an isolation isobaric

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   Hi guys. Ive recently picked up a pair of fane classic KC18-300C. 
I know these are nothing special, but like many others at the moment, I have a lot of spare time on my hands (and fortunately some spare wood    )

Ideally I would like to turn these into something that can be used at home and for small partys post lockdown, but due to the low power handling of the driver I was considering some form of isobaric loading, a 6th order bandpass, or a combination of the two (and certainly open to other suggestions!) 

I don't have much experience with hornresp, but I'm willing to take the plunge and put the hours in if anyone thinks it will wield a decent enough result.

Is this too much effort for what I have here? should I just consider a simple reflex design?  

Thought I might as well check before I made too much sawdust!

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hectorberman Members Profile Send Private Message Find Members Posts Add to Buddy List Registered User Joined: 25 May 2017 Status: Offline Points: 78	Post Options Post Reply Quote hectorberman Report Post Thanks(0) Quote Reply Topic: an isolation isobaric Posted: 10 May 2020 at 11:31pm
	Hi guys. Ive recently picked up a pair of fane classic KC18-300C. I know these are nothing special, but like many others at the moment, I have a lot of spare time on my hands (and fortunately some spare wood ) Ideally I would like to turn these into something that can be used at home and for small partys post lockdown, but due to the low power handling of the driver I was considering some form of isobaric loading, a 6th order bandpass, or a combination of the two (and certainly open to other suggestions!) I don't have much experience with hornresp, but I'm willing to take the plunge and put the hours in if anyone thinks it will wield a decent enough result. Is this too much effort for what I have here? should I just consider a simple reflex design? Thought I might as well check before I made too much sawdust!

Chris Grimshaw Members Profile Send Private Message Find Members Posts Add to Buddy List Registered User Joined: 10 September 2018 Location: Sheffield Status: Offline Points: 281	Post Options Post Reply Quote Chris Grimshaw Report Post Thanks(0) Quote Reply Posted: 11 May 2020 at 10:04am
	Isobaric is a way of using twice the number of drivers to reduce the cabinet size by about 40%. In theory, it's 50%, but you've gotta put the extra driver somewhere. IMO, it's best to avoid bandpass designs with potentially fragile drivers. The bandpass literally means you don't hear the driver distorting (much), so you think you can push them further. Then, suddenly, no more sound. I'd probably go ported, or maybe some kind of horn if you're feeling inventive. Chris
	Quality sound from Sheffield www.grimshawaudio.com

hectorberman Members Profile Send Private Message Find Members Posts Add to Buddy List Registered User Joined: 25 May 2017 Status: Offline Points: 78	Post Options Post Reply Quote hectorberman Report Post Thanks(0) Quote Reply Posted: 11 May 2020 at 2:35pm
	ok, thanks for your input! In that case I think It'll be a lot easier for me to model a g-sub type cabinet. By horn do you mean a proper front loaded horn? or do you think decent results could be achieved with a band pass horn design such as the es18 or possibly even a cubo18?

studio45 Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 16 October 2007 Location: United Kingdom Status: Offline Points: 3864	Post Options Post Reply Quote studio45 Report Post Thanks(0) Quote Reply Posted: 11 May 2020 at 3:05pm
	Just modelled it quickly in ES-18BPH - not too bad; good for about 122dB max 50-200Hz. Does have some problems with Xmax around 47Hz so a steep 45Hz highpass is needed, and- 6dB PEQ cut at about 150Hz. Also done a quick sim of a typical large ported box such as this kind of driver would commonly have gone into, 170l tuned to ~35Hz. Not as good in that - missing about 6dB output compared to the BPH and won't go as low either. With same highpass as BPH. Neither box really wants more than 100 watts into it though, to avoid going over Xmax. Not sure how much leeway these old units would have before you're hitting the backplate.
	Studio45 - Repairs & Building Commotion Soundsystem -Mobile PA

hectorberman Members Profile Send Private Message Find Members Posts Add to Buddy List Registered User Joined: 25 May 2017 Status: Offline Points: 78	Post Options Post Reply Quote hectorberman Report Post Thanks(0) Quote Reply Posted: 11 May 2020 at 4:11pm
	Well thats changed my plans once again! I wont be able to start building for atleast another week, so i think ill check out how it sims in the cubo. Does anybody have any tips for modeling a cubo in hornresp? Or even the input data? Im not super confident with the software yet and have only used it for ported designs. Thanks for the help too guys, it was only last night i posted this and ive already had some great information