STL

---------------- On 1/29/2003 7:44:14 PM James D McCall wrote: You don't want the rear's position to be obvious, and the diffuse radiation of the RS's will help make sure they aren't. ---------------- I was under the impression that was true with Dolby Pro-Logic and with surround sound music, but not the case with Dolby Digital and DTS (movies).

So is this type (TH-SR-70) of Heresy speakers any different then your average consumer Heresy Is? If so, how?

Good point Keith! Smaller woofers do tend to produce better midrange (especially when the aren't muddied up trying to produce bass). That is part of the reason that I am using four 6.5" drivers (along with the K-85-K tweeter) to be the center for my KG5.5s front mains. The four 6.5" drivers should move roughly the same amount of air as the dual 10" woofers (in each KG5.5) but the smaller cone area should produce better midrange and mid-bass (and this better voices).

Yes, using the same model of bookshelf speaker each channel would ensure all of them are perfectly timbre matched! It still would not be quite as good as what Horn-Ed and I are doing since the bookshelf speakers would likely have to be set to "small" (thus they would not be producing the entire spectrum of sound).

---------------- On 1/27/2003 10:54:27 PM mmiles wrote: With all the threads lately about timbre matching, 75% of the sound is in the center channel etc. I wonder why no one has asked the guru's on this forum this question? With RF-3II as the mains why not RB-3II as the center and surrounds? Same for a RF-5II configuration. What about RB-xII's all the way around since I just upgraded my sub (SVS 2039pc+, see "BOOM BOOM out go the lights" posting)? I don't see RB-3II or RF-5II listed in the Klipsch website? I do see RB-3 and RF-5. Using RB-3 as a center to go with RF-3II mains would not be optimal. The RB-3 does not use the same tweeter, whereas the RC-3II does share the same tweeter (with the RF-3II). The same goes for the RB-5II and the RF-5. I do see where the RB-5II uses the same tweeter as the RF-3II...so that appears to be a better option.

www.avsforum.com

By electronic they mean active. Most home speakers have a passive crossovers which means the filtering is done on an already amplified signal (and the filter components do not get any outside power). An active crossover does the filtering before amplification and the filtering is done with op-amps and resistors (and such) and which are powered by an outside source. The disadvantage of active crossovers is that you need more amplifier channels. For instance a stereo setup that uses an active (2-way) crossover will need four discrete amplifiers. For car audio, it is very common to see active crossovers. IMHO, active crossovers work better for filtering between the bass and midrange and passives are fine (for the most part) for filtering between midrange and tweeters.

I have a pair of ESS AMT-1As (minus the tweeters) that need some work (because of rotted foam). I'm looking to sell them. Let me know if you're interested and I can email you some pics and more info...

Dammit Doug, I'm trying to get my brother-in-law to buy that (for a future home-made center channel)! Now with all this exposure the price is going to get jacked up!

Actually, I'd like to know this too! Anyone?

---------------- On 1/23/2003 4:02:12 PM redtop wrote: STL, After that last technical post on the woofer addition, I think you ARE an acoustical engineer... Stop screwing around with those electrons and ride the (sound) waves.... ---------------- Thanks! You know I REALLY wanted to be one, but I decided there was more job opportunity and therefore money in EE. During my senior year, I sent resumes to many audio companies but either heard nothing or got the typical "we'll keep you in mind" letter. It's just such a niche market (for engineers). I am doing "cool" work for an aerospace company -- so alias audio is just hobby.

I see the original SF-1 used a K-1075-K 6.5" woofer, but now it uses the K-1078-K 6.5" woofer. I also see that K-1078-K woofer was used in the SF-2 from the beginning. Why is the K-1075-K no longer used? Was is "not good enough" in some way? Also, how can the current SF-1 (using one K-1078-K) and the SF-2 (using two K-1078-Ks) both be rated at 8 ohms? That doesn't seem electrically possible.

I was under the impression it was more for looks rather than performance, but I wanted to see if anyone disagrees (and why). I noticed that my KG5.5s do not have flush mounted drivers.

Discrete or not, 6.1 is only going to widen the sweet spot for rear surround sounds, but if you are already sitting in the sweet spot (like I always do) then it is not really going to make a difference. Like others are saying, I wouldn't bother upgrading now!

---------------- On 1/23/2003 3:01:01 PM duckloads wrote: Would I do myself any good by adding a second woofer to my KSF-8.5's that I use as my mains? What would have to be done about the crossover? A new woofer is still avilable for around $90. ---------------- Not really IMHO. You could essentially make it into a KSF-10.5, but you would need to buy two new woofers for each speaker (and likely some new components for the crossover). The 8.5 and 10.5 do not share the same 8" woofer. By the time you spend that kind of money it really wouldn't be worth it. Klipsch lists they frequency response as the same (both going down to 36Hz) and the 10.5 is only 1dB more efficient.

---------------- On 1/23/2003 1:26:58 PM HornEd wrote: Timbre, essentially the "voice" of the speaker changes dramatically when speakers or ports are added or delted... or when cabinet volumes change substantially. That's why trying to match 40 lb CENTERS with 100 lb right and left MAINS and 25 lb SURROUND/sprayers... is a largely impossible task. ---------------- I am fully aware of that and I understand the acoustics behind the changes, but adding a second identical woofer correctly will not make a timbre mismatch! To do it right one would need to wire the woofers in series (so they will share the wattage) and that would lead to a fairly simple redesign of the low-pass section of the crossover since the impedance it would see would now be double of what it was before. Also to keep the vented enclosure tuned to the same frequency, you would have to add a port AND do one of the following: 1) change the length of the ports, 2) increase the internal volume of the enclosure, or 3) do a little of both 1 and 2. This would not change the timre at all and would likely make for cleaner midrange coming from those 8" woofers (since their cone excursion distance would be cut in half)!! I agree this would create a lot of extra work, but like I said it would also have benefits that would very substantial for a center channel speaker. If you don't agree, please explain. Maybe I am missing something, but I feel fairly confident that I have this one right.

---------------- On 1/22/2003 10:37:13 PM redtop wrote: I just wasn't sure how important the spacial relationships with the woofer, port, and horn are. I love my Klipsch and I don't want to be sloppy and screw this up. I want to do it right the first time. Actually port placement isn't a real big deal. Ideally you want the port located on the front baffle and as close to the speaker as possible (to get some coupling and thus a little more SPL). Keeping it on the front baffle and moving it on the other side of the tweeter isn't going to make much of a difference. The problem I have is that by using only one woofer the sonic center of your speaker might now be somewhere between your woofer and tweeter. I would try to mount them as close together as possible. It could be the weighting on the tweeter is so much higher that it should still be mounted in the exact center (of your enclosure), or it might be that the tweeter might need to be slightly skewed with woofer creeping a little more towards the center (of the enclosure). If you used two woofers, then the tweeter would undoubtibly be in the center (hence my initial recommendation). This concept isn't so easy to put into words, so let me know if I need to try again.

redtop: Once you get the enclosure built, I think this thread might interest you: http://forums.klipsch.com/idealbb/view.asp?topicID=9104&sessionID={F3BBE546-E922-4303-BE51-80F4BCF4E08E}

---------------- On 1/22/2003 8:39:58 PM HornEd wrote: PS: STL was giving you good advice... except that I would not add a woofer to an existing ported speaker because that would change the speakers volume dynamics. And, while STL is correct in pointing out that upwards of 75% of the total sound will be coming through your center channel... part of the benefit of the modified floorstander to center is to timbre match the center more exactly to the mains. Since you are using KG 3.5 of the R & L Mains... a KG 3.5 is the perfect match for the Center Main. You and your guests will be surprised and amazed... so don't forget to tell them about your Holiday Inn expertise! ---------------- Adding a second woofer, after more thought, isn't worth all the trouble. If would lead to changes in the crossover and require a much larger enclosure. Still, it is possible to add another identical 8" woofer and still keep the timbre matched. In fact, if done right it could reduce amount (Xmax wise) the woofer would need to move to create a given amount of SPL and would likely lead to cleaner midrange frequencies coming from the speaker -- which would be a particularly good thing for a center channel speaker (cleaner voices).

I would suggest buying another 8" woofer from Klipsch. Your center channel speaker typically "plays" more than even your front mains in 5.1 mode so adding another woofer wouldn't hurt (except you would have to re-work the crossover). I could help you with a design. I'm not an acoustic engineer either, but I am an electrical engineer who has a very good understanding of acoustics! What kind of TV do you have (picture tube, rear projection, etc.)? Shielding is easy (just order the bucking magnets from Klipsch) but may not be needed.

I thought I'd post an update in case anyone else is looking for the same stuff. Parts Express somewhat recently started carrying exactly what I was looking for: http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=260-010 I just bought four rolls, but haven't tried to apply it yet.

Please let us know how it works out. I had a KV-3 to go with my KG5.5s, but I always felt it couldn't quite keep up. So I am building my own center speaker (hey, I really am...the MDF was delivered today) using a tweeter, the K-85-K, that is exactly the same as the one in a KG5.5. That is how to get the best possible match.

well there are like 4 home audio posts in the promedia forums, should I regect them too?I didn't see any home audio posts in the ProMedia Technical Questions forum. Maybe you mean 4 out of the 2,500 total there are home audio related. If that is the case then that is not a problem. Now when the trend is moving to that HALF the posts here in the Home Audio Techincal Questions do not pertain to home audio then that is indeed a problem! BTW, I never said to reject anyone's question. Asking them to move it then aswering it in the correct forum was my suggestion. don't get all mad about something as little as this. geeze.Don't stick you head in the sand a deny there is a problem. All I am asking is that we all try to fix it. Is there really any harm in that? Like I have said before, posting ProMedia questions in the ProMedia forum (instead of here) would actually be MORE benefitial for ProMedia enthusiasts in the long run. After all, we have these different forum types for a reason.

Would it not be best if all ProMedia questions were answered in the one (correct) forum where other ProMedia users would likely be using Search function? If it is answered here, then someone searching for ProMedia help might never find it here.

Right now, 6 out of the first ten posts (ignoring this one) are about ProMedia...