12" Cab Diary Continued

[Chienmortbb]

Phil that sounds so wrong.

[Gottastopbuyinggear]

Thought I'd give this thread a bump as it's gone a bit quiet in the last few months, and I'm getting the itch to do another cab build - not sure why as I don't need one, but hey...

I'm assuming from the number of responses in the thread that there wasn't enough interest in CNC'd flat pack kits to make that a possibility?

Any news on the new Faital driver that you mentioned, Stevie?  And any more feedback on the Mk II with Celestion horn driver Chienmortbb?

Also, I don't want to derail this thread, but do I recall one of you saying you were thinking of doing a 12/6 build?  I keep finding myself idly eyeing up the Fearful 12/6 plans, though I think I've talked myself out of that for a number of reasons, but I'd be interested in a similar idea with a more efficient (and lower cost) woofer, that didn't necessarily have to go quite as low.

Finally, and this may be a daft question but I'll throw it out there anyway - who knows, it might give you a laugh...  I'm currently gigging with two of the Mk I Basschat 1x12 cabs, and wondering whether one of the Mk IIs will be enough for me (where "enough" is obviously very subjective).  Is there any reason why I wouldn't get a similar sonic result from building a small box to house the HF driver and horn, and the crossover, and running that on top of one of the Mk I cabs, just to see whether it's "enough" for whatever subjective criteria my mind cooks up?

[stevie]

Yes, there have been developments, some of them you may find quite interesting. I'll explain in more detail when I've got a bit more spare time tomorrow.

[Phil Starr]

On ‎30‎/‎10‎/‎2017 at 21:56, Chienmortbb said:

Phil that sounds so wrong.
 

After so much time I had to check to see what I'd said

 

[Phil Starr]

20 hours ago, Gottastopbuyinggear said:

Thought I'd give this thread a bump as it's gone a bit quiet in the last few months, and I'm getting the itch to do another cab build - not sure why as I don't need one, but hey...

I'm assuming from the number of responses in the thread that there wasn't enough interest in CNC'd flat pack kits to make that a possibility?

Any news on the new Faital driver that you mentioned, Stevie?  And any more feedback on the Mk II with Celestion horn driver Chienmortbb?

Also, I don't want to derail this thread, but do I recall one of you saying you were thinking of doing a 12/6 build?  I keep finding myself idly eyeing up the Fearful 12/6 plans, though I think I've talked myself out of that for a number of reasons, but I'd be interested in a similar idea with a more efficient (and lower cost) woofer, that didn't necessarily have to go quite as low.

Finally, and this may be a daft question but I'll throw it out there anyway - who knows, it might give you a laugh...  I'm currently gigging with two of the Mk I Basschat 1x12 cabs, and wondering whether one of the Mk IIs will be enough for me (where "enough" is obviously very subjective).  Is there any reason why I wouldn't get a similar sonic result from building a small box to house the HF driver and horn, and the crossover, and running that on top of one of the Mk I cabs, just to see whether it's "enough" for whatever subjective criteria my mind cooks up?

Funnily enough I'd intended trying out my 6 in a separate box first, I see no reason why you shouldn't build the horn and crossover into a separate box other than that you would have to carry it on gig days. The crossover design published wouldn't be right for a pair of 12's though as they would present a 4ohm load.

Chienmortbb and I tried the mk 1 and 2 together at the last South West Bass Bash briefly, not an ideal environment as groups of bassists are as noisy as drummers but to me it sounded really promising.

[Gottastopbuyinggear]

 

16 hours ago, stevie said:

Yes, there have been developments, some of them you may find quite interesting. I'll explain in more detail when I've got a bit more spare time tomorrow.

Sounds good!

 

3 hours ago, Phil Starr said:

Funnily enough I'd intended trying out my 6 in a separate box first, I see no reason why you shouldn't build the horn and crossover into a separate box other than that you would have to carry it on gig days. The crossover design published wouldn't be right for a pair of 12's though as they would present a 4ohm load.

Chienmortbb and I tried the mk 1 and 2 together at the last South West Bass Bash briefly, not an ideal environment as groups of bassists are as noisy as drummers but to me it sounded really promising.

Yes, I was thinking I could try this on top of a single cab.  I wasn't thinking of this as a long term solution, and if I did it I'm sure the box would be functional rather than pretty...  On the other hand, I'm currently carrying 2 cabs, amp, pedal board, big bag of leads, mixer, and a powered monitor to every gig, and 2 bags of lights to some, so a small box isn't going to make much difference.  I even remember my bass most of the time!

Are you also thinking of building a 12/6 then, and if so would that be with the Beyma woofer?

You said I'd turn in to gottastopbuildinggear - well, it does seem to be turning into another form of GAS!  I did the Mk I cabs in 2016, a bitsa Precision last year, and it seems I'm casting around for something to make this year.

 

[Phil Starr]

Yes I'm continuing with the Beymas  as the basis for experimentation. I'm going down a different track to Stevie and John at the moment in my thinking, accepting that design is a compromise and looking for simple solutions that gig well even if they aren't perfect technically. In this case we've seen people arguing for years that anything above 6-8kHz isn't necessary for bass and that small cone drivers are more useful than horns. Now we are seeing the use of FRFR cabs for bass and the argument that control of dispersion of the middle and upper frequencies is a crucial component of a good sounding bass cab. I want to find out to what compromises are acceptable or even noticeable. There's a number of other issues I want to investigate too but I've got my own FRFR cabs and I want to compare them with using a 12+6 and a 12+3 (actually a 4x3 line source) The Beymas are a good platform for that as I they have good low frequency performance, are as flat as any other speakers in the midrange and don't have a lot of awkward personality issues meaning crossover design is simpler. They also have fairly typical sensitivity for a bass driver so if I do come up with a worthwhile DIY design it can be upgraded with a lot of other commercially available alternatives for the self builder.

[Chienmortbb]

3 hours ago, Phil Starr said:

bass

I think the truth is that Phil, Stevie and myself are all looking for the ideal cabinet and it does not exist. So it is a lifetimes work. 

One thing I will say about the MK2 with the huge single port is that if you like trouser flapping bass, in front of that port is this place to stand. I let a young bassist use mine the other day and he was effusive about it. 

It really does work.

As for using powered PA cabs as FRFR, I am not a fan. Those moulder plastic cases  do not pass Stevie’s finger test with the cab vibrating as some frequencies.

[stewblack]

Just finished reading this entire thread and it was fascinating. Definitely interested if the flat pack idea is revived. Will the cab be making an appearance at the SW bash?

[Phil Starr]

I'm pretty sure they will in one form or another. If |I can possibly get there I will. I haven't told anybody yet but I have toyed with the idea of building a cab whilst there, if anyone would be interested.

[stewblack]

21 minutes ago, Phil Starr said:

I'm pretty sure they will in one form or another. If |I can possibly get there I will. I haven't told anybody yet but I have toyed with the idea of building a cab whilst there, if anyone would be interested.

Oooooooh! For those vicarious carpenters and avid build diary readers out there, a live show would excite a near pornographic fervour. And encourage orders of more than a few flat packs too I shouldn't wonder.

[stevie]

On 24/01/2018 at 13:02, Gottastopbuyinggear said:

Thought I'd give this thread a bump as it's gone a bit quiet in the last few months, and I'm getting the itch to do another cab build - not sure why as I don't need one, but hey...

I'm assuming from the number of responses in the thread that there wasn't enough interest in CNC'd flat pack kits to make that a possibility?

Any news on the new Faital driver that you mentioned, Stevie?  And any more feedback on the Mk II with Celestion horn driver Chienmortbb?

Also, I don't want to derail this thread, but do I recall one of you saying you were thinking of doing a 12/6 build?  I keep finding myself idly eyeing up the Fearful 12/6 plans, though I think I've talked myself out of that for a number of reasons, but I'd be interested in a similar idea with a more efficient (and lower cost) woofer, that didn't necessarily have to go quite as low.

 

On the flat-pack idea, I think we got up to about half a dozen potential takers. I haven’t given up on the idea, but we haven’t reached critical mass yet. Maybe the next incarnation of this design will get some more interest.

I’ve designed and built a few bass cabs with midrange drivers, and gigged a cab with an 8” midrange chassis for a few years. I built my own take on the Fearful with an Eminence 3012LF and a Celestion sealed back midrange (the Celestion is much better than its price suggests but it needs some fancy crossover work). I also built a 15” system with the Beyma 6” neo midrange. Although I thought all of these were a worthwhile improvement on a single driver, I still much prefer a two-way system with a high-end  compression driver and this is the direction in which I am heading. Naturally, I’m still interested in finding out how Phil gets on with his line array design.

Both John (Chienmortbb) and I have been keen to try to get the weight of our cabs down a bit. He has been using the Beyma SM212 and Celestion CDX-1445 (as used in the Yamaha DXR series incidentally) in this cabinet with a fairly weighty crossover, while I have been using neos, albeit quite heavy ones. So we’re now on a mission to make a more lightweight 12” system, although it will of necessity be more expensive.

I received the Faital Pro chassis about a month ago – probably the first in the country – and this is what I have been working with in the odd hours I get to spend in my garage/workshop. For those interested in such things, it’s the 12PR320. It’s an uprated version of the 12PR300 used in the Vanderkley 112EXT and the Bergantino CN212 which beat all-comers at the Essex Bass Bash cab shootout a few years ago.

The main improvement over the PR300 is in its xmax, which has now gone up to 7.37mm. Its 300W power handling matches the 8-ohm output capability of the popular lightweight amps, it weighs in at a fantastic 2.5kg and is very well priced (by Blue Aran) at about £130. It works well in our Basschat cabinet, although it looks like it will have even more low-end oomph in a slightly larger cabinet. We’ll see.

I’m not messing around with cheap tweeters this time round. I’m using a top-of-the range Celestion 1” neo (the one above the model used in the QSC K-series and the one used by Duke Lejeune in  his multi-thousand dollar hi-fi cabs) on an asymmetrical CD horn and crossing over at 1.5kHz. I’ve already designed the crossover, although I still have to tweak it. It’s complex and won’t be cheap, but this is a no-compromise box – so it has to be right. This will be a genuine FRFR design. You’ll be able to use it for keyboards, for PA, or as a monitor. I expect it to sound at least as good as the Yamaha PA cabs that are getting such a good press at the moment – but it will be designed specifically with the unique requirements of bass guitar sound reinforcement in mind.

The drivers I’m using have distribution in the US - so we might even get some input from our US contributors, where DIY cabs seem to be a lot more popular than here. I’m not sure how they’ll deal with our new-fangled millimetres though…..

Chienmortbb and I don’t live too far away from each other and we’ll be getting together in a few weeks’ time to check the new design out and compare it to the previous incarnation. We’re hoping Phil can make it as well. Anyone else within travelling distance of Dorchester is welcome to join us if they can bring a high-end 12” bass cab along with them for comparison purposes.

And yes, the new cab will be at the SW Bass Bash. I have to be there to watch Phil building a cab in a day.

 

Edited January 27, 2018 by stevie

[scrumpymike]

3 hours ago, stewblack said:

Oooooooh! For those vicarious carpenters and avid build diary readers out there, a live show would excite a near pornographic fervour. And encourage orders of more than a few flat packs too I shouldn't wonder.

I'd not seen this until stewblack flagged it up to me with a pm (thanks for that).  All I can say is bring it on Phil!

[Phil Starr]

Looks like I'm committed then. I'm wondering how quickly I can do it. Maybe we should have a sweepstake

 

[Gottastopbuyinggear]

Stevie, is your no-compromise design going to be using the Mk 2 cab as currently designed or will you be making adjustments (more than bracing arrangement) to it?  Reason for asking is that I may have an excuse to get over to Bristol in the week at some point in February, so I'm thinking about placing an order with Avon Ply - I used them last time and they did a great job of cutting the panels to size.  Unfortunately they're not open at weekends, and I live in Cardiff and work in Swansea so I'm a bit scuppered most of the time.  So far I've not found anyone local that can source the Poplar ply and cut it to size.

[stevie]

I'm using the same cab for the no-expense-spared version. The baffle cutouts will be very slightly different because of the different horn. Unfortunately, the cab drawings on page one of this thread disappeared when Basschat relocated, but if you have them, Gotta, just give the cutting list to Avon. Chienmort and I have already assembled cabs cut from that list by a wood merchant and they go together perfectly. You'll get two cabs out of an 8 x 4' sheet. Maybe someone else in South Wales would like one.

I'll try to replace the drawings some time. A lot of the assembly photos have gone too. I've replaced a few and will do the remainder as time allows. Also, some of the additional bracing tweaks I did (in addition to those shown in the drawings) proved to be unnecessary. I'll revisit and revise those posts later.

One final thing - I found that I needed a lot of clamps to assemble the box because if you're going to paint it you have to line the joints up very accurately. So assembly took some time because I had to wait for each section of the box to dry before I could to re-use the clamps elsewhere. However, I have read on some other specialist speaker sites that some builders are using Spax screws very successfully. These are German screws that need no predrilling but go straight into the wood without splitting it. Naturally, you need to remove them and fill the holes later, but a box of Spax screws should save a lot of time and cost a lot less than eight long clamps. I'm sure some of the woodworkers will comment.

 

Edited January 30, 2018 by stevie

[stevie]

I finally managed to replace all the photos. As you can see, there are now just two circular braces with some supporting battens. I'll get the drawings up as soon as I figure out how to do it.

[RichardH]

Stevie, I have copies of the PDFs if you don't? Though I assume it's more a matter of how to upload them to the thread rather than access to the PDFs....

[stevie]

My problem is locating the latest versions on my computer, Richard, because we went through a number of changes. I'm sure I can find them, but if you could PM me the PDFs, I'll re-attach them to the first post in the thread.

[stevie]

Thanks Richard. The drawings are now pinned to Post #1. The cut list is accurate. However, the cab assembly drawing is of the prototype; it shows a couple of braces that are not needed (I and J) and does not show the braces on the back panel, or the vertical brace on the front baffle between the horn and port apertures. We'll get that fixed as soon as we can. Nevertheless, if you have your wood cut based on the cut list and refer to the photos when assembling, all should be clear.

Edited January 31, 2018 by stevie

[stewblack]

22 hours ago, Gottastopbuyinggear said:

Stevie, is your no-compromise design going to be using the Mk 2 cab as currently designed or will you be making adjustments (more than bracing arrangement) to it?  Reason for asking is that I may have an excuse to get over to Bristol in the week at some point in February, so I'm thinking about placing an order with Avon Ply - I used them last time and they did a great job of cutting the panels to size.  Unfortunately they're not open at weekends, and I live in Cardiff and work in Swansea so I'm a bit scuppered most of the time.  So far I've not found anyone local that can source the Poplar ply and cut it to size.

+1 for Avon Ply. Good people to deal with and good workmanship.

[Chienmortbb]

Stevie and I got ours cut at Timbmet. They offer an on-site cutting service (although not while you wait) but they are accurate unlike BnQ. They will also do a full CNC service for quantity. 

I looking at redrawing to make assembly easier if (as Stevie says) their is enough interest.

[Passinwind]

On 1/27/2018 at 10:11, stevie said:

I'm not messing around with cheap tweeters this time round. I’m using a top-of-the range Celestion 1” neo (the one above the model used in the QSC K-series and the one used by Duke Lejeune in  his multi-thousand dollar hi-fi cabs) on an asymmetrical CD horn and crossing over at 1.5kHz. I’ve already designed the crossover, although I still have to tweak it. It’s complex and won’t be cheap, but this is a no-compromise box – so it has to be right. This will be a genuine FRFR design. You’ll be able to use it for keyboards, for PA, or as a monitor. I expect it to sound at least as good as the Yamaha PA cabs that are getting such a good press at the moment – but it will be designed specifically with the unique requirements of bass guitar sound reinforcement in mind.
 

Nice. Duke provided a new prototype TC112 NAMM cab for the Marco Bass Guitar booth I was in this year. It used the same Celestion  compression driver he uses in his TC115 and TC118 cabs. The TC118 has always been among my very favorite bass cabs, and that compression driver plays a big part in that. There was also a secondary top-firing tweeter, meant to spill around the amp sitting over it. Seemed very far fetched, but it actually worked quite well. Very much looking forward to seeing you new iteration come to fruition!

Edited February 5, 2018 by Passinwind
spelling errors

[RichardH]

Looking at the spec of the PR300 and PR320, the PR300 appears to be a touch more efficient (at 99dB rather than 97dB). I am assuming that the extra XMAX of the PR320 more than compensates for this difference - and I suspect that the measurement of efficiency is not such a clear cut thing as a single number suggests...

 

[stevie]

On 05/02/2018 at 04:21, Passinwind said:

Nice. Duke provided a new prototype TC112 NAMM cab for the Marco Bass Guitar booth I was in this year. It used the same Celestion  compression driver he uses in his TC115 and TC118 cabs. The TC118 has always been among my very favorite bass cabs, and that compression driver plays a big part in that. There was also a secondary top-firing tweeter, meant to spill around the amp sitting over it. Seemed very far fetched, but it actually worked quite well. Very much looking forward to seeing you new iteration come to fruition!

Thanks, Charlie.  I find that using a good compression driver (with the right horn) in a bass cab makes a huge difference. Unfortunately, good ones cost nearly as much as the bass drivers themselves. On the rare occasion that I pop over to the dark side, I am always impressed by what Duke is getting up to. He's virtually the only person in the business who continues to push the envelope and provide practical solutions to the problems bassists have with their cabs.

The particular problems that this new design tries to address are:

1. Hearing yourself clearly in front of your compact cab without having to raise it, tilt it or stick another cab on top of it.

2. Hearing the same sound you are sending to the audience (how else can you balance your sound properly?).

3. Producing a sound that does not change when you move around the cab.

4. Producing a sound that is balanced without needing a second cabinet to boost the bottom end.

5. Producing a sound that "throws" into the audience and retains clarity (i.e. doesn't become boomy) at a distance.

5. Having a flat frequency response cabinet that doesn't need endless fiddling  with your amp's midrange controls before it sounds right.

I can see that these are the kinds of things that Duke is also takes into consideration in his designs - so I feel that I'm, in good company.

 

 

Edited February 6, 2018 by stevie