I'm of the school crossovers are as important as drivers...
Yes so very true. And that is where the use of L-pads come in.They help you tune the speaker sound to the room.But the most important part IMO&E is your measurements will help you to build a perfect crossover for your particular speakers.With your measurements and impedance plots and T/S parameters of your speakers, if you have them ? You can build a spot on crossover instead of using a universal crossover like an 500 Hz,800 Hz,1200 Hz,etc, Crossover..Originally Posted by alancohen
I'm of the school crossovers are as important as drivers...
Your neighbors called. They like your music.
You're welcome! Yes, rear panel removal to tweak sucks, so initially I used carriage bolts, wing-nuts and access panels, but due to cab weight and life long back issues, I finally switched to fixed/glued backs to increase cab rigidity and removable driver baffles a couple of years before Altec did on the 846B. Since the local distributor's in-house design team was aware of this and other tweaks I was doing............
Really, consumer cabs for the most part are just so-so furniture construction with mediocre audio performance, so consider either getting 'new' components and/or at least using what's in the Heathkit cabs and DIYing some cabs more appropriate for your new room's acoustics.
1 m measurements are fine for designing XOs and comparing different speakers, but this current obsession in the DIY community with billiard table flat responses at raw data to 24 dB/octave smoothing just because they can when no normal human can hear better than ~6 dB/octave resolution and will be much further away in an acoustically small room is not the best overall choice unless one sits at < 1m from the speakers in an acoustically large enough O.B. located outside on an open/flat field or similar.
Not familiar with Jim Smith's work, but unless it's very current and a thousand or two pages I suggest Googling for room acoustics websites and browsing the various DIY audio forums for DIYing room treatments to fill it out somewhat, though using horns with the proper polar response, speakers and listening position for the room, etc., treatments other than carpet or area rugs typically aren't required since LEDE rooms are best overall for horn and other 'focused' systems.
GM
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
More so actually, along with cab design/construction since some of the world's most expensive, best reviewed super-fi speakers use inexpensive, 'plain vanilla' drivers available to the DIYer except with their markings to garner exorbitant replacement parts pricing. Up to a point then, thanks to our typical hearing acuity not being all that good combined with our penchant for preferring most things 'rich', be it visual, taste, feel, hear, we can be fooled into believing you really can make a 'silk purse out of a sow's ear'.
GM
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
Apology not necessary Volvo !But Thanks, I appreciate that ! I was just trying to keep it on track as he has put a lot of work and expense into this.And would like to see him arrive to that perfect Altecness ! You know the one ? Where you have that grin from ear to ear,kinda like this guy ---->
And as why I only ever go to 1/6 smoothing. It's good enough.
Now here's a good point. Ultimately, I will be using a Behringer DCX2496 active crossover and biamping.
Those little black boxes on top of my Heathkit in the previous pic are (8) 300B tubes. I'm patiently waiting for the kits to start building (2) 300B OTL monoblocks to drive the horns.
So realistically, I will not have any components in between the 300B cathodes and the 802G drivers. No output transformers, capacitors, inductors or resistors. Mmmm...
So I watched Jim Smith's DVD and started reading his manual, "Get Better Sound". He seems to be a very hands-on guys, with decades of experience setting up rooms for speaker manufacturers at trade shows like: Acoustic Research Corp, Magnepan, Dahlquist and Advent as well as running his own audio shop in Atlanta for years where he has personally set up hundreds of systems. His claim to fame is being able to set up a room to get the best possible sound. He currently works as a consultant for hire, where he will come out and analyze your room and set it up for you.
His thing is more about working with the room rather than overtreating it. He does advocate well placed diffusing and absorbing panels, but spends most of his effort "finding the best bass" in the room and setting up the speakers and "THE" listening chair in exactly, and I mean exactly, the right position where the "sound just pops and the walls and speakers disappear". His mantra is, "If you don't get the bass right, you'll never be happy with your system". He advocates taking the time to get the best out of the system you have and have it "play the room" before you even think of buying a new component. His claim is the room is the most important component in your system.
Like has been mentioned here before, he believes the "out of context" frequency response of a speaker is irrelevant. After all, most speaker manufactures are pretty good at making speakers. It's what happens to the sound in real time in a room that matters. Peaks and suck outs can be enhanced or eliminated depending on where you and your components are located. He uses gaffer tape to set up a grid on the floor and a laser tape measure to perfectly align everything. He uses specific reference CDs that he knows well. He speaks of a certain chime at a specific part of a particular song that is supposed to be located just inside the right speaker of the stereo image. If the right speaker is located even as much as 2" too close to the listener, the chime will be more centered.
He cited one system that he had set up where the customer called him back after a couple of months noting that the mid bass had become mushy. When he got there, sure enough he measured a 6dB peak around 100Hz, I think. He measured forward of the listening area a foot and it disappeared. He thought that odd since nothing had been moved. His marks were still on the floor. So he moved the sofa up a foot and the the peak was back, but had disappeared 12" back where they started. This was puzzling at first, but then he noticed from his notes, that the sofa was different. The customer had bought a new one. It was leather with a firm back panel that was found to be resonating at 100Hz. They damped the sofa back and the peak was gone.
Now this might be all well and good, but he's using "conventional" two and three way "tweeter" loaded speakers. He likes Vandersteens to give you a reference. But I'm curious as how all this relates to horns. I do notice an uptick in image when I get my head perfectly centered between my Heathkits, but I get a nice stereo image throughout most of the room as well.
So how directional are Altec horns compared to "conventional" speakers? And if there is something to this, do I need to either get them off the floor or tilt them up a bit?
As far as this "sound just pops and the walls and speakers disappear" stuff, I think mine do that already. If I close my eyes while listening to a well recorded piece of music, the sound stage is huge and I can pick out every instrument in the band and where they are sitting (or at least where the engineer has them sitting). But I will need to "get the bass right" in the new place before anything. I hope the best bass is in a place I can live with. I will not have a dedicated listening room.
BTW, here's an article where Jim won the 2001 Soundstage Reviewers Choice Award while working for Avantgarde. He had a day to set up the room that was supposed to have 3 rows of 3 seats each for listening. He realized that was impossible due to the acoustics of the room and strong-armed the powers that be to setting up with only 1 row of three, 'cuz that's where the right bass was. Of course this meant a lot less people would get to listen and it was a very risky play, but it worked. People were lined up all day to hear the Duos and he won the award.
http://www.soundstage.com/earmarked/earmarked200110.htm
Last edited by alancohen; December 16th, 2012 at 08:44 PM.
It depends on which Altec horns you're discussing. Altec Mantaray horns have a relatively large "sweet spot" whereas the 811b horns that you own have a relatively narrow sweet spot. Most "audiophiles" who own Altec sectoral horns like the 811b's "toe them out" slightly to get the best dispersion pattern relative to the listening spot that they're "aiming" at. In other words, if your listening spot is back a ways from the speakers and centered between the two speakers--rather than pointing both speakers right at your head, ideally you would want to point the right speaker more towards (and maybe even slightly right of) your right shoulder and the left speaker towards or just left of your left shoulder. Trial and error/experimentation is your friend here/YMMV...
As far as your other question, yes, you should either build risers for your AS 101's or prop up the fronts IMHO. Valencias (and AS 101's) are sometimes called "low boys" as they are not very tall and sound great if you sit on the floor! If you're sitting on a couch etc. they will sound noticeably better either on risers or with the fronts propped up. Putting them on risers or propping them up will help the horns to be pointed at ear level, but will also affect the bass response. Some people swear by risers, and some don't like what having the speakers that far off of the floor does to the bass response. No matter what theories or measurable phenomenon are in play in this regard, in the end it really depends on your room acoustics and your personal taste as far as what sounds "best". Same thing for propping up the fronts of the speakers. Some people don't like what that does to the bass response, and some swear by it.... FWIW, Altec 416's have great low end and shouldn't rely on the floor for bass anyways (with either of these two proposed set up options) IMHO....
Last edited by voice of the theater; December 17th, 2012 at 10:03 AM.
Being of "Sound" Mind
Thanks VOTT. I'm learning more and more every day!! And the sound is getting better too.
I just tilted them to see and yes, I like it better. Bass is not an issue. The right bass is. More is definitely not always better.
I finally closed on the house yesterday. Whew! Here is a pic of the room I will be setting up in. Or I should say two or three rooms.
My initial thought is to have the speakers against the far wall and my personal listening chair on the other side of the fireplace. Yes, I will have to treat the stone behind my head. The floor they will be on is built up and could be have resonant vibration issues. I will have to wait till I get everything in to measure. I might have a problem. The double glass doors on the right will be a first reflection problem as well. Heavy drapes I'm thinking. I could open them up little by little and see where the best sound is. There is also a cathedral ceiling in that area. That will have to be treated as well.
So I will likely build risers with floor spikes or some other vibration isolation for the time being. It will certainly be an adventure. My big decision is whether to incorporate my home theater or keep audio separate. Decisions, decisions...
More pics of the space...
Last edited by alancohen; December 18th, 2012 at 08:50 AM.
Wow--congrats on the new house Alan--it is gorgeous! Glad to hear it's in a quiet neighborhood too--I'm sure you won't miss the constant noise that you mentioned in your old neighborhood. I like your proposed set up plan and I think you're asking all the right questions/have some good ideas as far as heavy drapes for the glass door etc. Yes, the ceiling, floor, and fireplace may be issues--you'll most likely hear the answer to those questions as soon as you crank up your Altecs in that room. Being a professional musician, I've always been fortunate enough to achieve great results doing everything by ear with my three Altec systems as far as set up and tweaking/fine tuning the speakers and the room (largely thanks to help/advice from many good people here), but of course measuring can be a good tool as well. My band has played in rooms with cathedral ceilings, and (untreated) they can add an unbelievable amount of reverb to your sound (not a good thing!). As far as your hardwood floor, an area rug (and maybe tilting the speakers or some risers?) can do wonders...
As far as your home theater debate, two of my Altec systems are not only used for audio, but are also connected to blu-ray players/satellite TV DVR's, and 50" plasma TV's. I love the way movies and music "videos" (DVD/Blu-ray/Satellite TV Broadcasts) sound over my Altec systems, and would consider it a waste to try to enjoy those things with inferior speakers. I'll be interested to hear what you end up doing with your room as far as sound treatments, as well as what you do with your Altecs/crossovers/risers (or tilting)/etc. (and whether or not you incorporate your home theater with your Altecs).....
Last edited by voice of the theater; December 18th, 2012 at 10:11 AM.
Being of "Sound" Mind
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