Audio Performance SK-F project

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   At the moment I have two SK-F cabinets with have been modified throughout the years. Both differ in loading and the current filters are not identical.
Cab 1:
12" --> L'acoustics HP BC122 (looks a lot like the 12TBX100) 
8"   --> No idea atm, no brand on it (needs a new dustcap)
1"   --> BMS 4548-16 (OEM)

Cab 2":
12" --> RCF L12P110K (is covered in dust and remains of the old damping foam?)
8"   --> same as cab 1 but condition is fine
1"   --> BMS 4548Plus-8 (OEM)

Current crossover frequencies are 600 Hz and 2000 Hz.
The cab has a filter between the 8" mid and 1" HF driver, the original filter is build for 16 Ohm nominal drivers. If the LA driver is a bit like the 12TBX100 the difference with the RCF is pretty big specifications wise. One BMS HF is 8 Ohm. 

First thing done, clean the inside of both cabs:

Current to do list:
-Check filters completely and draw up schematic
-Repair 8" driver and find out if it is the original one (or find spec sheet)
-Try o clean the RCF 12" although it looks almost impossile, it's a really sticky substance.
-Find two identical 12" drivers for low/mid section (I was thinking about something like the B&C 12MH32).
-Find two replacements for the BMS HF's

To be clear, the projects objective is not to make an amazing sounding cab, the recources and time aren't just there atm.

Edited by smitske96 - 07 November 2019 at 8:31pm

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smitske96 Members Profile Send Private Message Find Members Posts Add to Buddy List Young Croc Joined: 16 February 2016 Location: The Netherlands Status: Online Points: 1092	Post Options Post Reply Quote smitske96 Report Post Thanks(0) Quote Reply Topic: Audio Performance SK-F project Posted: 07 November 2019 at 8:21pm
	At the moment I have two SK-F cabinets with have been modified throughout the years. Both differ in loading and the current filters are not identical. Cab 1: 12" --> L'acoustics HP BC122 (looks a lot like the 12TBX100) 8" --> No idea atm, no brand on it (needs a new dustcap) 1" --> BMS 4548-16 (OEM) Cab 2": 12" --> RCF L12P110K (is covered in dust and remains of the old damping foam?) 8" --> same as cab 1 but condition is fine 1" --> BMS 4548Plus-8 (OEM) Current crossover frequencies are 600 Hz and 2000 Hz. The cab has a filter between the 8" mid and 1" HF driver, the original filter is build for 16 Ohm nominal drivers. If the LA driver is a bit like the 12TBX100 the difference with the RCF is pretty big specifications wise. One BMS HF is 8 Ohm. First thing done, clean the inside of both cabs: Current to do list: -Check filters completely and draw up schematic -Repair 8" driver and find out if it is the original one (or find spec sheet) -Try o clean the RCF 12" although it looks almost impossile, it's a really sticky substance. -Find two identical 12" drivers for low/mid section (I was thinking about something like the B&C 12MH32). -Find two replacements for the BMS HF's To be clear, the projects objective is not to make an amazing sounding cab, the recources and time aren't just there atm. Edited by smitske96 - 07 November 2019 at 8:31pm

smitske96 Members Profile Send Private Message Find Members Posts Add to Buddy List Young Croc Joined: 16 February 2016 Location: The Netherlands Status: Online Points: 1092	Post Options Post Reply Quote smitske96 Report Post Thanks(0) Quote Reply Posted: 11 November 2019 at 7:00pm
	New foam on the inside, and some minor woodwork has been done. Both filters have been checked and the components are ok. The only thing I have to do is measure the inductance of each inductor. New dustcap is ordered and the RCF is drying up a bit. It is still a bit wet and really sticky.

AM55 Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 16 August 2007 Location: Matlock Status: Offline Points: 1728	Post Options Post Reply Quote AM55 Report Post Thanks(0) Quote Reply Posted: 11 November 2019 at 11:55pm
	They look like interesting cabs. How different did they sound?

smitske96 Members Profile Send Private Message Find Members Posts Add to Buddy List Young Croc Joined: 16 February 2016 Location: The Netherlands Status: Online Points: 1092	Post Options Post Reply Quote smitske96 Report Post Thanks(0) Quote Reply Posted: 12 November 2019 at 10:00am
	One didn't have any mid/high, once I inspected the filters I saw that there were two faulty solderjoints. Low/mid was different soundwise, one had more pressence in the lower part of the spectrum (the one with the LA driver).

smitske96 Members Profile Send Private Message Find Members Posts Add to Buddy List Young Croc Joined: 16 February 2016 Location: The Netherlands Status: Online Points: 1092	Post Options Post Reply Quote smitske96 Report Post Thanks(0) Quote Reply Posted: 13 November 2019 at 11:35am
	Does anyone have tips about cleaning the RCF's cone? It is to that sticky anymore, but I doubt that I can get it off without the use of any fluids.

smitske96 Members Profile Send Private Message Find Members Posts Add to Buddy List Young Croc Joined: 16 February 2016 Location: The Netherlands Status: Online Points: 1092	Post Options Post Reply Quote smitske96 Report Post Thanks(0) Quote Reply Posted: 13 November 2019 at 2:41pm
	So after even being careful it's pretty clear that the cone is not savable. It already has two major tears close to the surround, and it probably more will come when being used. Reconing is also not high on my list because of the work and I still need to buy another one which would set me back more then find two capable replacements. For now I have: B&C 12MH32 Oberton 12B450 Lavoce WAN123.00 Edited by smitske96 - 13 November 2019 at 2:42pm

Peter Jan Members Profile Send Private Message Find Members Posts Add to Buddy List Young Croc Joined: 16 December 2008 Location: Belgium Status: Offline Points: 1019	Post Options Post Reply Quote Peter Jan Report Post Thanks(0) Quote Reply Posted: 13 November 2019 at 5:43pm
	I'm almost sure I still have some "NOS" HP BC122 from back in the day when I had KUDO cabinets in use. Could that be an option to replace the RCF ? Have to look for it and not 100% sure I still have them, but if they are, they can go for a price in the whereabouts of what an RCF recone would cost.

smitske96 Members Profile Send Private Message Find Members Posts Add to Buddy List Young Croc Joined: 16 February 2016 Location: The Netherlands Status: Online Points: 1092	Post Options Post Reply Quote smitske96 Report Post Thanks(0) Quote Reply Posted: 13 November 2019 at 5:59pm
	That would be an option, only not sure atm if such a driver would suit the cab. The 12" section should cover +-100Hz till 600Hz, large Xmax isn't necessar (it looks a lot like the 12TBX). Maybe tomorrow I have some time to do some testing with the driver.

Peter Jan Members Profile Send Private Message Find Members Posts Add to Buddy List Young Croc Joined: 16 December 2008 Location: Belgium Status: Offline Points: 1019	Post Options Post Reply Quote Peter Jan Report Post Thanks(0) Quote Reply Posted: 13 November 2019 at 6:56pm
	It looks like a TBX, but the BC122 has more efficiency, low(isch) Q, more suited to hornloading or in high tuned BR (low)mid duty. I'll have a look after them BC122 tomorrow...

smitske96 Members Profile Send Private Message Find Members Posts Add to Buddy List Young Croc Joined: 16 February 2016 Location: The Netherlands Status: Online Points: 1092	Post Options Post Reply Quote smitske96 Report Post Thanks(0) Quote Reply Posted: 13 November 2019 at 7:57pm
	If that's the case they would indeed be a good option. If you have the time, let me know. Thanks for the offer!

smitske96 Members Profile Send Private Message Find Members Posts Add to Buddy List Young Croc Joined: 16 February 2016 Location: The Netherlands Status: Online Points: 1092	Post Options Post Reply Quote smitske96 Report Post Thanks(0) Quote Reply Posted: 13 November 2019 at 10:55pm
	Some pics of the 8" driver that yet has to be identified. Pressed chassis, further only a serialnumber on the driver: CAMP . . 628601300052679

cravings Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 30 January 2007 Location: Ireland Status: Offline Points: 7442	Post Options Post Reply Quote cravings Report Post Thanks(0) Quote Reply Posted: 14 November 2019 at 1:23am
	i would totally have a go at that rcf with watered down pvc and some bits of jay cloth.. and the 8", could it be an old Ciare?