Hello all,
maybe someone can help me. I am really desperate.
I am looking for a replacement for 2 x RCF Event 4000s.
Intended use from 100Hz and up (I have 2 x 18" subs plus active X-OVR plus XTI6002).
For the 3-ways I definitely need more "punch" than those old 15" 3 ways, but less "screaming" at high SPL levels. I could take a great deal of extra punch for sure but no more of that harsh screaming in mid-hi my current RCFs start to produce at around 115 - 120dB. I need WAY more headroom - and for some special setup reason that has to do with S/N I cannot use any mixer so I have to use the amps attenuators. This is only sensible with max 2 amps, so I can only spend one amp channel per speaker. So I d need an internal optimized crossover for the 3 - ways. I have Camco D Power 2, 2 x 650 at 8 Ohms, but I can ramp up the amp power too if needed. On 4 Ohms, that amp would anyway give like over 1100W per speaker.
Speakers can be 12" horn loaded 3 way or 15 " 3 way or the like. or equivalent high performance.
All the pro manufacturers push 12" - 2ways for their cost advantage, but I think that is not so clean in the midrange with the low freq transducer intermodulating the vocals right? So I d like to keep 3 way.
Total cost should not exceed EUR 5000 for the pair, that' about 6700 from the USD or about 5 ounces of the yellow metal that is real sound money and will ever be in contrast to those un-backet fiat paper currencies.
Don't care if this is the sales price or the sum of parts plus what the carpenter takes.
Anybody has any idea / plan or the like? don't think I am the only one having those troubles to get good speakers?
maybe someone can help me. I am really desperate.
I am looking for a replacement for 2 x RCF Event 4000s.
Intended use from 100Hz and up (I have 2 x 18" subs plus active X-OVR plus XTI6002).
For the 3-ways I definitely need more "punch" than those old 15" 3 ways, but less "screaming" at high SPL levels. I could take a great deal of extra punch for sure but no more of that harsh screaming in mid-hi my current RCFs start to produce at around 115 - 120dB. I need WAY more headroom - and for some special setup reason that has to do with S/N I cannot use any mixer so I have to use the amps attenuators. This is only sensible with max 2 amps, so I can only spend one amp channel per speaker. So I d need an internal optimized crossover for the 3 - ways. I have Camco D Power 2, 2 x 650 at 8 Ohms, but I can ramp up the amp power too if needed. On 4 Ohms, that amp would anyway give like over 1100W per speaker.
Speakers can be 12" horn loaded 3 way or 15 " 3 way or the like. or equivalent high performance.
All the pro manufacturers push 12" - 2ways for their cost advantage, but I think that is not so clean in the midrange with the low freq transducer intermodulating the vocals right? So I d like to keep 3 way.
Total cost should not exceed EUR 5000 for the pair, that' about 6700 from the USD or about 5 ounces of the yellow metal that is real sound money and will ever be in contrast to those un-backet fiat paper currencies.
Don't care if this is the sales price or the sum of parts plus what the carpenter takes.
Anybody has any idea / plan or the like? don't think I am the only one having those troubles to get good speakers?
for 5000 euro I would be looking at something from KV2Audio.
If I had the money (I don't) I would go with a pair of EX10 and either an EX1.2 or EX2.2 as a Sub (although you say you already have a Sub woofer) or maybe an ES system with a pair of ES1.0 etc....
But then I would be dreaming, although it may fit your budget....
If I had the money (I don't) I would go with a pair of EX10 and either an EX1.2 or EX2.2 as a Sub (although you say you already have a Sub woofer) or maybe an ES system with a pair of ES1.0 etc....
But then I would be dreaming, although it may fit your budget....
just puzzling over the rest of your post
there are many simple line amplifier/mixers etc. which would give you a master volume control without adding any (significant/noticeable) noise if you do not want to pad your signal down to suit the microphone input of a mixer.
I am afraid active cross over is almost always going to perform better than speakers with passive crossovers, and given your budget one of the many modern powered and processed boxes on the market would have to be obvious contenders (I use QSC K10es with a subwoofer and this set-up works very well for me).
Also I am wondering if the 'Harsh screaming" you mention could be distortion creeping in somewhere when you push the system hard.
Perhaps you could tell us more about your current rig so I can understand your application more?
So I take it you are coming directly out of, something and then going into your amplifier.
there are many simple line amplifier/mixers etc. which would give you a master volume control without adding any (significant/noticeable) noise if you do not want to pad your signal down to suit the microphone input of a mixer.
I am afraid active cross over is almost always going to perform better than speakers with passive crossovers, and given your budget one of the many modern powered and processed boxes on the market would have to be obvious contenders (I use QSC K10es with a subwoofer and this set-up works very well for me).
Also I am wondering if the 'Harsh screaming" you mention could be distortion creeping in somewhere when you push the system hard.
Perhaps you could tell us more about your current rig so I can understand your application more?
"So I take it you are coming directly out of, something and then going into your amplifier."
I think I ll come directly out of DSP that is always at nominal level since I dont want 2 use a mixer / vol cont. before the DSP s input. So I can use a cheap and still decent DSP like Behringer 2496 and still have good S/N if the signal AND the noise gets turned down by the amps attenuators at lower listening levels.
The XTI6002 for the subs has an additional DSP in the signal path which I do not really use other than for bridging but that is not causing any noise since its bass only, I am only concerned about that "hiss" from the tweeter.
the DSP has a parametric EQ in the input so I can correct several speaker response peaks / dips, but need to know exact parameters. Still I need to try out how many EQ points the DSP processor manages to real-time-calculate when simultaneously doing the XOVR / mono bass summing / delay adjustment thing in stereo....
The 5000 euro comes from my schedule that says I want to have evrything up n running in late spring of 2015, so still some month to save up one two or more salaries till that date...
I think I ll come directly out of DSP that is always at nominal level since I dont want 2 use a mixer / vol cont. before the DSP s input. So I can use a cheap and still decent DSP like Behringer 2496 and still have good S/N if the signal AND the noise gets turned down by the amps attenuators at lower listening levels.
The XTI6002 for the subs has an additional DSP in the signal path which I do not really use other than for bridging but that is not causing any noise since its bass only, I am only concerned about that "hiss" from the tweeter.
the DSP has a parametric EQ in the input so I can correct several speaker response peaks / dips, but need to know exact parameters. Still I need to try out how many EQ points the DSP processor manages to real-time-calculate when simultaneously doing the XOVR / mono bass summing / delay adjustment thing in stereo....
The 5000 euro comes from my schedule that says I want to have evrything up n running in late spring of 2015, so still some month to save up one two or more salaries till that date...
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If you went with something like the KV2 system, processing, crossover etc, is all built in and that system does go hard, and sounds very nice (as I said I wish I could afford one) the only reason for running external processing would be to retain your existing sub-woofer set up.
Although checking UK pricing KV2 may be slightly out of your range (depending on where you are - I am used to overseas pricing for this sort of gear to be half of Australian pricing, but in this case it may not be).
If you went with the (less expensive) QSC K series or slightly more upmarket QSC KW ( the KW153 would be in your price range, as would other similar systems on the market) Processing is built in, so no need for cross over etc just use the XTI cross over for your sub-woofer and throw the switch on the rear of the speaker to tell it you are running with an external Sub.
They also have other processing built in so you do not need to EQ for the speakers (although EQ to help with the room is always good) and they sound pretty damn good out of the box, generally better than most bar the best passive speakers, so nowadays it is difficult to recommend anything that is not powered and processed.
From another practical view point you can push them hard, if you go too hard the built in limiter takes care of things, and they look after themselves.
Then you need a volume control (or you have to run around the speakers) and the K series do have (wired) remote volume control capability allowing you to control all the speakers from a single potentiometer.
But if this is for a portable system, then that is something else to set up, so some other inline master control would be preferable/easier to set up (if you went down this path).
Of course getting gain structure correct is always worth doing (just because you can turn all the level controls up full, doesn't always mean that is a good idea*) and if you get the gain structure correct with any half decent kit you should not have any noise problems of course if your gain structure is not correct (this is not a fault of the amplifier etc) then yep, you will get lots of hiss and noise.
* a typical power amplifier can be driven to full power with somewhere around 1 to 1.5V input, a typical mixing desk will drive its output to somewhere around 10Vrms, so if you have your power amplifier set to full, then yes, you will get lots of unnecessary hiss and your mixer would not be working at its best either.
Typically your power amplifier volume control is best set to somewhere between -10 and -20dB. Powered speakers are similar and I typically run mine (QSC K10es) at around -10 or so.
But I am still not clear on what your signal source is and why it doesn't already have a level control?
Although checking UK pricing KV2 may be slightly out of your range (depending on where you are - I am used to overseas pricing for this sort of gear to be half of Australian pricing, but in this case it may not be).
If you went with the (less expensive) QSC K series or slightly more upmarket QSC KW ( the KW153 would be in your price range, as would other similar systems on the market) Processing is built in, so no need for cross over etc just use the XTI cross over for your sub-woofer and throw the switch on the rear of the speaker to tell it you are running with an external Sub.
They also have other processing built in so you do not need to EQ for the speakers (although EQ to help with the room is always good) and they sound pretty damn good out of the box, generally better than most bar the best passive speakers, so nowadays it is difficult to recommend anything that is not powered and processed.
From another practical view point you can push them hard, if you go too hard the built in limiter takes care of things, and they look after themselves.
Then you need a volume control (or you have to run around the speakers) and the K series do have (wired) remote volume control capability allowing you to control all the speakers from a single potentiometer.
But if this is for a portable system, then that is something else to set up, so some other inline master control would be preferable/easier to set up (if you went down this path).
Of course getting gain structure correct is always worth doing (just because you can turn all the level controls up full, doesn't always mean that is a good idea*) and if you get the gain structure correct with any half decent kit you should not have any noise problems of course if your gain structure is not correct (this is not a fault of the amplifier etc) then yep, you will get lots of hiss and noise.
* a typical power amplifier can be driven to full power with somewhere around 1 to 1.5V input, a typical mixing desk will drive its output to somewhere around 10Vrms, so if you have your power amplifier set to full, then yes, you will get lots of unnecessary hiss and your mixer would not be working at its best either.
Typically your power amplifier volume control is best set to somewhere between -10 and -20dB. Powered speakers are similar and I typically run mine (QSC K10es) at around -10 or so.
But I am still not clear on what your signal source is and why it doesn't already have a level control?
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"I am afraid active cross over is almost always going to perform better than speakers with passive crossovers, and given your budget one of the many modern powered and processed boxes on the market would have to be obvious contenders (I use QSC K10es with a subwoofer and this set-up works very well for me).
"
Honestly i ve been looking into actives also, but consider the passive solution superior in terms of noise / tweeter hiss).
Look here:
EV-ETX35P - no way - too much noise hiss... (btw: do they use active xovr plus 3 amps or do they cheat and use just the same 2000W module in all ETX models plus passive LCR XOVR? Who knows that?)
JBL PRX735 - no way - has no internal high-pass - so I would need to go through the rack mounted DSP AND through the active PRX input electronics..
Mackie HD1531: same issue - no highpass settings.
Only options in the active area still on the table are:
QSC KW153 (not sure about the noise - need to find out - but how? I could do some remote-gain using the QSC-5V gain pot voltage divider input, but does it turn lower the noise also if the remote-gain is set lower or is it just turning lower signal at the input leaving the hiss un-changed???)
Lambda Labs TX-3A (will maybe not fit into the budget, but has some high performance low noise ADC DSP section..)
Because of the volume control issue (I don't want to go behind each speaker to set volume), I need to use attenuators on amps - so I d need to go passively X-Overed speakers. Honestly I don't like the idea of mixer plus inputting attenuated low signals into an active speakers input that has ADC plus DSP, using effectively less bits of resolution on lower volume.
"
Honestly i ve been looking into actives also, but consider the passive solution superior in terms of noise / tweeter hiss).
Look here:
EV-ETX35P - no way - too much noise hiss... (btw: do they use active xovr plus 3 amps or do they cheat and use just the same 2000W module in all ETX models plus passive LCR XOVR? Who knows that?)
JBL PRX735 - no way - has no internal high-pass - so I would need to go through the rack mounted DSP AND through the active PRX input electronics..
Mackie HD1531: same issue - no highpass settings.
Only options in the active area still on the table are:
QSC KW153 (not sure about the noise - need to find out - but how? I could do some remote-gain using the QSC-5V gain pot voltage divider input, but does it turn lower the noise also if the remote-gain is set lower or is it just turning lower signal at the input leaving the hiss un-changed???)
Lambda Labs TX-3A (will maybe not fit into the budget, but has some high performance low noise ADC DSP section..)
Because of the volume control issue (I don't want to go behind each speaker to set volume), I need to use attenuators on amps - so I d need to go passively X-Overed speakers. Honestly I don't like the idea of mixer plus inputting attenuated low signals into an active speakers input that has ADC plus DSP, using effectively less bits of resolution on lower volume.
I think you will find the EV speakers use DSP based cross over and processing with (usually) two D class amplifiers, one driving the LF driver and another driving a passive crossover between the high and mid. they would use the same amplifier/DSP module in all the ETX speakers, but with different firmware for each.
I haven't used the EV speakers (but had heard some good reports) having mainly used the QSC and (occasionally) KV2. The QSC do have high pass and with no input are not too noisy - the remote volume control results in the level being changed on the DSP (so after the input circuitry) but I have to confess that I have not used the remote volume control.
I am curious about your noise concerns, as they do suggest a gain structure problem, but without knowing what your signal source, or application is I am still in the dark as to what the problem might be.
Usually in the scheme of things, the very small amount of noise from a line level ADC and DSP is not likely to be significant.
I mean powering up a K10 now, it is night time here, with very little background noise, and sure I can hear hiss from it a meter or so away, but only if I turn my heater off and it would not be likely to be noticed unless you were looking for it.
Add any background noise, or program material and you wouldn't hear it. In fact comparing it with an Australian monitor PA1200 amplifier, with gain on minimum and driving a B&C 8cx21 loaded foldback speaker, while sure the amplifier is slightly quieter, it is not significantly so, and the fans from the amplifier (particularly by the time it warms up) are louder than the hiss from the speaker (and of course you usually have the amplifier backstage somewhere). But if that level of noise bothers you then you probably aren't going to like any active box.
Either way I would suggest borrowing or hiring a QSC (or any other speaker that anyone else may suggest) before buying one anyway, if only to get a feel for how it sounds and performs. After all just because I like/am happy with a speaker doesn't always automatically mean you will be and after all my application/use may be quite different to yours.....
I haven't used the EV speakers (but had heard some good reports) having mainly used the QSC and (occasionally) KV2. The QSC do have high pass and with no input are not too noisy - the remote volume control results in the level being changed on the DSP (so after the input circuitry) but I have to confess that I have not used the remote volume control.
I am curious about your noise concerns, as they do suggest a gain structure problem, but without knowing what your signal source, or application is I am still in the dark as to what the problem might be.
Usually in the scheme of things, the very small amount of noise from a line level ADC and DSP is not likely to be significant.
I mean powering up a K10 now, it is night time here, with very little background noise, and sure I can hear hiss from it a meter or so away, but only if I turn my heater off and it would not be likely to be noticed unless you were looking for it.
Add any background noise, or program material and you wouldn't hear it. In fact comparing it with an Australian monitor PA1200 amplifier, with gain on minimum and driving a B&C 8cx21 loaded foldback speaker, while sure the amplifier is slightly quieter, it is not significantly so, and the fans from the amplifier (particularly by the time it warms up) are louder than the hiss from the speaker (and of course you usually have the amplifier backstage somewhere). But if that level of noise bothers you then you probably aren't going to like any active box.
Either way I would suggest borrowing or hiring a QSC (or any other speaker that anyone else may suggest) before buying one anyway, if only to get a feel for how it sounds and performs. After all just because I like/am happy with a speaker doesn't always automatically mean you will be and after all my application/use may be quite different to yours.....
"I am curious about your noise concerns, as they do suggest a gain structure problem, but without knowing what your signal source, or application is I am still in the dark as to what the problem might be."
There is no problem - just high expectations: Since it is a home discotheque, I want to be able to listen at "room levels" without hiss, even at "sleep" levels, but also would like to not rock the house but shake it's walls loose if I choose to do so. And I may often choose to do so. too often for my ears... (remember - no excessive screaming just chest pounding punch)
Hiss a meter ago is too much. The ETX-Electro-voice I can hear in a modestly quiet environment (shop), at around 80 cm - way too much ssshhhhh....
There is no problem - just high expectations: Since it is a home discotheque, I want to be able to listen at "room levels" without hiss, even at "sleep" levels, but also would like to not rock the house but shake it's walls loose if I choose to do so. And I may often choose to do so. too often for my ears... (remember - no excessive screaming just chest pounding punch)
Hiss a meter ago is too much. The ETX-Electro-voice I can hear in a modestly quiet environment (shop), at around 80 cm - way too much ssshhhhh....
Here is a hand written diagram of my ideas - hopefully you can read this.
Passive solution would use attenuators. Active would use mixer vol control.
Another option I am thinking of these days is: Go the passive solution but replace only the old beaten-up 15"s in both RCFs by a better new woofer (similar T/S plus much higher power rating). Maybe up the power amp a bit (like D-Power 3 or the like) and push the 15"s way harder through gentle EQ boost at 100 - 300Hz. That solution would be WAY below 5000 EUROS but depends on the lifetime of the old 8"s and the tweeters (do those speakers tend to wear out too over the years?). anyway those could be replaced later on too - would not be so expensive.
Passive solution would use attenuators. Active would use mixer vol control.
Another option I am thinking of these days is: Go the passive solution but replace only the old beaten-up 15"s in both RCFs by a better new woofer (similar T/S plus much higher power rating). Maybe up the power amp a bit (like D-Power 3 or the like) and push the 15"s way harder through gentle EQ boost at 100 - 300Hz. That solution would be WAY below 5000 EUROS but depends on the lifetime of the old 8"s and the tweeters (do those speakers tend to wear out too over the years?). anyway those could be replaced later on too - would not be so expensive.
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Fair enough, and understanding your application does actually explain a lot.
So you are effectively running a home stereo type set-up that can also be used as a Disco (or probably more accurately, a Disco that you wish to use as home stereo).
So while In a traditional PA/Sound reinforcement application, any minor noise levels these speakers have, would usually be well and truly buried in the venue/background noise, even just half a room full of people breathing, I can see your application is slightly more sensitive in this regard.
It is probably worth mentioning here, that many modern D class type amplifiers tend to be slightly noisy inherently, so if you are happy with your Camco I would not rush to replace it.
Compression drivers (the tweeters in most PA boxes) do start to distort when driven harder (although being horn loaded, in theory they should not NEED to be pushed as hard) and I wonder if this could be the cause of some of your concern about the sound of your current set-up.
Even if not being pushed too hard, the tighter pattern control of a horn loaded compression driver may make it unsuitable for a home stereo type application as at the very least you will probably find that your top end changes as you move your head (an effect common on "less expensive" fold-back wedges, which I personally find annoying, but which many other folk do not notice) .
Most "Punch" is usually considered to be 50-100Hz which would be from your Sub-woofer, (although some of it can be up to 150Hz or so), once you approach 200-300Hz this is usually described as warmth (or mud, if you have too much)
Looking at your diagram you have the two 18" Subs in series giving a 16 ohm load to the amplifier, while I note that the XTI6002 is rated down to 4 ohms in bridged mode. running the subs in parallel will effectively give you another 6dB on your bottom end.
Then think about your sub location, one of the biggest mistakes with Sub-woofers in PA usage is to run stereo Subs (that is one sub-woofer each side of the stage), at best this results in uneven bottom end across the room.
Ideally as a simple rule of thumb is locate both Subs together in one corner of a room (or at least tight into a wall) and see how that goes.
Of course this could just be a semantics thing, and what you call "punch" is what I call "warmth".
speakers don't usually wear out as such, however abuse and physical damage, or less commonly, deterioration over time (such as the infamous foam surrounds of the 70es and 80es) can cause some change.
While many faults are buried deep in a driver (such as coil damage or misalignment) others can be picked up by a visual examination.
One potential issue (in an older driver) which can cause odd distortion, is if the surround becomes detached from the frame gently poke the edge of the cone from behind and look for any lifting of the surround.
This is presuming that your boxes are faulty, rather than merely just not suitable for your application and offhand nothing springs immediately to mind to recommend in your case....
Which does not solve your immediate quandary, but may give you something to ponder.
If I get time over the weekend I will try the remote volume control option on my K10es and see how that affects the inherent background hiss (as with the EV modules the same amplifier module is used across the QSC range with different firmware loaded into each) in theory at least, that may work, but then that assumes the noise is on the front end rather than elsewhere after the DSP....
Thanks for your considerations.
Camco is great and has been chosen for S/N being really good, but they have more powerful ones too.
Running the subs in parallel would give 1. much less damping. 2. absolutely no benefit, since I cannot clip this amp even into 16 Ohms. It can cook my 2 x 18sound 18NLW9400 even in series. Currently I have an rms limiter at 58VRMS, e. g. 116VRMS for series bridge. the 18s could eat a little more, but I am not going to play with their actual limit and then be 5% above and -- smoke....
Subs are close to each other to gain max. efficiency through coupling.
Thanks for the effort to check out QSC remote gain - its just one potentiometer to be connected, I think.
If the EV ETX-35P really uses 2 way amplification plus passive mid/hi filter, I d consider that as a sound solution (like PRX735) , assuming they are able to implement this well. Still, the noise of ETX is too high. I want to be able to sleep in front of the speaker at night (as long as no one puts up some tunes ;-)
Camco is great and has been chosen for S/N being really good, but they have more powerful ones too.
Running the subs in parallel would give 1. much less damping. 2. absolutely no benefit, since I cannot clip this amp even into 16 Ohms. It can cook my 2 x 18sound 18NLW9400 even in series. Currently I have an rms limiter at 58VRMS, e. g. 116VRMS for series bridge. the 18s could eat a little more, but I am not going to play with their actual limit and then be 5% above and -- smoke....
Subs are close to each other to gain max. efficiency through coupling.
Thanks for the effort to check out QSC remote gain - its just one potentiometer to be connected, I think.
If the EV ETX-35P really uses 2 way amplification plus passive mid/hi filter, I d consider that as a sound solution (like PRX735) , assuming they are able to implement this well. Still, the noise of ETX is too high. I want to be able to sleep in front of the speaker at night (as long as no one puts up some tunes ;-)
a disco to double as home stereo - right.
"speakers don't usually wear out as such, however abuse and physical damage, or less commonly, deterioration over time (such as the infamous foam surrounds of the 70es and 80es) can cause some change.
While many faults are buried deep in a driver (such as coil damage or misalignment) others can be picked up by a visual examination.
One potential issue (in an older driver) which can cause odd distortion, is if the surround becomes detached from the frame gently poke the edge of the cone from behind and look for any lifting of the surround."
the RCFs are not dead, but approaching 20 years. foam surrounds still fairly good, but I am thinking of replacing them because: They will die anyway latest within the next 10 years AND I need more of the good P's
Punch
Power
Plenty of Headroom
but less of the bad S's:
screaming
shitty
sound
Maybe it is "warmth" what I am lacking ("mud"???, or is it just an overdose of ear-killing 2kHz - 10kHz screaming frequency area? I don't know. At medium listening levels the RCFs sound just good!! That again points to the concept of Headroom can only be replaced by ... guess what......more Headroom.
"speakers don't usually wear out as such, however abuse and physical damage, or less commonly, deterioration over time (such as the infamous foam surrounds of the 70es and 80es) can cause some change.
While many faults are buried deep in a driver (such as coil damage or misalignment) others can be picked up by a visual examination.
One potential issue (in an older driver) which can cause odd distortion, is if the surround becomes detached from the frame gently poke the edge of the cone from behind and look for any lifting of the surround."
the RCFs are not dead, but approaching 20 years. foam surrounds still fairly good, but I am thinking of replacing them because: They will die anyway latest within the next 10 years AND I need more of the good P's
Punch
Power
Plenty of Headroom
but less of the bad S's:
screaming
shitty
sound
Maybe it is "warmth" what I am lacking ("mud"???, or is it just an overdose of ear-killing 2kHz - 10kHz screaming frequency area? I don't know. At medium listening levels the RCFs sound just good!! That again points to the concept of Headroom can only be replaced by ... guess what......more Headroom.
From today's investigation (opening the speakers) I have found out the following:
The LF speaker of RCF Event 4000 is L15P530. It has about 93liter net volume to operate into plus 2 round ports, each 10cm in diameter and 8 cm long (effective length would be like 10 cm or so). Any RCF expert here to confirm that?
RCF states the tuning frequ. = 45Hz. Need to start the simulator to see if that fits.
Next step would be to find a possible speaker replacement. No electrolytics in the X-Over, only foil caps, resistors, a 24V light bulb to protect the tweeter and a big iron core choke, which I could replace by a higher current-capable self-built one....
The LF speaker of RCF Event 4000 is L15P530. It has about 93liter net volume to operate into plus 2 round ports, each 10cm in diameter and 8 cm long (effective length would be like 10 cm or so). Any RCF expert here to confirm that?
RCF states the tuning frequ. = 45Hz. Need to start the simulator to see if that fits.
Next step would be to find a possible speaker replacement. No electrolytics in the X-Over, only foil caps, resistors, a 24V light bulb to protect the tweeter and a big iron core choke, which I could replace by a higher current-capable self-built one....
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...So that shows it takes me over three weeks to get around to a simple test....
using the remote volume control on my QSC K10es significantly reduces the residual background hiss from the speakers,
At minimum level on the remote volume control, during daytime (so some background noise) but with doors closed I could not discern background hiss at arms length at least not clearly, I could just sense a change as I moved off axis but not enough to say I was clearly hearing hiss.
with an RCF L15P530 with a 93 litre cabinet and two ports 10cm dia 8cm deep WinISD gives me a tuning frequency of 67Hz and an expected frequency response of:
using the remote volume control on my QSC K10es significantly reduces the residual background hiss from the speakers,
At minimum level on the remote volume control, during daytime (so some background noise) but with doors closed I could not discern background hiss at arms length at least not clearly, I could just sense a change as I moved off axis but not enough to say I was clearly hearing hiss.
with an RCF L15P530 with a 93 litre cabinet and two ports 10cm dia 8cm deep WinISD gives me a tuning frequency of 67Hz and an expected frequency response of:
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thank you so much for your help. looks like qsc kw is some decent speaker. however, now it looks i ve decided to go the cheap way: continue using the rcfs, just swapping out all 3 transducers per speaker during winter time .it is less than usd 1000. the screaming i can improve by dcx input eq and with all transducers replaced i ll get like new sound. using the attenuators and always "full" signal like 4dbu within dcx2r96 really gives very low noise. the thing i am starting to get worried now is the sound of the amps fans as well as the noise of my disco light sphere turning... but thats another story....
the rcf 15 speaker plus the 93liters plus ports as described has about 47hz reso according to basscad what i use. the datasheet of rcf speaker shows impedance minimum at around 45hz. so you might have some parameter wrong. anyway i am not going to change much with thiele small just replace the same speaker by a new one or by a different one with similar thiele small paras. any suggestion of a good 15 inch speaker?
i set up the dcx at 110 hz linkwitz 4th order both lowpass and highpass pluss some input boost at 93hz for punch. not so bad any more if i pull some db around 2-10 khz.
reason for the lowercase letters is that i got myself a galaxy note pro 12.2 and the screen keyboard makes me not use the shift key. otherwise it is a great tablet.
the rcf 15 speaker plus the 93liters plus ports as described has about 47hz reso according to basscad what i use. the datasheet of rcf speaker shows impedance minimum at around 45hz. so you might have some parameter wrong. anyway i am not going to change much with thiele small just replace the same speaker by a new one or by a different one with similar thiele small paras. any suggestion of a good 15 inch speaker?
i set up the dcx at 110 hz linkwitz 4th order both lowpass and highpass pluss some input boost at 93hz for punch. not so bad any more if i pull some db around 2-10 khz.
reason for the lowercase letters is that i got myself a galaxy note pro 12.2 and the screen keyboard makes me not use the shift key. otherwise it is a great tablet.
so now i got into more troubles.
1.the xti6002 during startup will pass about .5secs of audio completely unattenuated and un-dsp'd before booting into the current setup which causes me to change the startup process to have the amp fully ON and booted into the dsp program running and attenuated before i can startup the mp3 player or the dcx coz otherwise i risk killing my 18s with unfiltered unattenuated maximum signal.
2. i ve spent bout 8 hours setting the right delay to match the xover phase between subs and rcfs. now i ve "good" phase between bout 75 hz and 175hz. i do this by placing a spl meter between subs and rcfs and using a sine generator find the delay that gives best cancellation then adding or cutting half a wave period for the setting -depend son what setting gives best overall result over the range of bout .7 - 1.5 x fxover.
to not in any case hurt this perfect setting, i cannot use the amp's dsp's internal subsynth to fatten the bass, since i then risk that the perfect crossover phase gets hurt by subsynth's harmonics. so i d have 2 buy dbx120a for use be4 the xovr that no phase imbalance can occur. the xti subsynth if enabled will place an additional lowpass into the dry signal chain as well. not good for the phase match. i raised that to crowns technical field engineering they said well thats life. i really would need that subsynth to only affect the sub 60 hz area otherwise i cannot use it.
1.the xti6002 during startup will pass about .5secs of audio completely unattenuated and un-dsp'd before booting into the current setup which causes me to change the startup process to have the amp fully ON and booted into the dsp program running and attenuated before i can startup the mp3 player or the dcx coz otherwise i risk killing my 18s with unfiltered unattenuated maximum signal.
2. i ve spent bout 8 hours setting the right delay to match the xover phase between subs and rcfs. now i ve "good" phase between bout 75 hz and 175hz. i do this by placing a spl meter between subs and rcfs and using a sine generator find the delay that gives best cancellation then adding or cutting half a wave period for the setting -depend son what setting gives best overall result over the range of bout .7 - 1.5 x fxover.
to not in any case hurt this perfect setting, i cannot use the amp's dsp's internal subsynth to fatten the bass, since i then risk that the perfect crossover phase gets hurt by subsynth's harmonics. so i d have 2 buy dbx120a for use be4 the xovr that no phase imbalance can occur. the xti subsynth if enabled will place an additional lowpass into the dry signal chain as well. not good for the phase match. i raised that to crowns technical field engineering they said well thats life. i really would need that subsynth to only affect the sub 60 hz area otherwise i cannot use it.
So turn on problem solved by 4 speaker switches between amp and speaker,
Disassembled the RCFs today and found the midrange 8" transducer is operating into about 4.3liters plus 2 ports, total port area ca. 18cm^3, port length ca 2 cm. I also disassembled the passive X over and will report the schematic here once analyzed (don't think the LCR circuit is a trade secret). Problem is that the midrange has just one marking that says "8L7" plus a sticker that says "4Ohm". Could not find any info on RCF 8L7 on the internet. At least I would like to find out the TS parameters in order to find a suitable replacement.
Is it risky in this arrangement (BR 15" LF section plus BR 8" mid section) to screw up the phase at the crossover (300Hz) if I use another transducer with different TS parameters? It looks btw, that the tuning of the mid range resonator is set to only 145Hz, one octave below the crossover. So its use is actually mostly cooling of the voice coil, not port resonance, right?
Disassembled the RCFs today and found the midrange 8" transducer is operating into about 4.3liters plus 2 ports, total port area ca. 18cm^3, port length ca 2 cm. I also disassembled the passive X over and will report the schematic here once analyzed (don't think the LCR circuit is a trade secret). Problem is that the midrange has just one marking that says "8L7" plus a sticker that says "4Ohm". Could not find any info on RCF 8L7 on the internet. At least I would like to find out the TS parameters in order to find a suitable replacement.
Is it risky in this arrangement (BR 15" LF section plus BR 8" mid section) to screw up the phase at the crossover (300Hz) if I use another transducer with different TS parameters? It looks btw, that the tuning of the mid range resonator is set to only 145Hz, one octave below the crossover. So its use is actually mostly cooling of the voice coil, not port resonance, right?
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