Cut-Throat

Dean....I know what you mean.....I get very little participation when I asked about Bi-amping. To answer your question....With my 1.4 inch Drivers and Altec Horns, I am -12db down......But you probably knew that, as you helped me build them.

I started a Bi-Amping Project about a month ago. After trying out a Marchand XM66, I settled on a pair of Hypex PSC2.400 Amplifers with imbedded active crossover that you can modify on the fly, with a PC. Using a type 'A' on the Altec Horns and tweeter, and running the Hypex Amps on the Bass Bin. I think you need a PHD in Physics to understand the software for designing filters, but I got it working (I don't understand it yet) with my system and I have got to say it was the biggest improvement I have made to my system since I added the Altec midrange Horns 10 years ago. This is not a tweak, but the difference between a Heresey and a Khorn. I have unlimited headroom with 800 watts per channel Class D on the Bass Bins, with the smooth sound of SET amps 45 or 2a3 Moondogs on the Mids/Highs. It has completely transformed my system. The great news is that the Hypex Amps were less than $800 for the pair at Madisonsound. This includes the Amps and Active Crossovers built into them. This project is for the DIY only! You have to make Boxes for them as they are plate amps and you can't just lay them on their side, Make Neutrik power Cables and XLR cables before you can even start. Then download software and be very comfortable with PCs and such. The Manuals are completely terrible and useless. Also, Madisonsound that sells the amps admit they know nothing about how to adjust the crossover settings. They are set up for 220 volts (they come from Holland) and they don't mention changing to 120 volts....Did I say the manual was useless? Here is a picture of one in the Solid Oak Cabinet I made for it. They do sound Fricken Awesome though. 800 watts and SET amp silkiness.

I used to have Belles with a type A crossover, which I liked. I still use the 45 amps, but I have moved on to Klipschorns with an Altec Midrange and still use a Modified Type 'A'. Simple is good.

Yes, a good idea, and I tried this before and it just didn't sound as good to me.

Well, as you attenuate the very efficient Midrange you increase the impedance. So my 6db down increases the impedance to 64 ohms. But, seeing how the woofer is now out of the equation, I may not need to attenuate it this much any more. Those are the things that I am pondering.

You may very well be correct. That is why I am asking. Maybe I should just build a simple 2 way Crossover to use for this instead? Actually I don't have the 13uf Cap, because I have different Mid Range Horn. I use a 6.8uf Cap instead. Could I just remove the Cap entirely? And then I am attenuating the Midrange with the Autoformer also. So, then I am wondering how much attenuation should the midrange horn be when only using the passive network with the tweeter? I am currently 6db down on the midrange. So, I may need to make some adjustments there as well??

The Active Crossover is only 2 Way. Splits Lows and Highs. I still need a Passive for the Crossover point between the Midrange and Tweeter.

By the "sub", I am assuming that you mean the Khorn Bass Bin Woofer?.......If so, the answer is no. I have the leads from the Woofer hooked directly to the Output of the Bass Amplifier. The Active Crossover is only sending the Lower Frequencies to the Bass Amplifier.

I just left everything as is on the Crossover. I just unhooked the leads from the woofer bin and attached those to the Bass Amplifier. Is this Correct?

My new Marchand XM66 Active Crossover arrived in the mail today. This is my first foray into Bi-amping, so I could use some advice and tips. My system is Khorn Bass Bin and tweeters, with Altec 1005b Horns with 288-16K Compression Drivers. I am using Welborne 45 SET amps on the Midrange/Tweeters and Welborne 2a3 Moondogs on the Bass Bin. I have modified Type "A" crossovers. How I hooked this up was to disconnect the Woofer at the Crossover and connect it to the Speaker wire hooked to the Moondogs. The Ouput of the 45 amps were hooked as usual to the rest of the Type "A" Crossover. All in all I like what I am hearing. My system is much more powerful now, with a lot more Bass. I initially had my Welborne 300b amps on the Bass Bin, but I could not attenuate the Bass enough, so I switched to the Lower Powered Moondogs. I did order some Class D amps that have 50 watts per channel for the Bass, but I ordered them with gain controls, so I could turn the bass down. I currently have the Active Crossover set at 400hz. I am getting a bit more hum from the Active Crossover (Not a Ground Loop). I think at low level listening the system may not be as coherent with 2 amps, instead of one. But I may make it easier to switch from Bi-amping to Single amping in the future. Any Comments or Advice on this would be appreciated.

Another thing to keep in mind is that if these are your first 104db speakers the Amplifiers and Source become even more important. The first watt of the Amplifier is paramount and any Grunge in the source will be ruthlessly revealed. I use 2a3 and 45 SET amps. They only have 2 to 3 watts per channel.

Eric, What is the 'Brute force method' of discharging capacitors? How do you do it?

I learned that Bi-Amping is a very Stupid Idea.

http://sound.westhost.com/bi-amp.htm

Yes, This rating is for the entire speaker. I wanted to know the sensitivity of just the Bass Bin.

Khorns themselves are rated at 104db. But I have an Altec Midrange and Driver that is rated at 109db. So I was curious what the Bass Bin sensitivity rating was.

I think when you get the Cornscalas, you will be amazed at the Midrange Horn!

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Yup, that thing is Fugly!

The better the "Taste" of the wine, the more I enjoy the music. The "touch" of the furniture that I'm sitting in also affects it. Whether it is a big comfy soft leather chair, or a plush crushed velvet couch. The entire 'atmosphere' of the listening room affects the whole experience. I have tried to build my 'man cave' to accommodate the 'experience'.

It may very well sound better, but I know I would not enjoy it much. I have 5 senses and they all come into play when I'm listening to music. Example: If I had perfect sound, but the room was filled with a putrid odor, I'm not enjoying the music. Probably part of the reason Audiophiles like aesthetically pleasing looking components.

Actually just the reverse!.....Most everyone here will be interested in your review. The reason you don't hear much about the Cornscala is that most forum members have not even heard one. It's a rare bird that was just 'created' a few years ago. I heard my first Khorn about 10 years ago, Then Belles, La Scalas. Never have even heard a Cornwall. And almost no one has heard the speakers that I own, because I replaced the Khorn Midrange with an Altec Multi-cell and Altec Driver. Completely Custom Crossover. So I have basically a 1 of a kind. Klispch speakers are very easy to customize and improve, so we do it!

My recommendation is to hold off on any refinishing, until you decide that they are the "Horn for You"......I first had a pair of Klispch Belles, and while excellent, I still lusted after Khorns.....I did get Khorns about 4 years later. But, of course, I had to completely re-design my basement, so that I had proper corners.

Don't rule out the Khorn. They can be as cheap as cornscalas used. I bought mine used. So, go listen to them before you make any decisions. Then you can mod the hell out of them and tailor them to your likings. If you decide you want Khorns, you would probably only have to wait no more than 6 months to find a used pair close enough to pick up. Enjoy your Cornwalls for now, but listen to as many Horns as you can.......And then......SET amps !

Dean, You had mentioned that you preferred PIO in Type 'A's for SET amps. What PIOs do you like these Days? Still Jensens ?