Fastrac K mid-horn>>into Khorns - What is the improvement?

AudioJag

Active Member
I'm considering making the upgrade to the Fastrac K horns for my '79 Klipschorns. I really would appreciate the help of forum members, who have already installed them, to give their impressions of what improvements that they found with the upgrade so that I can make an informed decision.

Since I used to sell audio equipment in the 60s and 70s, I'm very aware of the audio "law of diminishing return" for your dollars. So the upgrade to the Fastrac Ks are about $800 for the complete pair. Not too bad, but no reason to be frivolous.

I will be installing the ALKeng CSW crossover. The tweeter K77 round magnet will remain (this can be replaced at a later date if needed).

Thanks for your help in advance.
 
With these aftermarket horns, I don't know who makes what....but, I'd definitely consider a 2" horn if you can.
 
With these aftermarket horns, I don't know who makes what....but, I'd definitely consider a 2" horn if you can.

Thanks Coytee.... your info and help is appreciated. I would be stretching my budget a bit too far to contemplate the 2" change. I am very conscious of the "diminishing return" issue. My guess is (and hoping is) that the CSW crossover will show me enough of an improvement, that I can say wow... maybe the Fastrac K horn would be worth the bucks. I'll install the CSWs when I get them, and test it out on one and see what we get.
 
The Volti Horn is set up well for the K horn using the entire area and still having room for the tweeter. This is the biggest horn you can put in the factory top hat. You can also run the stock K55 or a 2 inch driver with them. The kit is very well thought out and is the best sounding mid I have heard short of the K402.

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I would hit the gothover Dave 2" horns if possible. I ran 811s, 511s, alk horns, and have heard the 2" large throat horns. Dave's are the best for the way I listen.
 
I would be stretching my budget a bit too far to contemplate the 2" change. I am very conscious of the "diminishing return" issue.

Let me reword it a bit.

My understanding from reading posts made by others who know more than me (some by EE's, some by Roy)...

A 2" horn will have about 1/4 the distortion that a 1" horn has because the area of the 2" is 4 times larger than the throat of the 1".

I'll let others debate if a 75% reduction in distortion is an issue of diminishing returns. Having made that change, I can vouch that for me it was a substantial difference.

(note that I've not said anything about costs because I know the horns probably cost more and the drivers cost more)
 
A 2" horn will allways be better, 4 times the radiating area,,, SMITH HORNS have better horizontal coverage,,,(JBL 2397) Type of voice coil material is important..Be better than Titaniam or Aluminium.....A true Tracktrix is hard to find,,,The JUBE 402 is not a true tracktrix
 
Let me reword it a bit.

My understanding from reading posts made by others who know more than me (some by EE's, some by Roy)...

A 2" horn will have about 1/4 the distortion that a 1" horn has because the area of the 2" is 4 times larger than the throat of the 1".

I'll let others debate if a 75% reduction in distortion is an issue of diminishing returns. Having made that change, I can vouch that for me it was a substantial difference.

(note that I've not said anything about costs because I know the horns probably cost more and the drivers cost more)

I not sure if I understood the Fastrac K horn completely, but doesn't it have an adapter to be used for the 1" K55V driver? Which then would allow a purchase down the road for a 2" driver to be used with it if desired. In other words, it is not necessarily an expense that needs to be put upfront right away? Correct?

Secondly.... I believe we would have to consider the depth (10ft.. can't do better in my house) of my listening area, and if there would be an actual benefit due to the short distance.

With all due respect Coytee..... How do you arrive at a figure of 75% distortion reduction. I don't see the math in that. 1/4 of the distortion is only 25%..... so there must be more factors that are considered in the calculations. Also .... it is important to know the amount of steady state distortion to be expected from the K55V driver. I understand from my reading that it's a pretty good one. Is it less than 1% harmonic distortion? Then a 1/4 of that might not be worth the expense and below audible let's say with Queen played very loud in a 10foot room........:)

It's late and I'm rambling off thoughts...... As always thanks for your input......... and I look forward to your response.
 
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With all due respect Coytee..... How do you arrive at a figure of 75% distortion reduction. I don't see the math in that. 1/4 of the distortion is only 25%..... so there must be more factors that are considered in the calculations.

If item "A" has distortion that is "100" and item B has 1/4 of that distortion, then item B has a distortion level of "25"

So mathematically, we have (25-100)/100 = -75 reduction

It might not be correct from an engineering perspective and, I didn't stay at a Holiday Inn last night but that's how I came to the conclusion.
 
I understand from my reading that it's a pretty good one. Is it less than 1% harmonic distortion? Then a 1/4 of that might not be worth the expense and below audible let's say with Queen played very loud in a 10foot room........:)

I've never experienced any other horn in Heritage than the stock K400/401. Indeed, I've owned stock LaScalas (K400) since buying them new in 1979.

Jumping from my now sold Khorns to a 2" horn....

I guess it depends on volume. The sound I hear at loud levels is better than my Khorns at loud levels. What gets interesting is, I can then go to 'stupid loud' levels, the Khorns (with the stock K401) lost it while the 2" horn just keeps cranking it out sounding excellent.

To repeat, I've never heard any of Dave's, Bob's, Greg's or anyone elses offerings.

I do think if the horn you're getting allows you to put an adapter on it for the K55 and later on, yank it off for a 2" driver, you're good to go. You could borrow a 2" driver and give it an easy side by side. The sound from the larger horns sounds so effortless. Just make sure your wallet is ready :D Once you go larger format horns, it's easy to get addicted & revisit the upgrade path. This is why I simply urge folks to try them first.... cut out a lot of the dinky middle steps in between & save some cash and time. :D
 
YES a modified TRACKTRIX,,, Its mostly straight sided conoid, With a tracktrix mouth,, Supposed to lower lip diffraction distortions..
 
making the jump from a small format driver to a large format driver (1.5" - 2" diaphragm to a 3" - 4" diaphragm) was a deal changer for me and one in which going back is not much of an option. The lower level of distortion is significant with the larger diaphragm designs. Look for sota designs like the EV DH1A or the large format JBL on the used market they represent superb value. If you really want to stay with a small format driver then get a good one like an EV DH1506. Experience the big stuff once and you want want the small stuff after that. Just my two cents. Best regards Moray James.
 
If item "A" has distortion that is "100" and item B has 1/4 of that distortion, then item B has a distortion level of "25"

So mathematically, we have (25-100)/100 = -75 reduction

It might not be correct from an engineering perspective and, I didn't stay at a Holiday Inn last night but that's how I came to the conclusion.

Ah.... I wasn't looking at it from that direction late last night.....
 
............. I do think if the horn you're getting allows you to put an adapter on it for the K55 and later on, yank it off for a 2" driver, you're good to go. You could borrow a 2" driver and give it an easy side by side. ......... :D

Coytee.... I was wrong about this. Here is AL K's response:

"The "K" is a 1 inch horn. It will work with the K55 by using a simple adaptor. It will NOT accept a 2-inch driver.
The Eliptrac 400 is a 2 Inch horn. It can be adapted down to a 1 inch and then to the K55. Dave doesn't like to do that though. He thinks you should go directly to a 2-inch driver with the Eliptrac 400."

Since I'm relatively newly retired and on a fixed income, I believe it's best to go with the Fastrac K horn using the K55V driver. That is when and if I make the decision to replace the original mid-range horn. So far I haven't heard from many forum members who actually have it installed. But I'm leaning toward getting it. I would like to hear some testimonials if they are out there.

Thanks again.
 
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that is a good point but at a number of compromises for those who might wonder low end bandwidth will be less cost will be much higher. I don't know off the top of my head what the distortion of an EV DH1506 is but with an original aluminum diaphragm I expect it is pretty good for a 2 inch diaphragm it sure sounds good and is a stellar performer for the money they go for these days. You can also look into the JBL 1.5 inch exit Be 435 with a 3" diaphragm can be had for cheap used 500 - 700 a pair in excellent condition. The Big 4" diaphragm JBL can be fitter with Be diaphragms as well only wish Be diaphragms were available for the EV DH1A oh well. Are there new Be comp drivers out there which don't cost an arm and a leg? Best regards Moray James.
 
Radian 950 Be,,,Useing true extant phrams or 950 Al... with 5 slit phase plug are good for those on a budget,,,PATTEREND after the TAD BUT LOWER IN PRICE,,,Great sounding,,,, The K55 is a junker siren driver,,,Allways has been,, PWK ALLWAYS went for the cheap way approach,,,As I told that to his face,,
 
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