cross over question

[DAX616]

I will be splitting the output of my bez preamplifier using rca y connections between 2 monoblock mk111's and a hafler 220. I will be using a line level passive volume control for the hafler solid state amplifier. My goal is to have a seperate volume for the bass bin and the top end of the k horn. My velodyne hgs 18" sub is involved. I need to use the speaker level connections @ the velodyne due to distance from the amplifiers ( line loss).When connected in this fashion the velodyne has a high pass @ 80 hz and adjustable low pass.I have type aa crossovers (1973 k horns).

what goes where?

Thanks T.C.

[DAX616]

So, I am unable to use the internal crossover in the khorns to accomplish this. Does it breakdown @ the y from the preamp or am I unable to isolate the woofer section of the crossover? If I use an external crossover do I still need the passive volume control for the Hafler ( there is no gain control)?

[NOSValves]

Mark,

While I'm sure your advise on doing it right is the absolute best solution. Its my understanding that there is a way to make this work fairly well for a trial run before you plop down the cash on a top notch active crossover. I agree that for music the subs are just not required but that is my preference.

I'm not absolutely sure how you go about doing this but I believe the existing klipsch crossover can be wired for biamping to cut the full signal going to the top and bottom. The amp running the top will in effect see less load since it won't have the impedence drop of the woofer I would think? Once he has played with this setup and decides he wants to go all out then he could splurge for a active crossover. All he really needs is a way to control the volume to the top or bottom to match or blend the sensitivity difference of the two amplifiers. Not ideal but for a quick dry run I believe it can be accomplished. The if he likes it spend the $ and do it top notch. He just needs to keep in mind that its not ideal and will improve once done with a quality active crossover.

Am I lost?

Craig

[ben.]

One of these is all that's needed. http://www.musiciansfriend.com/srs7/g=home/search/detail/base_pid/182466/

Not the be-all end-all quality wise, but for $90, you'll know if you're barking up the right or wrong tree. Use it between your pre and power amps in two-way stereo mode, and retain the Klipsch network between the squawk and tweet. It has a summed LF out for your sub, too.

[DAX616]

In previous post I have heard of great difficulty matching crossover points using active crossovers.Maybe I should ask the question, why does the original passive crossover in the k horn work better? My aim is not to change the tone or replace the bass bin. I wish to make it louder. In other words bring it out to match the volume of the squawker and tweeter. I have a large room

[Daddy Dee]

One tweak that I've used on my Khorns is to change the squawker to the #3 tap on the autoformer. This will lower the squawker output by 3dbs, thus enhancing the perceived woofer performance relative to the squawker. I don't know if this preference is just the preference of my own ears, or better compensates for the room acoustics... however, when I made this small change it was like enjoying a new pair of Khorns all over again.

[DAX616]

The high pass for the velodyne is set to 80Hz so I set the low pass to overlap that slightly. In the past I have enjoyed the chest thump typ found around 100Hz that the khorns can produce. The velodyne gives tight rich bottom it also allows a volume control. Thanks for the input

[NOSValves]

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On 4/26/2005 11:20:54 AM NOSValves wrote:

Mark,

While I'm sure your advise on doing it right is the absolute best solution. Its my understanding that there is a way to make this work fairly well for a trial run before you plop down the cash on a top notch active crossover. I agree that for music the subs are just not required but that is my preference.

I'm not absolutely sure how you go about doing this but I believe the existing klipsch crossover can be wired for biamping to cut the full signal going to the top and bottom. The amp running the top will in effect see less load since it won't have the impedence drop of the woofer I would think? Once he has played with this setup and decides he wants to go all out then he could splurge for a active crossover. All he really needs is a way to control the volume to the top or bottom to match or blend the sensitivity difference of the two amplifiers. Not ideal but for a quick dry run I believe it can be accomplished. The if he likes it spend the $ and do it top notch. He just needs to keep in mind that its not ideal and will improve once done with a quality active crossover.

Craig

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Mark,

I take your not familiar enough with the Klipsch crossover to comment or I'm lost and you didn't want to say it

Anyone else ever played with this? I could of swore I read that it can be done with reasonable results around here before.

Craig

[DAX616]

This is what I am talking about.

"6.0 Attenuation Networks

Updated 05 Nov 2001 - a reader pointed out that I had made an error in the woofer sensitivity calculation, so this section has been revised - with the correct information this time. My apologies for any inconvenience.

It is rare that the woofer and tweeter (or midrange driver) will have the same sensitivity (i.e. efficiency). The woofer should have the lowest efficiency, since it will require the most power, and any network that reduces the level to the woofer will absorb a disproportionately high power, and will adversely affect the damping factor.

The driver selection is very important - ideally, all drivers will have the same efficiency, and no attenuation will be needed. In the real world, this will rarely be the case. Attenuator networks are a necessary evil - it is immeasurably better not to use them at all, but they cannot be avoided unless the drivers have exactly the same sensitivity."

Any body who knows this stuff feel free to check this sight to see if its credible

http://sound.westhost.com/lr-passive.htm

Has this been considered in the khorn?

[ben.]

Yes. The midrange is already significantly padded in the stock networks. It should be noted that merely changing the autoformer tap also changes the crossover point. A capacitor value change should be made at the same time.

My numbers may be off, but I think a change resulting in an additional 3dB pad results in a high pass of around 200Hz for the midrange, unless the midrange cap value is doubled. Someone please correct me if I'm wrong here. I'm working from memory, and I don't think about this stuff too often. There have been numerous posts on this, so a search would uncover quite a bit.

Regarding use of an active crossover, I don't know what the big deal is. Seems pretty intuitive to me. Setting your crossover points is much easier than with a passive network. Just turn a knob.

[Deang]

Is there a crossover question in this thread somewhere?

[DAX616]

The question is #1 Can you drive the woofer section of the passive network with a seperate amplifier and skip the hardships of an active crossover.The answer I get is no. #2 In reference to the article above, does the klipsch passive network consider the inefficiency of the a 15" woofer when compared to extreme efficiency of the tweeter and midrange.The one post that addresses this says the mids have been attenuated. Granted cross overs are not my bag. People on this forum rebuild and tweak them. I would assume this would be an issue when considering the design of network. The end user hears a baby cry before they hear bass. Am I crazy when I say, the top end can be driven by micro watts but that will not be the optimum power range of a 15"woofer.I think its like trying to start from a dead stop in 4th gear. The crossover has a lot to do with this. How is not a cross over question? I see alot of dancing on this question but I could be so far behind that....