Kool & Elfring Technical F.A.Q.

F.A.Q. (Frequently Asked Questions)

Q: Can I have another cabinet covering colour or grillcloth that is not in your online store?

Yes you can. Please contact us via specials@kool-elfring.com and we'll do our best.
(Please keep in mind that the deliverytime will be longer and that there might be price increase)

Q: Why don't you offer stereo cabinets?

It is our firm believe that a true stereo-sound can only be achieved by using two seperate speakers. (combined with a stereo effect) We don't like to do something we don't believe in. Besides that, we know from our own experience that stereo switches can be confusing, specially when you're on stage ..........
And last but not least, stereo-switches also tend to easily break ........

However, if you, for whatever reason, really really insist, we can make a dual input (but without switch!)
Please mail us at: specials@kool-elfring.com

Q: What's the difference between a dovetail woodjoint and a finger woodjoint??

The ‘DOVETAIL WOODJOINT’ is very strong because of the way the ‘tails’ and ‘pins’ are shaped. This makes it difficult to pull the joint apart and virtually impossible when glue is added.

The finger woodjoint is not bad and it is much easier, less time consuming and cheaper to make. Therefore the finger woodjoint is used by 99 percent of all speaker cabinet manufacturers. But at Kool & Elfring we want nothing but the best! That's why we do the dovetails to achieve much more rigid and stronger construction that will last. Please find pictures below (they speak for themselves!).

Dovetail Woodjoint

Finger Woodjoint

Q: Why don't you offer open back cabinets?

Well actually we do make them but we don't really promote them. We know it is a matter of taste but we hapen to like the sound of closed back's a lot better. If you want the back open, just put it in 'remarks' in the orderform at the checkout and we'll take care of it and ...... no extra charge.

Q: What is the difference between open and closed-back cabinets?

The closed-back type of cabinet has much more bass presence and a tighter feel. The sound is more directional, however, and can feel slower or less free and open. An open back gives a looser low end with less depth, and 'figure 8' directivity (sound field looks like an 8 when looked down on from above the cab). Sealed boxes give tight, deeper low end but are more directional, giving less spread of sound.

Q: Do you make speaker combinations e.g. V30's with G12T's?

Yes no problemo! Infact any speakercombination is possible but please be aware that some mixes are not such a good idea for various reasons. Anyway please contact us first. Send your request to specials@kool-elfring.com

Q: Do you also manufacture slanted cabinets?

Before answering this question I'd like to explain something about slanted cabinets.
The idea of a slanted cabinet is to improve monitoring, or in other words they are made that way so you should hear your own playing better. From our own experience we seriously doubt this is true. And if it where true, would really like to have a 100 watt tube-amp pointed directly to your precious ears?
In our quest for ultimate guitar sound we experimented a whole lot with all kinds of constructions. And of course part of our research was trying all kinds of other brands of both straight and slanted cabinets. One of our first conclusions was that straight cabinets had a far more pleasing sound compared to the slanted versions. The physics behind this phenomenon is that the projection of straight cabinets is more ‘even’ than slanted cab's.

Although we are very much aware of those R&R feelings 'the slanted look' evokes we prefer to choose sound over looks. So slanted cab's: No thanks....

Q: How do I break in my speakers?

Before breaking it in it's advisable to "warm up" the speaker gently for a few minutes with low-level playing or background hum.
Break in a speaker with a fat, clean tone: turn up the power amp volume to full, and control the level with the preamp gain. Use a level that will be quite loud, but not painful in a normal size room. Have the bass and mid up full, and the treble at least half. On your guitar, use the middle pick up position (if your guitar has more than one pick up) and play for 10-15 minutes using lots of open chords, and chunky percussive playing. This will get the cone moving, and should excite all the cone modes and get everything to settle in nicely.

The speaker will continue to mature over the years, but this will get it 95% of the way to tonal perfection in the shortest time.

Q: What's the difference between Alnico speakers and Ceramic speakers?

Alnico (AlNiCo) is a type of alloy (mixture of several metals) magnet which was used extensively in loudspeakers between 1930 and 1960. The price of cobalt (the 'Co' in AlNiCo) began to skyrocket, so the industry was forced to develop other types of magnets. Powdered ferrite magnets were developed using the ceramic process and subsequently became the standard magnet for loudspeakers.

The whole 'AlNiCo mojo' is about smooth compression at high average levels, such as what you would have running the amp flat out. AlNiCo (Aluminum-Nickel-Cobalt) is an alloy magnet and all alloy magnets are easier to demagnetize than comparable Ceramic (Strontium Ferrite) magnets. What this means is that as the voice coil starts moving in response to the input signal, it generates a magnetic field of its own that tries to demagnetize the magnet. As its effect lowers the available magnetic field of the AlNiCo magnet, the speaker becomes less efficient, the voice coil moves less, etc. The physics of it is that the small magnets near the surface of the magnet poles (which are called 'domains') begin to change state (or flip directions). The result is smooth compression, the same kind of operating curve compression that occurs in a tube amplifier.

The ceramic magnet, on the other hand, doesn't compress or demagnetize as easily, so the voice coil moves to its mechanical limit and won't go any farther. This is why some say ceramics sound a little edgey at high average levels as opposed to AlNiCo. However, by properly designing the entire magnetic circuit, ceramics can be made to behave quite well for desireable guitar amp tone and dynamics.

Some compare the two magnetic circuits to solid state amps versus tube amps, where the solid state amp gives it all its got then clips hard, while a tube amp compresses nice and smooth. The extension of this idea, then, is that with the AlNiCo, like the tube amp, you can seem to have a louder average volume since it gets compressed smoothly.

By the way, the compressing or demagnetization that occurs with the AlNiCo is not permanent. It springs right back to its design operating point.

Q: How does the size of the voice coil affect the sound?

The bigger the voice coil is, the more wire is used, the more pulling power you have to move the cone. With the proper match of components, you can get more sensitivity, wider frequency response, and more power handling ability.

Q: Can you also re-tolex my amp so it matches my cab?

No problem! Just contact us and we'll let you know what to do and what the cost are.

Q: Can you build a Kool & Elfring XLs cabinet with G12EVH custom build Celestion EVH speakers?

Well FYI, below you can read the original publication of Celestion of 12 July 2007.

Edward Van Halen's Custom Built Celestion "G12EVH" Speaker -12 July 2007-

Edward Van Halen and Fender have joined forces to create the EVH 5150IIITM amplifier. This incredible collaboration delivers ultimate Van Halen tone through 4 x 12 cabinets loaded with Celestion “G12 EVH” speakers. Throughout his career, EVH has sought out original Celestion 20-watt “Greenback” speakers to load into his recording and performing rigs. They have been part of his sound from day one. So, when designing the EVH 5150III it was to Celestion that EVH and Fender turned to, looking for that vintage Greenback sound. Celestion’s Heritage Series G12M speakers are a faithful reproduction of the original 1960s 20-watt Greenback and for EVH they provided the ideal solution. They delivered the tone he was chasing. But the story didn’t end there. For such a special project, Celestion wanted to give this speaker a look that was unmistakeably EVH–to turn it from a Heritage Series G12M into a “G12 EVH”. In the early 1970s, the trademark green rear can mounted to the back of the speaker had sometimes been produced in other colours. For the EVH model, we have reproduced the rear can in black, evoking the memory of the rare and much sought after Celestion “Blackback” speakers. Finally, to give this speaker the signature look it deserves, we added a specially designed label, featuring the Van Halen logo and unique EVH striped design. Edward Van Halen is a true guitar legend and has motivated countless aspiring players to pick up a guitar for the first time. Celestion are proud to be associated with EVH and with the EVH 5150III. For more details on the EVH 5150III head and cabinets, go to: www.evhgear.com

In other words: The Celestion "G12EVH" is technically a "Herritage Series G12M". The only difference is the special black rear can and the special designed EVH label ......

So the answer is: pick the XLs412G12MH cabinet (with the Herritage Series G12M's!)

*** Any references to Eddie Van Halen or Van Halen are for information purposes and do not imply any current association with or current endorsement of Kool & Elfring products by Eddie Van Halen or Van Halen. ***

Q: What is the consequence of pulling 2 tubes on amps with 4 power tubes?

First let's explain a bit about how your tube amp works. The transformer of your tube amp may be considered as a simple 'gearbox' for electrical voltage and current between tubes (motor) and loudspeaker (wheels). The ratio in this 'gearbox' is very important and it has a fixed value. When 'pulling' the tubes, the internal impedance of the tube amp is doubled. Because the ratio of the transformer is fixed, the impedance is also doubled on the loudspeaker-side of the transformer. For example: your 4 Ohm output connector of your amp changes into 8 Ohm and 8 Ohm changes into 16 Ohm etc.
So if you pull one tube from each pair, you reduce the power of the amp by 50%. However, due to the way we hear, this isn't much of a volume reduction. Because mistakes are easily made and because it does not really give you a bennefit, our advise would be to not do this. However, as long as you match your speaker impedance to your amp, it will not hurt your amp.

Q: What does impedance mean?

The impedance of the speaker is the mathematical combination of reactance and resistance at a particular frequency. Most speakers used in the music business are either 4, 8, or 16 Ohm speakers. You can check the impedance by to measuring the DC resistance of the voice coil with a Multimeter (put in to 'Ohm mode'). If it measures more than 4 ohms but less than 8 Ohms, you call it an 8 Ohm speaker. Same for the 8 to 16.

Q: Can I have the wheels (Swivel castors with 50mm tyres) on my XLs212 cabinet ?

Yes you can. When ordering please put your request in the 'remarks' section or send your order bij email. Extra charge for 4 wheels is EUR 17,50 incl. VAT (BTW).