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Design or use someone else's? This is what I'm looking for.

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  • JRT
    commented on 's reply
    I suspect that notion of nominal playback levels which do not seem loud to you might not be considering the demands of higher crest factor in higher quality highly dynamic recordings. Highly compressed material may not have such difficult requirements, even when played seemingly loud.

    I would suggest against sizing the SPL capabilities based on nominal playback levels, but rather to accomodate the worst case maximum crests in the program materials, however brief, unclipped in both the electronics and in the electro-mechanicals.

    Recordings with less dynamic compression can have higher crest factor, may sound less loud on average while exhibiting higher crests in the signal. Because those are less loud, the listener will tend to turn up the playback level to hear the recording, and near 0_dB crests are raised similarly.

    The monitoring reference level utilized when mastering varies among recordings. Highly compressed loud recordings have lower maximum crests.

    The playback level that will sound more correct relative to what was intended would be the same level as was used in monitoring the mastering effort, but that level is rarely if ever disclosed by the publisher. So you are left to guess on playback. However in establishing system design requirements, you can look at worst case (which is arguably the playback of the best engineered highly dynamic recordings).

    For high quality recordings, Ioan Allen of Dolby Labs and Bob Katz (author of Mastering Audio, the Art and Science) both have recommended mastering with monitoring reference level of 86_dBC at -20_dBFS signal level summed uncorrelated at the listening position, which means 103_dBC at the listening position at 0_dBFS from each of a pair measured separately. Nominal playback listening levels can be much lower, depending much on what is appropriate for the program material, but a high quality playback system should accomodate 0_dBFS crests, however brief, unclipped.

    Near the top of the recorded spectrum, crests can exceed 0_dBFS by as much as +3_dB, at peaks between samples at frequencies near half of the sample rate (theoretical max is +4_dB, but that not achievable with practicable anti-aliasing filters which keep aliased content below the noise floor). Averaged power requirements are lower at high frequencies in music, but peak signal voltage can be highest there, though very briefly.

  • djg
    replied
    This should definitely keep you busy, the XO in progress. With budget options.

    Click image for larger version  Name:	Isiris WIP BOM May SS.jpg Views:	0 Size:	104.4 KB ID:	1487142

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  • tktran
    replied
    Jon Marsh @HT Guide is doing a large 3 way with dual Dayton 12" woofers- RSS315HFA-8, Purifi 6.5" 4 ohm midrange, and Bliesma 104mm faceplate tweeter per side. With facetted cabinets for diffraction reduction.

    This should keep you busy. This would be the large speaker I'd build if, I had to time to do my own cabinetry, or I didn't design my own speakers. He's a big believer is distortion data, and chose the lowest distortion driver in the bands that he uses. I have my own Johnny come lately large 3 way, but it uses NLA drivers.

    Leave a comment:


  • djg
    commented on 's reply
    Are you planning on positioning these up against the wall?

  • icor1031
    replied
    Originally posted by djg View Post
    Here's a sealed 3 way with good components by a competent designer. Component kit available from a U. S. source. You'll spend a significant amount on veneer. I'd like to see someone build these. The Zaph designs I've built were all quite nice.

    http://www.zaphaudio.com/SB12.3/
    There's no distortion data, but that seems very close to what I'm aiming for! I like it. I wonder though if anyone has a similar design, but with higher-quality drivers? Basically I'm going to have more money than time, so I want to get this close to perfect the first time; I want to avoid doing multiple builds.

    Leave a comment:


  • icor1031
    replied
    Originally posted by DeZZar View Post

    So I assume from your comments that this is really a music focussed system with theatre perhaps a secondary duty?



    And for good reason. Is there any specific reason you are limiting your choices to sealed?

    If money isn't an issue it would be difficult to do better than one of the designs from Troels.

    Troels SBA-741 for instance (http://www.troelsgravesen.dk/SBA-741.htm) is designed with an optional bass module - but can and is intended to be built on its own. It will 'only' perform down into the mid/high 40's in this format and is a good candidate for pairing up with an existing sub.

    I work with same drivers a lot and can simply say that you couldn't go wrong with this design.

    You could of course up the price point another notch and go for the equivalent scan speak version (http://www.troelsgravesen.dk/Ellipticor-3.htm) - this is end game level hifi for the greater majority of people.

    Troels SBA-941 (http://www.troelsgravesen.dk/SBA-941.htm) is another option. I'm currently working on a design for a customer that uses the same drivers in a similar configuration (sort of a nod to the box speaker/ATC classic style) and the sound is impressive. It dips down into the low 30's and arguably doesn't need a sub-woofer but it is an option depending on what sort of style you are going for.

    Just note that you don't need a speaker that is limited to playing say 60hz and above in order to use it in conjunction with a subwoofer. Any speaker can be used in conjunction with a subwoofer (or many subwoofers for that matter). A speaker that plays full range gives you the option to also listen without a sub.


    Music and movies; I don't like using a center channel even for movies.

    Sealed because ported limits placement options. And because IIRC, sealed produces less linear distortion... And I didn't mean that the mains could only be effective to 60, I meant that I wanted them to be *at least* effective to 60. Because that's where I'd prefer to cross.

    Thanks for the speaker suggestions, I'll check them out.

    Leave a comment:


  • djg
    replied
    Jeff Bagby's Continuum or Kairos with his separate bass module would give you a two piece 3 way. Component kits available elsewhere.

    Leave a comment:


  • djg
    replied
    Here's a sealed 3 way with good components by a competent designer. Component kit available from a U. S. source. You'll spend a significant amount on veneer. I'd like to see someone build these. The Zaph designs I've built were all quite nice.

    http://www.zaphaudio.com/SB12.3/

    Leave a comment:


  • icor1031
    commented on 's reply
    The ones I built a decade ago with help here... I think it was paper woofer, silk tweeter. 5.25" and 1.125" as I recall. Peerless? Room would be living room.

  • icor1031
    replied
    Originally posted by ugly woofer View Post
    Icor, would you walk into a shop and pick out a speaker without listening to it? That's the equivalent of building a kit that you have never heard, I don't care who designed it. Just because it's a competent design or others recommend it, doesn't mean that you will like it in the long run. So yes, go to a meet, Iowa would probably be the closest, and have a real listen
    Possibly, based on reviews, response and distortion graphs. Unwise? Maybe so. I haven't experienced enough to say.

    But anyway, I'm moving to Gainesville, FL. ASAP. Which meet is closest to there?

    Off to an appointment, will reply to others later.

    Leave a comment:


  • ugly woofer
    replied
    Icor, would you walk into a shop and pick out a speaker without listening to it? That's the equivalent of building a kit that you have never heard, I don't care who designed it. Just because it's a competent design or others recommend it, doesn't mean that you will like it in the long run. So yes, go to a meet, Iowa would probably be the closest, and have a real listen

    Leave a comment:


  • donradick
    replied
    If you like to listen at lower volumes, a little known fact is that a high Qms mid or mid-woofer will reveal more micro details. I have a lot of experience with Dayton RSS woofers and some with SB acoustics woofers, but I was shocked when I built a Criton 1TD pair for a friend (from css audio). The amount of detail and clarity blew me away! It's because the LDW7 woofers have high Qms values. I prefer 3 ways, but I didn't feel that I was missing anything in the mids with this design. Sorry, I can't drop a link here.

    Leave a comment:


  • DeZZar
    replied
    Originally posted by icor1031 View Post
    They will be used for front-left and front-right only. I will not be using a center channel.
    So I assume from your comments that this is really a music focussed system with theatre perhaps a secondary duty?

    Originally posted by icor1031 View Post
    It seems though that he [Troels] has few, if any, sealed designs?
    And for good reason. Is there any specific reason you are limiting your choices to sealed?

    If money isn't an issue it would be difficult to do better than one of the designs from Troels.

    Troels SBA-741 for instance (http://www.troelsgravesen.dk/SBA-741.htm) is designed with an optional bass module - but can and is intended to be built on its own. It will 'only' perform down into the mid/high 40's in this format and is a good candidate for pairing up with an existing sub.

    I work with same drivers a lot and can simply say that you couldn't go wrong with this design.

    You could of course up the price point another notch and go for the equivalent scan speak version (http://www.troelsgravesen.dk/Ellipticor-3.htm) - this is end game level hifi for the greater majority of people.

    Troels SBA-941 (http://www.troelsgravesen.dk/SBA-941.htm) is another option. I'm currently working on a design for a customer that uses the same drivers in a similar configuration (sort of a nod to the box speaker/ATC classic style) and the sound is impressive. It dips down into the low 30's and arguably doesn't need a sub-woofer but it is an option depending on what sort of style you are going for.

    Just note that you don't need a speaker that is limited to playing say 60hz and above in order to use it in conjunction with a subwoofer. Any speaker can be used in conjunction with a subwoofer (or many subwoofers for that matter). A speaker that plays full range gives you the option to also listen without a sub.



    Leave a comment:


  • fpitas
    replied
    Originally posted by tktran View Post
    Most people who have designed their own have had a decade or more of experience building speakers.
    Even then it's a labor of love. It's a great hobby, but I think designing your own is for those who want the challenge. If you just want great speakers there are farrrr easier ways.

    Leave a comment:


  • tktran
    replied
    what speakers are you used to? What do you have now? What’s your favourite type of music, please describe the room you gonna put it in? Do you have a Music, acoustics, or engineering background?

    I concur with other people‘s thoughts you should build an established design, don’t design your own, unless you want wanna play around. If you want something that sounds good then build an established design. My recommendation would to build one of Wolf’s designs, Curt’s designs, or Dennis’s designs
    there are probably more but what we designers know if that it takes good science to figure out the stuff that’s known, and good ears to figure out what we are yet to know,

    Most people who have designed their own have had a decade or more of experience building speakers.

    Leave a comment:

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