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Posted by atilsley169 on
06-06-2012
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fiogf49gjkf0d
Hi Romy…and fellow audio nutters.
I’ve bitten the bullet, and shifted from BLH to front-loaded. Yes, I was an idiot, a moron for not doing this sooner.
My project is ‘humble’ by Romy’s standard…but I feel it meets the following objectives I have set:
1) A 4 or 5 way horn system, with all speakers being front loaded
2) Costs contained as best as possible
3) Cabinets that enable me to have some DIY input
4) Use of compression driver for the 500-5,000 range
5) Retain the use of my valve amp (2A3 Push Pull) where possible, but may go active down the track
System layout:
Sub is Bill Fitzmaurice Tuba (Low Profile) running up to 90-100Hz. I have the O-Audio 300 watt BASH amp for this. Quite a big sound.
Mid bass is DIY based on a John Inlow drawing, features B&C 12-inch driver (PE32), 101dB, low qts of 0.18. I will run this up to 500/550Hz. See pics of the early stages of this build.
Mid tractrix horn is Stereolabs stone composite 250Hz, using Selenium D405 driver. These have been ordered from Germany….mid blue in colour. (Are you cringing because of these drivers? Well, it's a start. Would I like S2's, ALE, GOTO, TAD...? For sure.)
HF is Sterolabs tractrix 1,000Hz horn, using Selenium D220TI, running from 5,000Hz.
Having recently built a two-way ‘Klipsch’ “Cornscala” (Bob Crites design, using Faital Pro 1.4 inch driver and Eminence 15-inch woofer), I decided to use Bob to build some custom xovers.
My amp is a new Weston Acoustics 2A3 push-pull (similar here), with approx. 9-10 watts RMS/side (x2 2A3’s per channel). I love the amp…so I wish to retain this for driving the horns (except sub).
Source is no frills CD/DVD player with DIYEDEN DAC. Simple but quality silver cables throughout…including all silver speaker wiring, but silver over copper for interconnects.
Music choice is blues, jazz, funk…not a lot of classical.
Kind regards
Andrew
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Posted by Romy the Cat on
06-06-2012
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fiogf49gjkf0d
Hi, Andrew
Yes, the move from BLH to front-loaded is a large move but besides everything it is a very drastic way to review HOW the channels are positioned relative to each other and relative to the room. With front-loading the subject of phasing become critical. With BLH the phasing is so fucked up that there is no real needs to think about it as you are in absolute mess. It is like a symphonic orchestra with musicians sit all over the concert hall, 100s feet from each other and in random locations – there is no such a thing in this condition as to “play together”. If you however, arrange the musicians in proper section and position section in proper location then the subject of “timing” or the subject “when to start playing” because important.
It looks like you did not figure out how to use the posting interface as your text is corrupted (I might fix it) and your images did not go through. It is hard to recognize what you are trying to do without the pictures. Anyhow, a few comments regarding to what you have exposed.
Your LF section, the Tuba by Bill Fitzmaurice. I do not know what it is. I hate Bill Fitzmaurice and consider him being an idiot and I truly do not pay attention to any brain defecation that come under him. So, I can’t not judge or care what Tuba. The O-Audio 300 BASH amp that you use to drive your LF section is a controversial subject but there is a lot more to it then juts the amp.
The John Inlow’s paper horn are great. I do not use them and from the purist position I do not endorse them but I do admit that the paper mache horn that John Inlow advocate is wonderful idea. I have a few friends who built the paper horn years back and I very much like the concept. The key in it is to find some kind of prime according to which the mass and the resonance of the horn would be somehow “talk” with the horn rate and the driver’s primary resonance. If to tune it in the way how musical instruments are being tuned then it is possible to built an ultra-light, self-damping horn where the lightness of the horn will not be negative factor, or to be even a positive factor. I do not see anybody talk or look into it and the folks who experiment with paper horns feel that they make “poor man horns” but I do feel that with proper level of seriousness the direction is very perspective.
The Stereolabs 250Hz horn and Selenium D405 drivers. Am I cringing? Why shall I? I never had that Selenium 405 driver and do not know anything about it, so I have no reasons to like or do not like it. The same goes to the Selenium D220TI - I never seen it.
The Cat
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Posted by atilsley169 on
06-06-2012
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fiogf49gjkf0d Thanks
For some reason, I can't attach pics. I use the attach key, but when I post, nothing happens...sorry.
Here's some pics on Stereonet (in Australia) with my build pics.
My comment re you cringing over Selenium, is that these are cheapish...nothing like the mid or high end gear.
The Tuba sub could make its way into my dedicated HT room.....and it does sound truly frightening for sic-fi and other movie tracks.
I've built tapped horns in the past...so may go back to that...not sure.
Am I loosing out a lot by retaining passive xover?
Andrew
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Posted by atilsley169 on
06-06-2012
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fiogf49gjkf0d Oh, btw, I've built some bass horns for Ming Su....see link.
A lot of my projects use CNC'd layers of MDF or ply.
http://www.audiovoice-acoustics.com/forum/showthread.php?t=932
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Posted by atilsley169 on
06-06-2012
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fiogf49gjkf0d Here's a pic (link) of my listening position.
When I built my large Bill Fitzmaurice bass horn...I had thought about placing it in that space above the speakers, firing into the corner. I may still do that...but the sub is serving duties in the separate HT room.
So, I may design a new large bass horn, using a single driver, with the horn firing down towards the left corner.
A mate did a quick sim for me on a 6.2 meter ( 21 feet) horn with mouth size of 11,025cm (45cm deep by 245cm wide, [96 inches wide x 18 inches deep for your imperials). The sim didn't look nice at all...very ragged.
But, there must be something 'fun' I can do to fill that void...and get a smooth response from 25Hz to 100...?
What about two tapped horns...on top of each other with horn openings oposing...?
Alternatively, a single(?) LF channel comprising, say, 8 x 12 or 15 inch woofers in a sealed panel/cabinet...?
However, I wouldn't mind ideas on drawing up a horn I could build.
Thoughts?
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Posted by atilsley169 on
06-07-2012
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fiogf49gjkf0d Thanks Romy
I appreciate your advice re non single bass horn.
When you say, 'good luck with a smooth response from 25Hz,'...does that mean it's not possible to get a smooth response...or, it's not so important to get a smooth response...?
A friend sim'd one of the large horns...and the plot looked very ragged. Is this what you mean by non smooth response? (Just trying to get my head around the terminology.)
For dual sub horns....can you suggest a profile I can work with...?
For example, with the space I have, I could accommodate two horns with horn length of 95-100 inches, with mouth size (rectangular) of 40 inches by 20 inches. I would take advice re driver selection....10, 12, 15?
Thanks and regards.
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Posted by atilsley169 on
06-07-2012
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fiogf49gjkf0d Midd bass horn in initial build stage
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Posted by atilsley169 on
06-07-2012
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fiogf49gjkf0d Mid bass
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Posted by atilsley169 on
06-07-2012
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fiogf49gjkf0d More mid bass pics.
Note - I will bulk up the horn wall thickness considerably, by adding another 2-3 layers of MDF and/or Ply.
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Posted by atilsley169 on
06-07-2012
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fiogf49gjkf0d Drawing of dual LF bass horn.
Romy, here's a sketch of how I might be able to build the LF bass horns...per my post above.
Regards.
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Posted by atilsley169 on
06-09-2012
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fiogf49gjkf0d Further wood added
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Posted by atilsley169 on
06-09-2012
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fiogf49gjkf0d
A friend was earlier talking about dsp....I was shy of it...thought it too hard.
Now...I saw this -
http://www.decware.com/newsite/zkit2.htm
Suddenly...it all fits.
4 boards to run the top horns (SET)...good.
Then, a Krown power unit to run the bass horns....6 lines in all.
How do I then look after the output.....? Purpose built pre?
Thoughts?
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Posted by atilsley169 on
06-10-2012
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fiogf49gjkf0d
Today, I tidied up edges....built baffles in glued up 25 nn ply...added rounded Tassie Oak edges....filled inside.....getting there
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Posted by atilsley169 on
06-11-2012
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fiogf49gjkf0d Baffle added in 25 Ply....holes later filled with putty
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Posted by atilsley169 on
06-15-2012
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fiogf49gjkf0d Romy
With the height, I plan to have the mid horn set around 1200mm with tweeter below, eg 900mm.
These will reside on a timber or metal stand I'll fabrecate miself.
What are some important considerations here?
Regards
The Andrew
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Posted by Romy the Cat on
06-15-2012
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fiogf49gjkf0d I’m sorry, Andrew but I have absolutely no idea what you do and what you are asking. You make many posts and uploaded many pictures but they are all absolutely irrelevant as you did not clearly explained what you are doing and what you objectives are. You might have some kind of plan in your head but no one reads your mind and until you clearly express what you do no one will be able to give you any worthy recommendations. Reciting the drives and horn rates is not the indication of acoustic system or acoustic system’s intend. So, ether provide good illustration of what you do or do not anticipate sensible answers to your questions.
The Cat
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Posted by atilsley169 on
06-15-2012
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fiogf49gjkf0d Thanks The Cat
I'm posting the pics of the build as I progress so people can see and pass on ideas, that's all. Are you suggesting you don't want horn projects shown on your site? I had earlier outlined the design, including cross-over points etc.
I assume people can see what I'm doing...and so assist as they feel they can. Although I've built a few speakers for Tannoys, Altec, Klipsch and Lowther...this is my first true front loaded system...so I'm keen for as much support as I can get...
Now I'm asking a general question about the hieght of the mane mid horn (500Hz to 5,000Hz). I'd appreciate your thoughts on this...as I understand this is one of the most important aspects of the horn system.
As you suggest, I'll prepare a drawing as well.
Also, FYI and for discussion later, I am swapping my 2A3 Push Pull for 3 separate stereo amps to run the horns. I will have two 6L6 SETs for the mid and high horns, plus a PP 6V6 amp for the midd=bass. Each of the three amps will have separate volume controls, with one having a master volume. Cross-over is undecided.
I'm yet to decide on final sub bass...but am looking at dual 30Hz tapped horns. The amps are from Oz builder, Earle Weston, who is meticulous...and hand winds own tranformers.
Kind regards...and thanks four yor helps.
The Andrew
(Oh, how do I post a pic that shows in the body of the email? Thanks)
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Posted by atilsley169 on
06-16-2012
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fiogf49gjkf0d Hi The Cat
I forgott to answer your q, what I do.
I 'do' management...heading up a team of folk for a large social services charity in Sydney. I cover training, occ health and safety, payroll, volunteering etc. We have 2000 staff.
My interest in audio stemmed from building BLH's...Lowther, Fostex, Corel, Visaton etc.
I've developed CNC design to help build the more complex internal horn structures.
Lately, I've enjoyed a two-way speaker from Bob Crites (USA Klipsch enthusiast)...hopefully, and unlike Bill Fitzmaurice, Bob isn't on your douche-bag last. I've also built some contacts with the guys at Great Planes (are they OK?).
I've built horns for Jim Carfrae and Ming Su (US GOTO Rep).
I'm just an enthusiast...and I lug speakers around Sydney to various crappy hi-fi events to promote horns....why? Not commercial...but for the passion.
So, I post here to get ideas and share ideas...all I'm asking for is ENGAGEMENET with you and others....
Thanks fro your asstance.
Kind regards
The Andrew
PS, what do you do?
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Posted by Paul S on
06-16-2012
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fiogf49gjkf0d Hi, Andrew
You seem like a nice, sincere guy, and I hate to see you dangling. Perhaps, at the least, you might want to read more of the site contents, to see if you can get a better feel for "what goes on here". In the "what you do" instance, the question regards your objectives, sonic/musical versus implementations. Basically, you are being asked to to bring others up to speed on your particular situation, not just with pictures and verbal descriptions of the parts, but also what you are getting from these works in terms of sound/music, what "problems" you are trying to solve, and/or where you'd like to go from here in terms of sound/music.
If nothing else, this site is a vast Library of Sound Methods, and it is quite likely that close reading will even provide useful insights into your own situation. In the meantime, be advised that "BLH" is another non-starter around here, not likely to draw much interest, except subject to friendly fire if pressed.
Best regards,
Paul S
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Posted by atilsley169 on
06-16-2012
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fiogf49gjkf0d Thanks Paul...yes, I've already come clean that I'm a moron for getting into BLH's....! (However, at least that got me into horns!)
Your other points are valid.
I fear I don't have a lot of technical and nuanced answers up to Romy's standards though. I 'build and listen.' I know enough of what I want though...and I feel that this has already been outlined in my posts by listing the config, driver choice, horn choice, amps etc. Then, I simply seek some ENGAGEMENT along the way.
If the site, as you say, is more for a repository of technical papers, and less a site for sharing projects....fine....but I'm not going to be put down or bagged out because I'm at least giving a 'proper' sound system a go!
Cheers.
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Posted by Paul S on
06-16-2012
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fiogf49gjkf0d It's not the "technical" stuff that's being solicited here, rather it is your sonic objectives laid out in plain, simple terms. Looking at the "stuff" is not enough, especially if no one knows how it sounds to you, or how you want it to sound. What good is "advice" about driver height off the floor, for example, if particular objectives and/or frustrations are not spelled out? Don't worry about "technical" knowledge, or "good grammar", for that matter. Just say what you hear, what you like, what you don't like, and what you want to hear. This will bring your pictures into perspective.
To kick this just once more in the right direction, but without going back to look at the pictures for reference, I would suppose that the sound is not especially Musically forceful or saturated, due to the limits of the drivers, themselves. On the face of it, this seems to favor the "headphones" approach.
Take it away, Andrew...
Best regards,
Paul S
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Posted by atilsley169 on
06-17-2012
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fiogf49gjkf0d Thanks Paul
I don't have the horns yet, so I can't comment on the sound. I bought them because of what I 'wanted' to hear....large scale dynamics. Friend has the avant-garde trios. I liked their presentation....but not their cost!
So my goals are:
Dynamic 'big' sound.
Detail.
Good response from approx 30hz.
Good balance of performance vs price (that's why I am building own mid bass horns and using drivers like selenium vs s2, goto, etc.
I've relied on Folk like John Inlow to enthuse me. Part of the game is sharing and being engaged with others, no?
I hope the cat hasn't got his kitty litter spilt over all of this.
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Posted by atilsley169 on
06-17-2012
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fiogf49gjkf0d In response to Romy's request re drawing, Here's a rough sketch to scale of the three-way.
Not shown, two folded tapped horns with will sit at either side of the mid bass horns. These won't be large...30/35Hz to 100.
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Posted by Romy the Cat on
06-17-2012
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fiogf49gjkf0d Ok, Andrew, this is allergy something. I would highly advise you in future before you post any discrete updates, questions, and ideas about what you to inform about the holistic objective of your project, sort of a view from 50.000 feet. That what I meant when I asked “what you do?”
About your project. I would encourage you to look for different location for your playback. The 6 feet is not the width where you will be able to host your inhalation of this topology as it will be underperform. Sure we all restricted by space but if you can find different location in your room them you might want to consider it.
So, the midbass rectangular horns are 100 to 500Hz. The lower MF horn from 500 to 5000 and the small horn cover from 5000 and up – let call it HF channel. The idea looks OK but the positioning of it very bad. If you have MF run to 5K and HF start in 5K then you shall not introduce any horizontal offset as it such high frequency you’ll have a lot of imaging smearing. I would very much advise to use the MF and HF horns in strictly vertical configuration. It might be a bit tricky in your case. You can drop you MF horn all the way down to upperbass and put HF above or you can locate the HF under the MF. In your configuration both will work but it would require some sensibility to do it in order to maintain the center image in right spot. I need more information to estimate HOW it might be done. The rate of the horns or the diameter of the mouths, the type of the drivers, the listening distance, the type of the crossovers, the high of midbass horn, the music you will be playing, the proximity to the back wall, the space behind your listening chair and etc…
Also, I would like to know what make you to propose to use the 500 to 5000 configuration but not any other configuration.
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