I have an old Kustom 4x12. It's ported, made of MDF (?), and devoid of any helpful markings to tell me what model it is. From what I've gathered it's from the mid-70s. and is either a Lead III or Lead IV. It looks like this:
The speakers in it are unlabeled. I've read that these cabs came from the factory with either Eminence or SRO speakers, but its such an old cab that they could very well have been swapped at some point. The magnets of the speakers (which are round, not square) in my cab are stamped:
513-105782
8-16 ohms
29563
8858014
Do any of those numbers mean anything to you folks? I'd love some more info on what these mystery speakers are if anybody can help! Also, if anybody has any idea what model in particular this cab is, or how to tell the difference between a Lead III and IV I'd appreciate it. Thanks!
pleat Messages: 1452 Registered: June 2004 Location: Belding, Mi
Senior Member
The number on the speakers don't match anything I have on file. The Lead lll cab is 28"x28"x15 1/2" deep. will have one speaker jack. Original weight is 108lbs. Should have 4 or 6 oval vent holes in the back of the cab.
The Lead lV cab is 34" tall x 31" wide, and 15 1/2" deep. Weight is 112lbs. The cab should have two speaker output jacks with each pair of speakers connecting to the two amps inside the Lead lV head.
After 30+ years, it's hard to say what the speakers are or how the cabinet is wired. Photos of the actual cab front back and inside will shed more light on what you have.
pleat
Thanks for the quick reply! The measurements, single jack, and 6 ports all seem to match your description of the Lead III so thanks for that clarification! I'll snap some photos of the inside of the cab ASAP, but from being inside it I know that the speakers measure 16 ohms and are wired in parallel. Also, its visible from the front of the cab that they have the vented voice coil dust caps like the original speakers pictured in the photo I posted.
stevem Messages: 4733 Registered: June 2004 Location: NY
Senior Member
When viewing your cabinet from the front as in the photo you posted, do the speakers each that aluminum center voice coil cover with the black hole in the center?
If thats the case then they would be original to the cabinet I would say, the only strange thing is I can not out of all the numbers from your drivers that you listed match a manufactuer code and thats what`s strange!
In the era that your amp was made Kustom used CTS or Eminence made drivers and they would have number string starting with 137 and a space, or 67 and a space, for example 137 7545 which would be a CTS made driver from the 45th week of 1975.
As promised, here are some pictures, including a photo of the front where those conspicuous center voice coil covers are visible. Thanks for all the help so far folks!
It is a 2, you're right! Not sure why I was focusing my attention on the speaker with the most smudged out stamp, but the code is in fact 2858014. Can anyone make any sense of THAT code? Made in the 14th week of 1980 or something like that?
Other thoughts on the cab/speakers now that you've got me going: LOUD! I just A/B'd this cab with my G12T-75 Ampeg cab (Marshall 1960 clone - plywood construction) and it definitely has the edge on volume (though I would have assumed these speakers are far less sensitive than the G12T-75). The bass is also bigger coming out of this cab, particularly on the lower strings, but not quite as tight as the G12T-75s.
Kochens Messages: 80 Registered: April 2009 Location: Denmark
Member
The lll-lV Lead cabs where not made for high gain amps. I have a` 4x12 ported cab and I love it(copy of a lV lead) with 2 celestion vintage 30 and 2 G12H and the sound are:+++++++++++GREAT for ROCK.
pleat Messages: 1452 Registered: June 2004 Location: Belding, Mi
Senior Member
Keep in mind that the Kustom cab is a 4 ohm cabinet. Not sure what the impedance of the other cabinet is, so if the other cab is an 8 ohm cab, the kustom will sound louder.
One thing I'd check is make sure all the nuts are tight that hold the speakers in, also maybe add some insullation. Kustom was trying to cut costs, which is one reason the MDF construction rather than full plywood as the earlier cabs were built.
pleat
I've never insulated a cab - will doing so tighten up the sound? Also, will it lower the volume? Because I actually like how much air this thing moves so that may be a concern. Also, the Ampeg cab I compared this one to is 4 ohms as well.
stevem Messages: 4733 Registered: June 2004 Location: NY
Senior Member
What amp head are you pumping thru the cabinet?
If its a head with a tube output stage they always sound best when running them at their highest Impeadance as only then are you using the full secondary winding of the Output transformer.
On a multi taped output transformer for example the 16 ohm tap is the full winding, the 8 ohm tap uses 1/3 less of the winding and the 4 ohm tap uses only one half the winding.
Its kind of the same thing as if you put wide tires on your car for better handling, but you pumped them up with so much air that only half the tires tread width was in contact with the road.
Also if those Kustom/Rola speakers are well used then the surround and spider parts of the speaker may be allowing the cone to move too freely and be slow to return to its static postion. This will make for overly powerfull lows and what you precive as shadowed highs.
A way to test this is to plug a cable into the cabinet and hold a new 9 volt batter across the plug, in doing this you should jsut be able to see the speaker cones move.
If the cone travel seen aprocess 1/4" they are well played and need reconing.
Kustom_Bart Messages: 601 Registered: October 2010 Location: Greenville, MichiGUN
Senior Member
What Steve is saying is if the surrounds are beaten up, it is like bad shocks on a car and you would at least need new surrounds installed, but for the price, you are better off to have them re-coned and then you know that they are all good for a very long time.
I'm running a Peavey VTX Classic combo through the cab. I'm using the combo's speakers and have the Kustom running from the external speaker jack. The amp is 4 ohms with the internal speakers and switches to a 2 ohm tap with a plug in the external speaker jack, so altogether I'm running the 4 ohm internal and 4 ohm Kustom together at 2 ohms.
I tried the battery trick -cool test, but I don't think the cones were moving particularly far. I also tried a bit of insulation in the cab. It did tighten the bass, but also flattened out the sound a little. I will keep experimenting with this thing. Thanks for all the help!