USparc Posted June 7, 2003 Share Posted June 7, 2003 It has been some time ago when I last posted, but now I have to post again. My latest project to take the next step with my RF-3's ended successfully. First I did the rewiring as you may remember. The flimsy wires where replaced with cat5 FTP cables. This improved things a little. But now it was time for a more agressive attack of the cabinet itself!! The picture in this post (rest will follow) shows the original RF-3 cabinet with just one brace accross the side pannels. This is definitly not enough!! (Not to speak of the dampening material) So I designed a kind of matrix (reloaded) structure. In the following post I will attach the RF3reloaded picture. So I'll be back ... in the next post Quote Link to comment Share on other sites More sharing options...
USparc Posted June 7, 2003 Author Share Posted June 7, 2003 Voila, here it is the RF3 reloaded.(drivers removed to see ...) The cabinet is almost totally death. I can hear the difference when knocking on the side panels. You also will notice that the horn has his own cabinet. The speakers weighs 5kg more to get just over 30kg (30.7 actually) So what is the result sound related. My expectation where more than fulfilled. The sound doesn't come from the cabinets anymore. The sound is really placed in the room which it makes very natural and more live like (even more then before ) But the most impressive is the lower part of the frequencies. I was really nailed to the ground with the impact of the bass they can generate. The cabinet must absorb some (a lot ) of lower frequencies. With the more than adequate bracing this is al gone. The drivers are very happy with there new housing and I can hear it to. This is the best tweak you can do for these speakers. Moreover: I recently auditioned the RF-7 and would expect some more braced cabinets with those large drivers. Sadly I must say that my RF-3 outperform the RF-7 no matter what. The sound just sticks on the RF-7 and indeed plenty bass is very boomy and doesnt come near to the impact my RF-3 can generate now. I took a look inside the RF-7 and was very disappointed with the little bracing they had. I could hear it also when knocking on the side panels. However I would like to know how RF-7 would sound with a good bracing structure. (Maybe someone to do the tweak???) So now you have an idea how (as I discovered also) important the cabinet is. I always thought it is important but it is very very very important!!!! Quote Link to comment Share on other sites More sharing options...
USparc Posted June 7, 2003 Author Share Posted June 7, 2003 Yes indeed. I couldn't resist doing also the RC3 as I noticed also some boxy sound when knocking on the cabinet of the RC3. It wasnt totally death either. The picture in this post shows the original. Next post will come with the RC3 reloaded. Quote Link to comment Share on other sites More sharing options...
USparc Posted June 7, 2003 Author Share Posted June 7, 2003 Ok, here it is. The result is very good but not as it was present with the RF-3's. But indeed the RC-3 is smaller, so the panel vibration is originally less. Quote Link to comment Share on other sites More sharing options...
jzoz01 Posted June 8, 2003 Share Posted June 8, 2003 Wow, looks awesome. I would like to do something like that myself. I must ask though, what exactly did you do? the pictures still leave a bit out. It looks like you just added eggshell foam in the RC3, but what about the RF3? Quote Link to comment Share on other sites More sharing options...
USparc Posted June 8, 2003 Author Share Posted June 8, 2003 Take a good look at the difference between RF3original and RF3reloaded pictures. Don't you see the bracing panels with the holes. There are 3 levels of horizontal bracing panels and 3 levels of vertical bracing panels. Also for the RC3. In the RC3original picture you can see the bracing panels next to the cabinet of the RC3. Quote Link to comment Share on other sites More sharing options...
Seidelin Posted June 9, 2003 Share Posted June 9, 2003 Re: Unleash the power of RF-3 and RC-3 Quote Link to comment Share on other sites More sharing options...
dblue Posted June 9, 2003 Share Posted June 9, 2003 USparc, I am very interested in doing this mod, and was wondering if you could post a detailed parts/supply/equipment used list, and some hints/tips/instrucions. This would be greatly appreciated. Thanks! Quote Link to comment Share on other sites More sharing options...
Frzninvt Posted June 9, 2003 Share Posted June 9, 2003 By adding all that stuff (bracing, foam, etc.) inside the cabinet you are altering the internal cabinet air volume which is NOT always a good thing. The drivers were designed to perform optimally in that particular enclosure and you have most certainly altered their performance and not necessarily for the better. It will affect the overall frequency response of the speaker robbing you of bass response. If it was necessary to do all that don't you think the engineers at Klipsch would have thought of it. You may be better off using better components in the crossover network and ease up on all the deadening (not death, you don't kill your speakers) a single thin layer of dynamat would have accomplished the same thing and taken up alot less cabinet volume. You really must be bored, hey whatever works for you I guess. I'd of left them alone and just enjoyed unless I was having some kind of problems. You know the old saying "If it ain't broke, don't fix it." Quote Link to comment Share on other sites More sharing options...
USparc Posted June 9, 2003 Author Share Posted June 9, 2003 Frzninvt, If klipsch done this with the RF-3 it wouldnt cost 600euro but over 2000euro each. Bracing a cabinet is not easy for commercial speakers. It takes time and can not be easily automated. It involves a lot of hand work to do this and that is very pricy. What if I tell you that RF-3s are not equally braced. The placement of the only brace (along the side panels) can vary in height quiet a lot. I have 4 RF-3s. 2 of them have consecutive serial numbers where the difference is minimal. But the other 2 . The bracing and foam has a minimal impact. Besides it is an open enclosure. The foam is only used for eliminating standing waves inside the cabinet and does not eat up air volume. Moreover the original foam is not that good. The RF-3II might be better. You see, klipsch tries to improve things but is limited because of the price tag of the RF-3. The cabinet of a speaker is the most important. It should be very solid so no vibration of the panels can occur otherwise the frequency response of the speaker is totally influenced. The cabinet must be DEATH --> kill the vibration please!!! I say: If it ain't broke, fix it anyway. 1 Quote Link to comment Share on other sites More sharing options...
dblue Posted June 9, 2003 Share Posted June 9, 2003 USparc, I don't know if you missed my post above, but anyway, I was wondering if you could post what you used to fashion these braces (both supplies and equipment), and some instructions on how you did the bracing. Thanks. Quote Link to comment Share on other sites More sharing options...
USparc Posted June 9, 2003 Author Share Posted June 9, 2003 No, I didn't. Mail should be arrived by now. Happy tweaking. Quote Link to comment Share on other sites More sharing options...
Jef Posted June 10, 2003 Share Posted June 10, 2003 Hello Usparc, yes I would also like to know how you did the tweaking, looks very good. I also noticed the vibrating panels of my RF3II's. Nice job. Jef Quote Link to comment Share on other sites More sharing options...
jzoz01 Posted June 11, 2003 Share Posted June 11, 2003 Could you send to to me as well? Quote Link to comment Share on other sites More sharing options...
USparc Posted June 12, 2003 Author Share Posted June 12, 2003 Ok, here is it for everyone. Material used : 1 MDF panel of 122cm x 61cm 12mm thickness. polyurethane construction glue. eggshell foam of 30mm thickness. There are 3 horizontal and 3 vertical panels. The horizontal panels are 18cm x 32.5 cm. The panels can be inserted in the cabinet via the woofer holes. They are as wide as the inner wideness of the cabinet. There are many holes drilled in to the panels to let the air pass through. The first two panels are placed just above and under the first woofer. The 3th panel is placed a little further then the bottom of the second woofer. These panels are connected with the vertical panels in different depths. The first vertical panel is at depth 12cm, the second at 20 and the third at 15 cm. Just see that the drivers can be placed back!! The length is defined by the placement of the horizontal panels. They are also 18cm wide. I will not give detailed figures because it depends from speaker to speaker. The only brace in the original RF-3 cabinet is differently placed among the RF-3s. Because of this you will have to change the placement of some panels. You have to build around the original brace panel. This can be very hard, but it is possible. The panels are glued step by step with polyurethane construction glue with the help of supporting braces. Don't forget to cut and place the eggshell foam in the different chambers on the inner side of the cabinet. Some places are hard to reach when some panels are glued. Those supporting braces are cut out of the same MDF panel. Be careful with polyurethane. It glues everything in matter of minutes and is very strong. I want to say that ones glued there is no step back. Happy tweaking Quote Link to comment Share on other sites More sharing options...
Jef Posted June 12, 2003 Share Posted June 12, 2003 Hello, I think Usparc might have found a genuine upgrade for the RF3. If you think about it, MDF is very efficient vibration reducing material and it will take a considerable amount of power to make them vibrate. If you can avoid these panels to vibrate that power will become available extra sound presure. In the same way the spikes will give better imaging, because they will reduce the tiny movements of the cabinet, reducing the vibration of the cabinet itself (also tiny movements) will increase the imaging even further. The reduction of the inner volume is more complex. The volume is calculated to work together with the port. reducing this volume will increase the lowest frequency. But it seems that Usparc added damping material as well which lowers the frequency again. Furthermore the inner volume is quiete large I don't know how much percentage reduction the extra boards stand for but this might well be relatively small. my 02 cents ... jef Quote Link to comment Share on other sites More sharing options...
m00n Posted June 13, 2003 Share Posted June 13, 2003 USpark, question for you. Why did you use cat5? Why not regualar high grade speaker wire? Say 12 gage monster or what ever? Now, I have never seen inside one of these speakers so for all I know that could have been what was in them in the first place. Quote Link to comment Share on other sites More sharing options...
sunnysal Posted June 13, 2003 Share Posted June 13, 2003 usparc, that looks like nice work. I just wanted to point out that I think you missed the point of an earlier post. when Frzninvt mentioned you have changed the internal cabinet volume as seen by the woofers he was right. bracing is great but three things have changed the cabinet volume, the material used to brace, the added foam inside and the split-isolation of the two sections. while you may like the results there is no doubt that you have changed the cabinet volume and thus affected the sound in that manner. the woofers were chosen for an optimum cabinet volume, this determined the size of the cabinets. If Klipsch had decided to brace and dampen as shown the woofers would have been changed to another spec to perfom best within that new cabinet. by not changing woofers to account for the reduced internal volume you are potentially running the woffers in a less than optimum manner. this could manifest in uneven frequency repsonse or amplitude variations. certainly will sound different. you like it better, that is great. but do not dismiss the comments made about this issue, they are basic speaker design issues. regards, tony Quote Link to comment Share on other sites More sharing options...
USparc Posted June 13, 2003 Author Share Posted June 13, 2003 M00n, I used cat5 ftp wire. Why?? It is cheap and has good qualities. I use braided cat 5 ftp(shielded utp) for connecting the speakers to the amp. You can see them in the background of the RF3reloaded.jpg . The braiding consists of 3 ftp cables. So in total I have individual 24(8x3) wires. The 12 colored ones are for + , the 12 white are for -. I have them biwired (In total 6 ftp cables to one speaker) It has almost the same construction as a kimber 4TC cable and is shielded. It also performs like a kimber cable at 1/40 of the price. Very dynamic and natural. I actually posted a while ago about my rewiring. So since I use it also outside the speaker it was obvious to use it also as internal wiring. Besides, why did klipsch upgrade the RF-3II with monster cable. The originals have just standard electrical wires (Rei Hsing AWM1007). Sunnysal, I dont dismiss the comments made by others. It is very obvious I changed the speaker. The internal volume is a little changed (even not to mention in such a large volume) , the dampening material, the wires, . I did this all for the better and it is. Klipsch designed the RF-3 in a certain budget. If you remove the drivers of an original RF-3 you will notice that what you find inside is far from perfect. The original foam is almost thrown inside, differs among RF-3s and is not fixed. It is even differently placed among the RF-3s. The wires of each driver are running like spaghetti. Some RF-3s are missing bracings on the sides where two panels are joined (my Rear RF-3s). Oeps different volume!!?? Jef already indicated that the volume is calculated to work together with the port. That port is heavily depended on the room response. I think that this one overrules the almost neglectable internal change in volume. Besides you can even try to alter the volume of your speaker by bringing a bag of sand in it to improve the room response. So dont think it is al perfect when a speaker is placed in a room. There is still a lot of tweaking to have a good room response. A speaker with a vibrating enclosure will do more harm to the room response than changing the internal volume a little. But Hey, I am happy that an already good sounding (probably due to the drivers) speaker in its price range can be lift up to another class with some good tweaks. I think that this can also not be dismissed. Anyway, Thanks for the replies so far. Quote Link to comment Share on other sites More sharing options...
Dflip Posted June 13, 2003 Share Posted June 13, 2003 It looks like a solidly put together box. The idea of strengthening the cabinets is a good one. Even the Cornwalls have a suggestion to put a piece of hardwood across the front baffle below the squawker to tighten up the cabinet. I believe you have changed the internal volume and therefore the Q factor. The horizontal bracing and the thicker foam will reduce the internal volume of the speaker. In all likelihood you may be hearing more bass, but you have moved the speaker to more of a home theatre subwoofer style, higher Q value. If this is what you are using it for, then great. If the intent is to have a speaker to use in a 2 channel setup, then this may not be a good thing. It tends to slow down the tightness of the bass, bad for music, good for HT. Just pointing out some of the pluses and minuses for those thinking about performing the same changes. Quote Link to comment Share on other sites More sharing options...
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