only pose the questions as I've owned 212s (Bergantino and Aguilar) and there was no discernible benefit over the pairs of 112s I've had by the same manufacturers.  

 

Good point well made. I suppose I just fancy a single 4ohm cab solution. Also, in my head the second 1x12 could be simpler (no crossover or compression driver).

[Phil Starr]

Hi, I've been wondering about adding to the designs and publishing them here. I thought a 2x10 or a 15 would be next though we did briefly discuss a simple build 1x12T along the lines of our 110T. The biggest problem is not the design but because all our speakers are built then proper testing and measurement is followed by extensive gigging before we recommend them. It's the testing and development that takes the time.

 

Maybe we could do something different and design a 2x12 for you and ask you to document the build. We could then get proper drawings done and others could copy the build. That is assuming you just want a straight 12 with no horn and crossover which we couldn't do without testing and measurement.

 

Would you be up for that?

[JPJ]

8 hours ago, Phil Starr said:

Hi, I've been wondering about adding to the designs and publishing them here. I thought a 2x10 or a 15 would be next though we did briefly discuss a simple build 1x12T along the lines of our 110T. The biggest problem is not the design but because all our speakers are built then proper testing and measurement is followed by extensive gigging before we recommend them. It's the testing and development that takes the time.

 

Maybe we could do something different and design a 2x12 for you and ask you to document the build. We could then get proper drawings done and others could copy the build. That is assuming you just want a straight 12 with no horn and crossover which we couldn't do without testing and measurement.

 

Would you be up for that?

Hi Phil,

 

I’d definitely be up for that. Something fairly efficient, and don’t worry about complexity, I’m a fairly competent wood butcher. Oh and a slot port please. Oh and 19” wide as I can’t stand overhanging amps 😂

 

At todays rehearsal I got to use a wonderful old Carlsbro Stingray Pro Bass 4x12 which must have been a very efficient design as it was monsterously loud with the master volume barely on. 

[Phil Starr]

OK that's a good starting point, I'm guessing lightweight is not an issue then

 

Those Carlsbro's probably have high efficiency as they have short throw speakers and of course lots of them. You won't get that out of a 2x12 and modern drivers without going for something with short voice coils and restricted power handling as a result. So what sort of an amp would you be going for? Am I designing for a 100W valve amp or a 5-800W classD? (I'm picturing a 500W class A/B from the 19" spec) How are you going to use the speaker? All purpose gigging speaker, with or without PA support, All the bass coming from the backline with John Bonham and Keith Moon doubling up on drums? What sort of tone are you after is another issue too.

 

Finally the big one. What's the budget?

[JPJ]

19 minutes ago, Phil Starr said:

OK that's a good starting point, I'm guessing lightweight is not an issue then

 

Those Carlsbro's probably have high efficiency as they have short throw speakers and of course lots of them. You won't get that out of a 2x12 and modern drivers without going for something with short voice coils and restricted power handling as a result. So what sort of an amp would you be going for? Am I designing for a 100W valve amp or a 5-800W classD? (I'm picturing a 500W class A/B from the 19" spec) How are you going to use the speaker? All purpose gigging speaker, with or without PA support, All the bass coming from the backline with John Bonham and Keith Moon doubling up on drums? What sort of tone are you after is another issue too.

 

Finally the big one. What's the budget?

So the cab would be used in both scenarios, as completely standalone bass reproduction in smaller pub gigs and with PA support on larger stages. Amp-wise my current stable contains the Ashdown Head of Doom (shown in the picture), a pre/power setup containing the SWR Marcus Miller pre coupled with their 400W class D Amplite power amp, and the 1500w behemoth SWR SM1500.

Primary design objective will not be weight, and I’m not against fitting wheels and a handle to trundle it around. My current ‘go to’ cab is an SWR Goliath II fitted with Eminence Deltalite speakers. This cab does all my gigs both with and without PA support. As I said earlier, I’m a fairly competent wood butcher so you can get creative (top and bottom shelf ports, centre port, three shelf ports, drivers in their own boxes, folded horn, or split angled baffle a la early Schroeder cabs). Budget-wise, I’m fairly flexible but why don’t we say up to £500 for the two drivers I.e around 50% of the as new price of a Barefaced Super Twin?

[Phil Starr]

OK That's helpful, I'd identified the Deltalites as a possibility  So are you looking to beat the SWR or just for something different? £250 per driver is a top price for a 12 so you'd have a wide choice

 

[JPJ]

‘Beat’ is an emotive term isn’t it. I play a lot of five string bass so low (or pseudo low) end is important. I’m not a slap pop & tapper and mainly play what you might call classic rock, southern rock, and country style music. I like a little mid growl but certainly don’t need glassy highs. 
 

I originally thought this might be as simple as building two Basschat 1x12 mk II’s, leaving the compression driver and crossover out of one and metaphorically gluing them together 😂 - shows how much I know about loudspeaker design 😂

[Phil Starr]

That would work to give you the deep bass but you'd be a bit limited by the power handling of the compression driver of the horn and you'd have to consider how the crossover would work. It would handle the crossover to one bass driver only. You could wire it that way but then the mids from the second driver would interfere with the output from the horn. None of this would be a disaster necessarily and it's something many people have tried with other speakers and been happy with. You were right in assuming you could just put two speakers in a double sized box btw though you/I would have to recalculate the port size. To be fair a couple of us in the design team were looking to try running a mk2 (tweetered) on top of a Mk1 including me so I obviously didn't think it daft. The bass you get from two SM212's is extraordinary but they are a bit dark without any tweeter.

 

'Beat' was only something I used because the Deltalites are a nice speaker and 'only' cost £134 at the moment comparable with the £139 for the Faital 320 which we used in the Mk 3. There's no point in spending £500 unless you get an advantage over spending £268 on the Delta's. Of course 'advantage' is another subjective word. So I guess what I'm trying to find out is what you expect to gain.

 

The Beyma SM212 has been discontinued despite my contacting Beyma directly but Blue Aran bought up their remaining stock and they still have a few left. The SM212 does have an advantage in low power handling/excursion over anything else at that price but if you wanted to go that route you'd need to buy them before BA sell out.

 

Are you in a rush? I'm not going to have much time this week but I'll offer you a few options as soon as I have time to model them.

[JPJ]

Thanks again Phil, I’m in no particular rush and happy to be the Basschat test pilot

[Stub Mandrel]

comment so this is in my feed!

[Phil Starr]

OK this is the frequency plot for 4 speakers. The Kappalite used by Barefaced (red) Beyma Sm212 (blue) Deltalite (purple) and the Faital 320 (green) all in the same cabinet 50litres. You know what the Deltalite's sound like so that gives you a starting point. They have a peak around 120Hz of about 2db which is colouring the bass and the bass rolls off slowly from there. The Beyma has a similar peak slightly les high than the Delta's but has the highest output at 40Hz of all the speakers. The FAital has the highest peak of all, around 3db and the highest output between 50-100Hz. the interesting one is the Kappalite with the most powerful magnet it has the flattest response down to 70Hz and then rolls off more quickly that the other speakers. Remember this is just the bass response up to 200Hz so not the whole picture.

 

Remember these are all in the same box, they can all be put in different boxes, the beyma would love a larger box and the Kappa would be better in a smaller box, or i can tune the boxes differently and shape the curves a little. Despite this I think it is fair to say the Beyma is going to have the deepest bass and the Kappa is going to be the most honest speaker with all the rest tending towards warm sounding.

[JPJ]

Cheers Phil, that’s very interesting and makes a lot of sense. When I put the Deltalites in the 4x10 Goliath it definitely acquired a very ‘musical’ low mid bump compared to the tired old PAS speakers. Daft question, but is there any advantage to mixing drivers albeit in separate boxes or is that a big no no?

[Marty Forrer]

I built my own 2x12 and it is great! It weighs 18kg and has tiltback handle and recessed wheels as well as side handles. Drivers are Gallien Krueger Neo 12s @ 300w each. No crossover or horn (I always turn them off anyway). I made the outside dimensions the same as a Barefaced SuperTwin and the port size I just winged it. It handles a low B string perfectly, so I guess I lucked in. Material was 1/2" Oukume ply with Duratex coating. Since these pics I changed to Speakon connectors.

 

Edited July 22, 2022 by Marty Forrer

[Phil Starr]

6 hours ago, JPJ said:

Cheers Phil, that’s very interesting and makes a lot of sense. When I put the Deltalites in the 4x10 Goliath it definitely acquired a very ‘musical’ low mid bump compared to the tired old PAS speakers. Daft question, but is there any advantage to mixing drivers albeit in separate boxes or is that a big no no?

Mixing speakers is a bit of a lottery. No speaker is truly flat and the character or timbre is a result of all the lumps and bumps in the response. With two speakers the peaks won't line up and the combination will create a completely different set of highs and lows. You'll lose the character of both speakers. On top of that you'd have to match sensitivity and speakers have to be matched to the box so you'd need two boxes.

[Phil Starr]

This is where it gets interesting. This shows the maximum output the speakers can make. All of them have a dip centred around 80Hz. This is normal and is due to excursion limits. The speaker has to move further for low frequencies and below 50Hz none of them can manage the excursion. At 60Hz the port is making most of the sound and the speaker movement is damped by the port so they can all do their thing. At low levels over-excursion just manifests itself as distortion, at high levels it can destroy the speaker or lead to the coil overheating and reduced output or power compression. Over excursion reduces the power handling of the speaker.

 

The Kappa comes out best with only a tiny dip which would be inaudible, The Deltalites have a significant dip of over 6db and the power handling before distortion drops to 60W. The dips in the other two aren't anything I would worry about  but the Kappa is definitely going to give the tightest sound in this box. The Beyma is the strange one as it is 6db louder at 40Hz than the others in this box.

 

I don't think a 40Hz output is musically useful in a bass speaker. our hearing down there isn't very good but it can excite room resonances and muffle the bass. In a band setting I prefer those frequencies to be left to the drums with the bass filling the gap between kick and the other instruments. If I'm mixing and the desk allows it I'll filter the bass at 50hz and my ideal sound is flat between 80-160Hz. If I'm designing a small speaker I do design in that extra warmth a mid-bass hump gives to compensate for the lack of bottom end. In listening tests most bassists however seem to like the warm bloom in their sound. It's a bit marmite though, you love it or hate it.

 

At this point then it's a matter of taste. For me at this budget point I'd go for the Kappa, The UK prices for Eminence speakers has recently improved so they are competitive again. I like a tight articulate bass sound and would roll off the bass at the lowest frequencies anyway. However it is a matter of taste not right or wrong. The other thing is that of these speakers all but the SM212 have a midrange peak that livens up the sound of a single driver, effectively the Delta and the Faital have a mid-scoop, the result of that low hump in the bass and the mid peak. They sound like a bass speaker. The SM212 has a flat but extended mid/top and sounds more neutral. I gigged with it for years and you just have to eq differently but I've moved on to cabs with horns and I'm happier with that.

 

So you have lots of options but the first choice is nice warm old school or tight and articulate bass. 

[RichardH]

At the moment I am borrowing a cab From Stevie - it is a tweaked version of the Basschat 112 - the driver in it is stupendous. I used to have a GK NEOX 212. I reckon this 1x12 could keep up with it. Played a pub gig with it a couple of weeks ago and had my amp (Genzler Magellan 800) on about 9 o'clock - PA was only for vox and guitars. It has made me realise that I very much doubt I need more than a similarly potent 1x12!

 

Edited July 22, 2022 by RichardH

[GlamBass74]

Having used SM212's for gigging for a few years now (50L / 50hz) I opted to try the SM212 in a 70L nett enclosure tuned to 47hz

 

I'd originally planned to use it as a compact sub for a band PA system, but playing bass through it really impressed me! (i like to feel my bass 😁)

 

I will do a bit of a write up once I get it finished off

 

[JPJ]

6 hours ago, Phil Starr said:

This is where it gets interesting. This shows the maximum output the speakers can make. All of them have a dip centred around 80Hz. This is normal and is due to excursion limits. The speaker has to move further for low frequencies and below 50Hz none of them can manage the excursion. At 60Hz the port is making most of the sound and the speaker movement is damped by the port so they can all do their thing. At low levels over-excursion just manifests itself as distortion, at high levels it can destroy the speaker or lead to the coil overheating and reduced output or power compression. Over excursion reduces the power handling of the speaker.

 

The Kappa comes out best with only a tiny dip which would be inaudible, The Deltalites have a significant dip of over 6db and the power handling before distortion drops to 60W. The dips in the other two aren't anything I would worry about  but the Kappa is definitely going to give the tightest sound in this box. The Beyma is the strange one as it is 6db louder at 40Hz than the others in this box.

 

I don't think a 40Hz output is musically useful in a bass speaker. our hearing down there isn't very good but it can excite room resonances and muffle the bass. In a band setting I prefer those frequencies to be left to the drums with the bass filling the gap between kick and the other instruments. If I'm mixing and the desk allows it I'll filter the bass at 50hz and my ideal sound is flat between 80-160Hz. If I'm designing a small speaker I do design in that extra warmth a mid-bass hump gives to compensate for the lack of bottom end. In listening tests most bassists however seem to like the warm bloom in their sound. It's a bit marmite though, you love it or hate it.

 

At this point then it's a matter of taste. For me at this budget point I'd go for the Kappa, The UK prices for Eminence speakers has recently improved so they are competitive again. I like a tight articulate bass sound and would roll off the bass at the lowest frequencies anyway. However it is a matter of taste not right or wrong. The other thing is that of these speakers all but the SM212 have a midrange peak that livens up the sound of a single driver, effectively the Delta and the Faital have a mid-scoop, the result of that low hump in the bass and the mid peak. They sound like a bass speaker. The SM212 has a flat but extended mid/top and sounds more neutral. I gigged with it for years and you just have to eq differently but I've moved on to cabs with horns and I'm happier with that.

 

So you have lots of options but the first choice is nice warm old school or tight and articulate bass. 

I 'think' I prefer nice warm old school to be honest. I notice most commercial 2x12's seem to calculate to around 110-120 litres so I'm guessing that's 50-60 litres per driver?

[Phil Starr]

3 minutes ago, JPJ said:

I 'think' I prefer nice warm old school to be honest. I notice most commercial 2x12's seem to calculate to around 110-120 litres so I'm guessing that's 50-60 litres per driver?

 

OK that's good, I'd have gone for the Kappalite's myself. So we've eliminated them. Although I could force a hump into the response by reducing the size of the cab.

 

If you want full on bass and not too much else you could go for the Beyma's if you are quick as there are still a few available but the Faital 320's are great speakers and have that upper midrange lift of an old school speaker, well within your budget and lightweight too. I'm not sure if @RichardH has the same speaker I have at the moment but mine has the the Faital and one on its own gives you a real punch in the stomach. I'll have a better look at that and see what I come up with. 

 

[RichardH]

19 minutes ago, Phil Starr said:

 

I'm not sure if @RichardH has the same speaker I have at the moment but mine has the the Faital and one on its own gives you a real punch in the stomach. I'll have a better look at that and see what I come up with. 

 

 

No, it's actually a non-neo driver - I don't know the exact driver - though he did say it's a discontinued driver (it's not a Beyma) so it's kind of academic. 4" voice coil on it though - a real beast.

[Chienmortbb]

17 hours ago, Phil Starr said:

OK this is the frequency plot for 4 speakers. The Kappalite used by Barefaced (red) Beyma Sm212 (blue) Deltalite (purple) and the Faital 320 (green) all in the same cabinet 50litres. You know what the Deltalite's sound like so that gives you a starting point. They have a peak around 120Hz of about 2db which is colouring the bass and the bass rolls off slowly from there. The Beyma has a similar peak slightly les high than the Delta's but has the highest output at 40Hz of all the speakers. The FAital has the highest peak of all, around 3db and the highest output between 50-100Hz. the interesting one is the Kappalite with the most powerful magnet it has the flattest response down to 70Hz and then rolls off more quickly that the other speakers. Remember this is just the bass response up to 200Hz so not the whole picture.

 

Remember these are all in the same box, they can all be put in different boxes, the beyma would love a larger box and the Kappa would be better in a smaller box, or i can tune the boxes differently and shape the curves a little. Despite this I think it is fair to say the Beyma is going to have the deepest bass and the Kappa is going to be the most honest speaker with all the rest tending towards warm sounding.

Is that the kappalite Phil?

[Phil Starr]

The Red plot is the Kappalite John it gives a flatter plot in a smaller cabinet but I used the 50l cab as it was one they all worked in. Since we know @JPJlikes a warm old school sound I'll go back and look to see what's available that might be better than the Faital. Actually since you've been using the Faital how about telling us what you make of the bass response. Though I suspect @stevie will have tuned it lower in a 2-way cab.

[stevie]

On 23/07/2022 at 08:38, RichardH said:

 

No, it's actually a non-neo driver - I don't know the exact driver - though he did say it's a discontinued driver (it's not a Beyma) so it's kind of academic. 4" voice coil on it though - a real beast.

Despite the weight, it is actually a neo driver, Richard.