Budget 40-10k+hz 100db/w planning

Short summary 2019.03.01
I do not have any intentions of bragging, this project was just for fun, and on the cheap. I think the best part of this hobby is trying to get more for less.
Most of the useful material is on page 10 in this thread.

Nothing magical or special about it, the ultimate goal was, as you can see, to go from 40hz to 10khz in around 300 liters per channel +/- some %, as cheaply as possible.
Part reason was because after a lot of trial and error, I became a fan of no-boost eq when eq was required. It is much easier and cheaper to cut the tops than fill the valleys, and it sounds better too. So to get proper 95dbw I had to set the goal of 100dbw, but eventually had to concede and change it to 100db/2,83v, or the speakers would have been much bigger than 300 liters per channel.

After a lot of pondering and checking out various drivers, suddenly Fane decided the world was ready for FC152!
I did not want to hope too much, but it was cheap, so I took a chance. Now this driver is called 15-300TC. I eventually settled on the Fane 15-400 for bass, they are discontinued now. If there's any interest at all in my box design, the Fane 15-600 Pro (do not use the LF version!) is a better driver in most aspects except price. Many other drivers can be used, it is a reasonably flexible design.
I do not recommend OSB as cabinet material, it is sturdy enough, and cheap, but it can be very hard to make a pretty end result, takes a lot of work.

Update 2017.11.18
The speakers are alive and playing! Finish will have to wait until spring. But they sound absolutely fantastic!

Budget 40-10k+hz 100db/w planning



Update 2017.10.30:
After a long time of looking around and checking specs, manufacturers and drivers I stumbled over the Fane FC152 in the Fullrange forum, and nearly immediately decided to go for a solution with this new 15" full range driver and the Fane Sovereign 15-400.
Post on actual progress: Budget 40-10k+hz 100db/w planning


Original 1st post:
Hey guys.

Had a some various bottles of really great (strong) beer + ca 3/4 bottle of good wine and a couple of glasses of good Akkevit (Aqua Vitae, water of life 40% alcohol, originally intented as medicine tracing back to the 1500's or so, my mind'll be sharper in another 12 hours, but great for a cold or flu though), just to excuse myself from the occassional typo.

Background:
Anyway. I've been contemplating this for several months now, and allthough I'm just getting the adjustments on the 4way setup together after moving house (Hawthorne ssi 10" and beta15a + my very very nice Beyma 12BR70 T-TQWT's). I can not stop myself thinking that going the PA way would somehow help my, ehm... itch for better dynamics in a confined environment (aim for sensitivity and screw the really low end because it takes too much space).

The long(ish) term project plan (finish construction during 2016 if everything seems OK):
1. Figuring optimal design and size for the bass "solution", maximum size around 200 liters each, must go absolutely flat to 40hz or prefferably 38hz before roll off at ca 100db/w, need two of those. want minimal delay reproduction, and would prefer to stay out of TH and BR country based on personal bias. Unless really good data can make me reconsider. What are my options?

2. Really want to give those Karlson enclosures a go for the tops, AND they can be placed in the ceiling? Pluses are off axis dispersion and tight control of cone movement. Open for suggestions, also the diysoundgroup 88 special is very interesting, but do not like the placement of BR ports at all LINK Makes it just a little bit wider than my goals for the tops.

Allright, what is the catch? summary of design goals?
1. As cheap as possible! I used to spend about 5000$/year on stereo until DIY found me, now it's an eternal hunt for squeezing as much really high end listening experience as possible out of as little $ as possible, the fun is in the hunt.

2.Prefferably ruler flat 100db/w from 40hz-10khz, it's fun to have things that rattle the environment to about 23hz, but sensitivity could be much increased with 40hz being the limit, and some studios mess up the sub 40hz content, not many get it right. Some factory work in the recent years brought my hearing down to 16500hz, but my experience is that as long as you aim for good performance up to 10k it's mostly accepted and not much is missed.

3. Size: max 200 liters per bass bin pending on format, and would prefer to keep max width of tops at 40-45cm (wall or ceiling mountable). I'd be happy if the boxes would be kept at 1 sheet each, or possibly planned with 15mm OSB with extra bracing for lower cost.

Anyone have any good suggestions? some 1/4 wave horn bins with 15" perhaps for the bass? But what about the tops? Karlson of some kind, the 88 special or some other alternative?

I am very serious about this, my goal is going up in fidelity and sensitivity, but down in cost, and the major motivation is the fun of it all.
 
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Allright. So after some time searching about it seems difficult to get away from the good 'ol Beyma 12br70 on a strict budget. 2 per channel in ~120l box/each with also separate power amps will not be 100dbw, but not too far off. Also seems hard to escape from the faital 3fe25 when considering cost, in a quad per channel the 16ohm version seems the easy choice, but with an abundance of power amps laying about and considering the variations in frequency response between the different versions, the 8ohm version may be the better choice set up as 2*4ohm load per channel, and if assuming a 88db sensitivity instead of the 91db given in the text part of the spec sheet, it will still achieve a total of 100db with 1 power stage per 2 drivers *2 per channel running 2.83v. Granted, this feels like cheating, but 8 faital 3fe25 and 4 beyma 12br70 seems to me the cheapest way to reach the original goal and retaining some degree of quality.

Open for alternative suggestions. :)
 
Why don't you use some cheap PA chassis? For the bass i.e. the Kenford 15" chassis (-> eBay), from ~1000-1500Hz either also a Kenford driver with 2" diaphragm (Comp 50, little DIY mod improves it a lot) or a BMS 4554. Alternatively 3 way with a cone pa mid chassis and a waveguide.

Yes. But a lot of the cheap pa stuff rolls off at maybe 50-55hz, goal is flat to 40. Also 1 good 15" may be around 95dbw. The beyma 12br70 with the right box can be around 93dbw in halfspace, two per channel with their own power stages (3db +3db) gets me close to 99db. I'll have to make some compromise somewhere. Could use 15mm osb for material, just have to brace it right.

Also it is my assumption that the faital 3fe25 will sound better/$ than some 3way cheap pa speaker with unoptimized xo. Though I may be wrong.

Edit: where could I find the specs of those kenford drivers?

Edit2 nvm found it here, would be nice to see some measurements though
http://www.technikservice-trautmann.de/index.php?cat=KAT08&product=P000269
 
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Yes. But a lot of the cheap pa stuff rolls off at maybe 50-55hz, goal is flat to 40.

There are a lot of PA drivers which go easily flat to 40Hz.

Also 1 good 15" may be around 95dbw. The beyma 12br70 with the right box can be around 93dbw in halfspace, two per channel with their own power stages (3db +3db) gets me close to 99db.

The Beyma are fine but let's be honest, you can't compare catalogue specs. Look at the datasheet of the 12br70, the 93dB are only reached between 120 and 150 and over 700Hz, the other ranges are more around 90dB. On the other hand, if you're really calculating with that as 93dB, then you have to use the 98-99dB specs of the PA chassis aswell.

Also it is my assumption that the faital 3fe25 will sound better/$ than some 3way cheap pa speaker with unoptimized xo. Though I may be wrong.

Well, you want 100dB, the 3FE25 got honest 88dB (91dB only in the high range, again, look at the data sheet). For 100dB you need ~17W and the driver is rated 20W rms. That means, with that much power the distortion rises a LOT and you don't have much (if any) dynamic left. That is, if you go active and use one chassis. If you go passive, you can't reach the 100dB, you'd need ~8 of the 3FE25 for 97dB and that's not really cheap either. A horn isn't a solution in this situation because you can realistically gain max. 6dB, which isn't enough and the gain won't be over the whole range.

For the xo: You have to optimize it anyway or more: develop it completely from scratch, no matter what drivers you use. Any existing or 'universal' xo will just save the drivers from a quick, sudden death but nothing more, if you want to sound it good, salvage and scrap these.

Edit2 nvm found it here, would be nice to see some measurements though
- Lautsprecher - 15 Zoll Kenford PA 15" Subwoofer 300W RMS

Well, you don't have to use the Kenford, they are the cheapest I'd go with. But there are a lot of other very good chassis available for low cost. Maybe it would be easier to find suitable chassis if you't say something about your budget.
 
Icg:
I have no desire to argue with you. Yes, there are many pa drivers that fulfill my criteria. I do not know them all, but many of the ones with desireable specs are either 1: expensive or 2: poor quality.

I am already in the posession of some 12br70 in a couple of t-tqwt, and have a fair knowledge of their limitations and weaknesses, they are however very good build quality, have realistic specs, and can be bought without the need of shipping.

Regarding the 3fe25, you must have misread my post, because 4 (a quad) per channel will not give me 100db/w but I will settle for 100db/2.83v. As I see it, the reason a 3way will not work is because I have trouble finding a good enough midrange. I already have some radian 475pb that can be used. If you know for a fact some pa midrange that will get me to 100db/2.83v I will seriously consider it. As far as I can estimate it would be nice to stay below 8" if using double drivers for midrange to avoid certain issues.

That kenford driver may be quite good. But it would be nice to see more data on it. It is stated as a 97db/w driver. But the 12br70 is also listed as a 95db/w driver and the absolute most I will expect from it in a very optimized design is 93db/

Edit.
I do not have a budget restriction. The goal is as cheap as possible with as good sound and dynamics as possible. There are no budget restrictions, but the goal is low total cost of complete system.
 
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If you know for a fact some pa midrange that will get me to 100db/2.83v I will seriously consider it. As far as I can estimate it would be nice to stay below 8" if using double drivers for midrange to avoid certain issues.

Well, 4x 80mm chassis are still 32cm (or 12,6 inch), which gives you significant vertical beaming. Depending on how far they should go up, you'll have interference problems and need quite a listening distance for homogene sound reproduction.

For the 100dB/2,83V: That works, but only if it's okay for your amp to go as low as 2 Ohm. Every doubled membrane surface and every halved impedance (because of the double power) gives you +3dB each. 88dB +3dB for doubling the membrane surface gives you 91dB, +3 dB for twice the power equals 94dB/2,83V at (roughly) 4 Ohm for two chassis. The next +3 dB for doubling the surface (now 4 drivers) and again +3dB for halving the impedance again, which results in 2 Ohm. I don't know if your amp likes that, I'd honestly really try to avoid such low impedances but if you want to go for it, it's your setup ofcourse.

That kenford driver may be quite good. But it would be nice to see more data on it. It is stated as a 97db/w driver. But the 12br70 is also listed as a 95db/w driver and the absolute most I will expect from it in a very optimized design is 93db/

The Kenford is excellent bang for the buck, regarding lowcost it's a great choice but it's not the best driver in the world.

You are mistaken with the 95dB of the 12BR70. The
datasheet (PDF) says 93dB (not 95), the measurement diagram shows more honest 90-91dB with some higher peaks.

I do not have a budget restriction. The goal is as cheap as possible with as good sound and dynamics as possible. There are no budget restrictions, but the goal is low total cost of complete system.

Okay, with that in mind you could go for something else than the Kenford. You could have a look at the Mivoc AWX184 i.e.
 
Icg:
Again. Somewhere inside my vast amount of text I mentioned using either the 16ohm version of 3fe25 or more prefferably 1 power stage per 2*8ohm 3fe25 so 1 power amp per 4ohm load. I have lots of small power amps laying about. I can have 1 per driver if i want, but thats a bit excessive.

The 3fe25 do not have to be in a perfect line either. I also mentioned the possibillity of using a karlson type enclosure. Nothing is decided, I will choose the most effective option using the criteria allready specified.
 
Again. Somewhere inside my vast amount of text I mentioned using either the 16ohm version of 3fe25 or more prefferably 1 power stage per 2*8ohm 3fe25 so 1 power amp per 4ohm load. I have lots of small power amps laying about. I can have 1 per driver if i want, but thats a bit excessive.

You wrote 100dB/W and that's in the thread headline. Then you somewhere in your vast ammount of text wrote 100dB/2.83V. With 4, 8, 16 Ohm or multiple amps you get neither. If you want to go full active, well, then do it, but then the spl doesn't matter.

The 3fe25 do not have to be in a perfect line either.

You don't have to. But that would mean to introduce horizontal interferences - which is much worse than vertical.

I also mentioned the possibillity of using a karlson type enclosure. Nothing is decided, I will choose the most effective option using the criteria allready specified.

A Karlsson coupler is interesting. The limit is still the lower end, which in the Karlsson coupler is equal to BR because, well, it actually is a special form of a BR enclosure.
 
Icg:
You are correct in that 100dbw was the original goal. But after much serious thought and investigating various options I decided that 100db/2.83v is a more realistic goal. Given that the bass bins are limited to 200 to absolute max 250 liters per channel.

Spl does matter, but size constraints trump spl, fidelity (freq extension) also trumps spl. So priority is 1. Max size 200l +/- 20% for bass per channel 2. Frequency extension/peaks dips/flat response 3. spl/w

You must understand that I very much value criticism as a means to improve ideas and optimize the end result.
If you have any alternative ideas, design suggestions or drivers that can be used I would be grateful for anything constructive you have to offer. I will continue to pursue information about the drivers you suggested.

But so far the majority of your replies have been nitpicking, and I do not like it.

This is a difficult challenge, I want as good an end result as possible at the lowest cost possible. Arguing is just wasting time.
 
A Karlsson coupler is interesting. The limit is still the lower end, which in the Karlsson coupler is equal to BR because, well, it actually is a special form of a BR enclosure.
A Karlson cabinet is not the equal to a standard BR because much of the Helmholtz resonator volume is taken up by the front chamber, reducing low frequency output compared to net volume.

Kaffiman has requested flat frequency response, not what a Karlson is known for, the "slam" and so forth used to describe them are due to the elevated upper mid bass associated with the front chamber band pass.
 
A Karlson cabinet is not the equal to a standard BR because much of the Helmholtz resonator volume is taken up by the front chamber, reducing low frequency output compared to net volume.

Kaffiman has requested flat frequency response, not what a Karlson is known for, the "slam" and so forth used to describe them are due to the elevated upper mid bass associated with the front chamber band pass.

Not sure if I have understood things correctly, but from the threads about karlson enclosures somewhere I think I read something about it being close to 6th order bandpass.

Anyway. My point in mentioning karlson is that every solution will be evaluated (and multi driver karlson enclosures have measured favourably in regards to freq response and off axis dispersion). No matter what the end design will be it is bound to have some varying degree of compromise.
 
Some drivers I can get "locally" are the Fane Sovereign 12-200 (almost silly spl curve for a 12") and the Fane Sovereign PRO 15-600LF (thumbsup?) , and also the Fane Sovereign 18-500. There is a lot to choose from when going more expensive, or lower sensitivity drivers, but these are some of the very few that get close. That they come from the same factory must be coincidental.

If ordering from other countries I have to pay an extra almost 30 euro + 25% tax (tax is also on shipping), but some of the prices from sites such as bluearan seem very good, but I am a bit wary of the spec sheets on p audio drivers, as the spl curves must be tampered with ( almost all of the ones I've seen show at or over 100db/w irrespective of what it says in the text)
P-Audio :: P Audio E15-300S 15 Inch 300W Low Frequency Loudspeaker Driver Twin Pack 130.70

Seems like a good price at 130£ for two.

Regarding price. At least for me, I think the price must be under ca 180usd per woofer including shipping and tax to call it cheap, so max 360 usd for all the woofers total including everything. And maybe there should be some limit to stay below for the tops also, maybe 200 usd for all other drivers including shipping and tax. (no need for xo components except caps for tweeter protection)
 
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A Karlson cabinet is not the equal to a standard BR because much of the Helmholtz resonator volume is taken up by the front chamber, reducing low frequency output compared to net volume.

I know that. I was speaking of the spl and you can't get any more in the bass than from a BR-setup.

Kaffiman has requested flat frequency response, not what a Karlson is known for, the "slam" and so forth used to describe them are due to the elevated upper mid bass associated with the front chamber band pass.

I know that too. ;) I didn't go further into it because for his setup he isn't getting any advantages over a 'simple' Helmholtz system since it's limit in the bass is the same as a BR box - stating that, I thought it would already be clear it's not worth the effort and the other disadvantages.
 
Some drivers I can get "locally" are the Fane Sovereign 12-200 (almost silly spl curve for a 12") and the Fane Sovereign PRO 15-600LF (thumbsup?) , and also the Fane Sovereign 18-500.

The Fane are good and very good value for the money. I've simulated all drivers. A double Souvereign 12-200 setup goes not all the way flat down to 40Hz, a single one does though (in ~200l) but I think you want more 'grunt'. :D I would avoid the Sovereign 18-500, it isn't very good in your setup, the very high Qts makes it more suitable for a closed box ([email protected], slowly falling slope though). The Fane Sovereign PRO 15-600LF would be my preferred choice, would fit perfect for your needs.

[...] but I am a bit wary of the spec sheets on p audio drivers, as the spl curves must be tampered with ( almost all of the ones I've seen show at or over 100db/w irrespective of what it says in the text)
P-Audio :: P Audio E15-300S 15 Inch 300W Low Frequency Loudspeaker Driver Twin Pack 130.70

The P.Audio measurements are taken with caution. Part of it is because of the measurement enviroment, part because of smoothing etc. and the fact that the diagrams are created in different ways. Eminence's and Monacor diagrams are the only ones which are worse I know of. :D Despite that, the Eminence drivers are good value for the money too.
 
The Fane are good and very good value for the money. I've simulated all drivers. A double Souvereign 12-200 setup goes not all the way flat down to 40Hz, a single one does though (in ~200l) but I think you want more 'grunt'. :D I would avoid the Sovereign 18-500, it isn't very good in your setup, the very high Qts makes it more suitable for a closed box ([email protected], slowly falling slope though). The Fane Sovereign PRO 15-600LF would be my preferred choice, would fit perfect for your needs.



The P.Audio measurements are taken with caution. Part of it is because of the measurement enviroment, part because of smoothing etc. and the fact that the diagrams are created in different ways. Eminence's and Monacor diagrams are the only ones which are worse I know of. :D Despite that, the Eminence drivers are good value for the money too.

No doubt that Eminence drivers are good, but most of the interesting ones are not relevant at the moment because of import prices. Many good ones at ~95db/2.83 though.

It seems we can get a collective thumbsup on the Fane Sovereign PRO 15-600LF then, it was my personal favourite as well. :) seems like it has good build quality.

Allright, so Fane Pro15-600LF for low end. Good :)

But what about top end? At 100$/channel there might be some difficulties with mid drivers, maybe someone know any 6-8" high sensitivity ones for doubling them up with a compression driver? Maybe it's better to use a big wideband driver and a bullet tweeter crossed 1st order high up?