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Next Gen to Replace RF-7 II ?


norcuron
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Hi,

I was wondering if anyone has heard what may replace the RF-7 version II and when? They have been out a few years now and I would think something new is around the corner. I love my RF-7 First Generation but still like to think about the future. Thanks for info.

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well I base that upon making the loudspeaker better. You have already seen the crossover poing reduced fron the RF7 to the RF7 ll and if you want to keep the woffers the same sizr then a larger horn is the only logical combination to making a lower crossover point work.. Considering that they have already built and released what I am describing (past product) I think it is a reasonable assumption. It's what I plan to do. The speaker don't have to be larger if they don't want them to be. Best regards Moray James.

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Just throwing this out there: a good room correction program would go a long way in keeping a similar sound between the different generations of speakers. IMHO, that is a good reason not to skimp on the avr or pre-pro when spending so much on the speakers. My RF 7's have no harshness except the one time I ran them without the room correction at a very high volume.Setting up the speakers with a meter is just not the same as using room correction.

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Moray are you saying larger horn and lower crossover equals better sound? Maybe that's why the new jtr's I heard I liked so much? They have a huge very high end compression driver and I'm pretty sure I remember reading it was crossed at 700hz

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Well Yes and I do understand there is a big design group who believe differently about that. But if you simply asume that the fifteen inch woofer matches the 90 degree horns dispersion at 1500 Hz and say thats where I will place the crossover point (and this is a very common method) you are right in that both thre woofer and the horn are exibiting 90 degerr dispersion at thea 1500 Hz crossover point but at the same time as far as I am concerned you are doing this the wrong way. This is why you see the big boys with at minimum of a 4-way or 5-way horn rigs. The woofer in the above situation has matched the dispersion of the horn but it has done that by having developed multiple sources of those upper frequiencies from all over the surfce of the woofer in other words the woofer is in breeak up mode. The woofer is long past pistonic behaviour. That is exactly why I utilize an acoustic (F-11 felt) filter over my 12" woofer in my H3 to catch as much of that near crossover and make most of what you hear at crossover be what the mid horn is radiating I want the mid horn to be the primary source.So yeas the break up dispersion off the woofer and let the horn which is crossed to do the main job. In the originally dwscribes situation the woofer is providing you with lots of output but I simply don't like the results of what has to be happening to do that. I like to see drivers staying in the pistonic range of operation. Not suggesting this is the ultimate answer simply the one I am looking to and which seems to be working. Best regards Moray James.

PS: have tried to tidy this up some hope this helps. The original arrangement discussed is a great way to contrive maximum efficiency and output but it screws up a lot of important detail asa far as I am concerned and to me is not a reasonable option thoug as I sair theis method has oprevailed in the industry for a long time.

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I think what MJ is hinting to is that horns increase the efficiency of the speaker. Less cone movement, less distortion. Lowering the xo in the RF 7II compared to the RF 7 and the LF dirver works a little easier. A 3 or 4 way horn design delegates the work load to the different drives which handle a narrower frequency range more effectively. I think[^o)].

The lower a tweeter is xo, the more it is stressed at high power and the transient peaks may suffer. This is a desing issues and compromises have to be made. I think this is why the 3 way Heritage speakers xo the tweeter above 3000 Hz. This may explain why the 7's use the 1.75 in. tweeter. I think[*-)]

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That is essentially i. Once you pass the frequency point where a cone driver stops behaving pistonically its radiation pttern becomes a comples ever changing with frequency mess. which you dont wantto listen to. I am sure most off you have looked at computer generated break up mode of cones showing all the variou assortment of bizar nodal point and how the pattern shifts with frequency. Well all those multiple nodes are in fact multiple output points (of the same frequency) or sources over the surface of the cone and they then generate interference with one another that makes for wird polar response with hot spot lobes and nulls in both the horizontal and the vertical plane. this behaviour begins as soon as you ask a driver to reproduce frequency wavelengths which are shorter in length than the diametre of your driver. So yes you got your dispersion of the woofer and the horn to match up at some frequency but it is one of those becareful what you wished for times because its is way worse that you ever thought it would be. The multiple source points across a cone are what destroy your spatial cohearency. Best regards Moray James.

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its my brain, I am on some nasty pain killers right now combine that with little to no deep sleep and I am having a hard time. Sorry doing my best. Best regards Moray James.

[Y] It's all good. I enjoy reading your posts. Hope you get to feeling better soon.

Carl

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