Help with 1x15 build

[AEA]

hey guys,

I have been interested in building a lightweight 1x15 reflex cab similar to a half sunn 200s cab modified to use bracing and 1/2" ply. Now these cabs have a port that becomes angled 45 degrees about halfway in.

How does this affect the tuning of the cab?

What program can I use for optimising the design for use with either a 3015 or 15pr400? Will any include this style of design?



Any other advice for designing this style of cab is more than welcome!
 

[Walt-Dogg]

hey guys,

I have been interested in building a lightweight 1x15 reflex cab similar to a half sunn 200s cab modified to use bracing and 1/2" ply. Now these cabs have a port that becomes angled 45 degrees about halfway in.

How does this affect the tuning of the cab?

What program can I use for optimising the design for use with either a 3015 or 15pr400? Will any include this style of design?



Any other advice for designing this style of cab is more than welcome!

Sounds similar to the 1x15(X) or 1x18(X) so me.I've always wanted a pair of JBL loaded 15s or Vega loaded 18s.

You'll want to design the box around speaker in something like WinISD, you can set up the encloser like the sunn but use the software to tune the angle and depth of the vent/port and overall dimension of the cab.

[EdBass]

It's just a folded configuration of a ducted port. I believe Conrad Sundholm said the design came to him in a dream, and referred to the design as a a "folded horn port". Works for me, can't argue with the man who designed it, and there is NO question the design works fantastically in a bass guitar application.

That cab was designed in an era that predates the modern freeware that makes anyone with a PC an "acoustical engineer".
WinISD is released as freeware and suddenly every enthusiast forum on the planet is filled with self proclaimed "internet experts" on MI cab design, blathering on about what can't sound good, and how MI amp rigs should be designed.
Here's an example; spec (and WinISD) wise the SVT 810 is horrible as a full range cab, high mid heavy with bass response that falls off a table at around 100hz. For some reason bass players who can have anything they want still use them on big league pro stages all over the world.
I guess these pro players and sound engineers don't know that they are so terrible, and that a passively crossed over bass cab with a compression driver is a much better choice. I guess they don't pay much attention to internet forum speaker gurus...
 
I think you would find it difficult or even impossible to accurately emulate the response characteristics of the 200S cab in freeware like WinISD, you would need something more sophisticated (as in expensive), and have the training to use it.

Not that all of this really matters, for a couple of reasons;

MI cabs are different than SR cabs, their design spec isn't to as efficiently and accurately reproduce the designated range of the driver they are designed to enclose. They are designed to sound good amplifying the instrument they are meant to be used for, which is usually a much less exacting task. MI cabs primarily are sound/tone producers rather than the program sound reproducers that SR cabs are.

But more importantly, if you are looking for the best enclosure for a specific Eminence or Faital driver, ask Eminence or Faital rather than try to adapt or modify a design that was meant for a JBL D140F in the mid 60's. Seriously, the driver manufacturers know what parameters work for ANY specific application for the drivers they produce, and it's not a secret; they will tell you what these parameters are and point you in the right direction.

Sorry about the little rant, but try contacting the manufacturer(s) of the drivers in question. No one will have more insight/experience/expertise into making their drivers work well than they do!

[Soundmasterg]

You may find some inspiration from post # 29 and #42 in this thread >> http://sunnforum.ampage.org/index.php/topic,10005.28.html where I show the 1x15 cabinet I made. When upright it has the same width as a 200S head and when on its side it is the same width as a 2000S head. It is also as deep as a 2000S cabinet front to back. The port is at the bottom and is half as tall as the full size 2x15 200S cabinet to keep the frequency response the same. I used a JBL E140 in the cabinet and later added some 6 inch tweeters, and it is internally braced. The back lower area of the cabinet is made like a modern Ampeg SVT cabinet with the angle and casters mounted there. The cabinet is using 3/4" plywood, which I suggest as even with bracing the 1/2" will likely flap around more than you would like. I also highly suggest to put stuff in the cabinet to dampen the reflections like foam or similar. I also highly suggest to front mount the speaker. If you want take a look at the pics I posted on the thread above.

I agree with Ed about going to the manufacturer's page to get the specs and you can try to use those programs to design a cabinet that will work for a given speaker, but keep in mind those programs usually assume a round port and not a full width Sunn style port. The cabinet that I made sounds fantastic and very similar to a 200S cabinet with slightly different bass response due to the different speaker.

Greg

[AEA]

Thanks. This is all contrary to the advice I have gotten from other forums.
I have had most people tell me to go and use a fearful design. Either that or I was told the angled port will have no affect on the response of the cab and to use something from wines.

Really liking the 200s and 2000s I really would rather had down that route so I'm glad to have been given some great advice and positive feedback.

I have heard a 2000s with the 15pr400 and it sounded great. They have the d140 vibe and so that's why I was interested in using them. My main concern with halving the port size was whether there would be some interaction between 2 speakers using the port together. So it's as simple as halving the port?

My plan is to build one cab then if it is what I'm hoping for building a second for a stack.

Greg how much bracing did you use in your cab? How heavy did yours turn out?

Cheers again guys!

[EdBass]

Sounds like you have been on talkbass. These "fearful" cabinets are actually an amateurishly simple reflex cab design with a passively crossed over tweeter, probably better suited for a small venue high pack in a weekend warrior SR system. Not dissimilar to the homebuilt Hi-Fi speaker designs of the late 1950's - early 1960's. Designed (probably on WinISD freeware) several years ago by a "wanna be" faux audio engineer who offered the plans for free online.
Through self promotion this fella gained some traction as an "internet expert" about transducer science on talkbass, mostly among the neophyte bass player members that really had no other frame of reference in the real world of audio engineering, and a cult like devotion to his "fearful" designs grew over a few years. As a fan of low/no cost marketing myself, this in and of itself is just dandy as far as I'm concerned.
It irks me (obviously), not because someone bulk posted on a free forum promoting his beginner level, freeware design as the greatest bass cab ever conceived; as I said that's just good marketing in my book, but because this wanna be and his follow the leader cult also vehemently bashed any thread about bass cabs that were NOT his bush league design. That type of behavior is classless and rude even from folks who actually know what they are talking about, and extremely disruptive and counter productive from posters who don't have a clue what they are posting about, and just parrot what they have seen other post on the subject in an attempt to readers that they do know about the subject.

As I said earlier, in the MI world it's about sounding good rather than what the actual response characteristics of a cab are; as opposed to in the Sound Reinforcement world where technology constantly improves the state of the art. Classic MI cabs were largely designed "by ear", because obviously the technology that pretty much everyone now has at their fingertips wasn't available then. For that matter, many iconic, most popular and still used MI cabs were designed before Mr. Small even began expanding on Mr. Thiele's research and adapting it to early computer models.
Many of the modern cabs that are highly regarded and commonly used in the professional world of live and studio Musical Instrument amplification still rely on ears for the final testing, although modern design software saves a BUNCH of trees compared to the old "build it and try it" R&D methods.

All that said, it's in the ear of the end user where the decision should be made, there is no "best". "Best" in what sounds good is like saying what the "best" color is or what the "best" flavor is, can't be done. As I said, what irks me about the "fearful" thing isn't the cabinet itself, I'm not a fan of passive crossovers or tweeters in a bass guitar cabinet from a technical standpoint, but I don't doubt that many players are satisfied with the performance of the cabs. It's the attitude among its supporters that fearfuls are the end all/be all BEST bass cab out there, and using or preferring anything else makes a person ignorant and/or unenlightened and needing to be "corrected" in an open forum.
In fact, if a bass player feels the need to go the full range accurate route with a bass rig, the most efficient route would be to invest in a commercially produced powered full range SR cab. Even the inexpensive weekend warrior class equipment absolutely destroys any fearful design from a sound quality, power to weight, or cost efficient angle. Latest and greatest design technology, uber light, nearly indestructible polymer materials, on-board megawatt and accurate class D amps, neodymium drivers; the "big league" version on what the "fearful" design is the homemade "beginner designer" version of, and can be bought for dirt cheap.

Back the the Sunn cabs, they are very flexible as far as drivers. The only exception to that would be the 200S's restrictive port ducting that can make some larger ceramic magnet or deep frame drivers difficult to fit in a traditional rear loading configuration. Tonally I probably like the tone and response of the AlNiCo JBL's in Sunn cabs, but from a practical angle several more current drivers fit the bill quite well.

[Walt-Dogg]

Wow, Ed you really hit the nail on the head. Those guys on TB just love to ram myth down your throat and it gets tiring.

I suggest WinISD with a grain of salt, use it just to get an idea of the speaker response if you can't get the specs from the manufacturer.

Because, in the long run, if it sounds good. Just run with it.

[loudthud]

There is an interesting cabinet design that came from an engineer at JBL, George Augspurger in 1961. Most of what you need to know about it can be found here: http://www.diyaudio.com/forums/multi-way/3699-article-about-double-chamber-speaker-enclosure.html

I first learned about it when I read the 1980 Speaker Builder article. I built one by installing a partition in an old Bassman 2X12 cabinet and used a D140. The internal volume of the cabinet was close to the 3 cubic feet of the original. It worked suprisingly well. The tuning is not critical so it should work well with any bass speaker.

[Soundmasterg]

Thanks. This is all contrary to the advice I have gotten from other forums.
I have had most people tell me to go and use a fearful design. Either that or I was told the angled port will have no affect on the response of the cab and to use something from wines.

Really liking the 200s and 2000s I really would rather had down that route so I'm glad to have been given some great advice and positive feedback.

I have heard a 2000s with the 15pr400 and it sounded great. They have the d140 vibe and so that's why I was interested in using them. My main concern with halving the port size was whether there would be some interaction between 2 speakers using the port together. So it's as simple as halving the port?

My plan is to build one cab then if it is what I'm hoping for building a second for a stack.

Greg how much bracing did you use in your cab? How heavy did yours turn out?

Cheers again guys!

Halving the speaker port is done to get the same frequency response out of the 1x15 cabinet as you would get from a full size 2x15 cabinet. It will mostly get you there, however the bigger cabinet does get slightly lower frequency capability compared to the smaller cabinet, just because of the size difference, but if I remember the LMS plots it was less than 2 dB difference at 40 Hz. Since I used a JBL E140 in my 1x15 cabinet, and the 200S cabinet we measured on the LMS system used JBL D140's, there is already that difference there anyway that probably swamps whatever frequency difference the cabinet makes. Overall the plots between my 1x15 and the Sunn 200S 2x15 cabinet were very close to each other, and that was before I added the 6 inch tweeters, which obviously bumped up the high end. Conrad designed the crossovers for me, but I am not entirely happy with those speakers and will add a switch to disconnect or connect them at some point. I haven't taken plots of my 2000S cabinet yet, though I would expect a better bottom end due to the bigger cabinet. Conrad and I will probably play around with that next spring or summer, but we'll see.

Initially I didn't have bracing in my cabinet and if I played a distorted 200S head through the cabinet, with the head on the top of the cabinet, the cabinet would scoot itself across the room backwards until it pulled the cord out of the bass....haha. So I braced it inside a lot, and that issue was sorted. Of course the cabinet is heavier now, but part of the weight is the speaker as the E140 is a heavy one. That weight is why I put it on wheels and put the handles on the back and sides so it can be easily moved and transported. As for an exact weight, I don't know....I never bothered to weigh it. Its certainly lighter than a 2x15 or an SVT cabinet though! The bracing goes around all edges, and there is some connecting the baffle board to the back too, but I would have to open it up to see what I did again. Its been since like 2008 when I made it.

Greg

[AEA]

So it's looking like I'm going to build half of a 215s. I think I will build one to spec and then use that as a reference for a lighter version. Just trying to get in touch with Conrad to get the plans. The email from his website came back as undeliverable. Anyone have any luck getting in touch with him?

I'm still doing my research on different ways to brace and lighten a cab without affecting the overall tone too much. There is so much conflicting opinion and "evidence" that makes me think I'll be doing a bit more experimenting with the 2nd cab. Any suggestions or thoughts?

I am going to do a build thread and hopefully try a few different speakers. I'm really looking forward to getting started. This forum has been really inspiring. Hopefully some of you will enjoy my project!

[EdBass]

Not sure about Conrad's email address issues, but I doubt he would have much info about the 215S. I'm 99% sure that was a Hartzell design; produced after he sold Sunn.

[AEA]

Oh ok thanks Ed. So how would I go about finding a 215s design? Might just start with the 200s as it seems to be the more documented in here anyway

[Soundmasterg]

So it's looking like I'm going to build half of a 215s. I think I will build one to spec and then use that as a reference for a lighter version. Just trying to get in touch with Conrad to get the plans. The email from his website came back as undeliverable. Anyone have any luck getting in touch with him?

I'm still doing my research on different ways to brace and lighten a cab without affecting the overall tone too much. There is so much conflicting opinion and "evidence" that makes me think I'll be doing a bit more experimenting with the 2nd cab. Any suggestions or thoughts?

I am going to do a build thread and hopefully try a few different speakers. I'm really looking forward to getting started. This forum has been really inspiring. Hopefully some of you will enjoy my project!

Conrad changed his email address and hasn't updated his website yet. Let me reach out to him before sharing his new address and I will get back to you.

Greg

[boulderbass]

Sounds like you have been on talkbass. These "fearful" cabinets are actually an amateurishly simple reflex cab design with a passively crossed over tweeter, probably better suited for a small venue high pack in a weekend warrior SR system. Not dissimilar to the homebuilt Hi-Fi speaker designs of the late 1950's - early 1960's. Designed (probably on WinISD freeware) several years ago by a "wanna be" faux audio engineer who offered the plans for free online.

Have you ever played a fEARful? They are a great bass guitar cabinet. While most of my bass playing is done through a small 1x15" with a K140, because I love that JBL midrange, the fEARful is always what I play through when playing with a new band or if the opener is going to use my rig. Pretty much every guy who has played through my rig with it has been blown away, not to mention all the non bass players who hear it. After all, most bass is heard in the room directly from the DI so why not have a bass cabinet on stage that does what a PA does? After all, no one in the room is going to hear your carefully sculpted tone in the room unless the cab is mic'ed. Or maybe the venues you play don't run the bass through the PA.

Sunn cabs with JBLs sound great, I love mine, but that's no reason to hate on the fEARful. They are excellent cabs for a good price and have an excellent performance to weight ratio.