coolhandjjl

The fact that the noise went away when installed in another room is key. Transformer from a door bell. Metal vent in a chimney. Metal ductwork. Undischarged capacitors from other devices nearby even if unplugged. These are all things I look at when I have RF or EMI noise when I play my electric guitars. I have a tri amp hi-fi system consisting of a mix of solid state and tube amps. Some amps are three wire A/C, some are older two wire A/C. Speaker efficiencies up to 110 dB. I have a barely detectable ground loop noise from one of the solid state amps. The tube amp has a tiny bit of either tube rush or EMI noise, possibly from my active crossover's transformer. (Not sure which it is) However, I do enjoy the system.

Late to this topic. If you are still considering filtering your line voltage, don't bother with Furman or other devices. I suggest bridging a 15uF X2 cap across the white and black leads on the outlets you are using. You can get the X2 caps at rat shack.

SOLD: BMS 4552 1" Compression Drivers, 1 Pair. This is a bolt-on style of driver, however, thread-on adapters are available if you horn is threaded. Some folks have had great success using them on the Altec 811B horns down to 800Hz. Poly diaphragm 1kHz to 20kHz 8 ohms Neodymium Magnet 113dB/m sensitivity $150 plus shipping for the pair.

That is good to know. Did Klipsch then adopt the higher quality caps in their stock network? So many products even aside from audio are compromised by bean counters and marketing guys in their efforts to hit price points. Reminds me of gear heads in the 70's who blue printed their engines so they'd perform as designed.

Yep. I'm happy. Marantz does fine for me. If there isn't much to be gained, I wont mess with it. I've posed that same question amongst the varoius forums myself. I have two systems. I did some tests without any preamps, different preamps, swapping different DAC's amongst the systems, etc, etc. (Both my preamps have been serviced, tested, caps replaced as needed, so on and so forth.)System synergy is often underrated. A preamp does have a sonic footprint, and I favor the sound of Marantz. Here's what I found: My basic system, which consists of Marantz 250M solid state power amps and JLB L100 12" 3-way speakers sounds best "to me" when used with my Marantz 3800 solid state preamp. My uber system, which is a triamp system with Mitsubishi DA-A15DC solid state power amp on the LF horn bass bins, a Rotel RB-991 solid state power amp on the dipole tweets, and a Dynaco ST-35 tube power amp on the mid horn sounds best "to me" with my Marantz 3300 solid state preamp. There are simply way two many permutations possible to be able to test everthing and still have a life. Add to that, the fact that doing audio A/B tests is a flawed concept to begin with. If it sounds good now, I'd stick with it.

Is having perfectly even response from the mid to tweet the be-all and end-all? I will go out on a limb here and say no. If your are crossing below 6kHz, perhaps, but if you are crossing 6kHz or above, a slight drop in overall tweeter output may be more comfortable sounding.

So for us noobs, that means....?

I've a pair of BMS 4552 1" mylar diaphragm compression drivers from an old project laying around. I was considering blowing 'em out on eBay, but perhaps I should give those a shot with Dave's new HF horn.

I tri-amp, and fitting into a Khorn, Cornwall, or other established physical dimensions is a non-issue for me. Given that size and efficiency are not relevant to me, what should I be considering? Still the DE10, or is there benefit to the 120 or the CT125?

I've wondered that myself until I realized that the 3D medium itself may have a resonant frequency within the pass band. That's the beauty of MDF horns, any resonant frequency is well below what anyone would run them at .......well until now..... ;-)

Right on. It's all about proper diaphragm-to-air coupling that makes it work.

Some people complain about ringing in aluminum or cast metal horns. Others complain about honking in plastic horns. Now whether or not those issues indeed exist with metal or plastic horns is something that will be debated until the end of time. The advantage of using wood or mdf is their resonant frequencies are below the horns range. So no debate needed. Dave is indeed the new horn guru. I've learned much from his tireless efforts.

The best thing I did to improve my sound was move the mid/tweet x-over up to 6k. Apparently the original K-Horns were at 6k. I read an article a couple days back a member had linked about keeping that 400~6k range handled by one driver. Very enlightening. Lots of superior tweeter & horn combos available all with their respective unique polar patterns, but crossing at 6kHz seemed to be the more important factor, polars be damned. (unless you have a HF horn that really collapses drastically between 3500Hz and 6kHz.)

There is so much truth to that. I have personal experience with that very situation.

I triamp using a TDM 24CX-4 (Madisound version) It's internally jumpered to act as a stereo three way. 24dB/octave LR topology. If yours is also 24dB/octave LR, you may be able to get by w/o time delay. And since the mid and tweet on yours is passively crossed, the closer tweeter is not time delayed anyway. If the bass to midrange tweet bothers you, and you can't time delay, perhaps there is a 48dB/oct module you can have installed in your Marchand. Bi/triamping is a great way to go with horns. While I am not running Klipsch gear, my bass bins are horn loaded, mid is the Eliptrac 400 tractrix horn, and my tweets are Linaeum LS 1000 dipoles. The tweets are so much lower in efficiency than my bins and mid horn, triamping was the only way to get enough power into them. Initially, I used a calibration mic and software to set the crossover points and levels. That got me close, or so I thought. Then I began to trust my ears and go that route instead. Glad I did.

No, not versus, via. The CNC machine is programmed to cut according to Dav'es tractrix horn shape. The CNC machine cuts out a series of progressively smaller sections on a 3/4" sheet of MDF with registration holes in the corners of each slice. They go together very easily. Dave's horns are very consistant. Don't know why they wouldn't be.

I've read many articles relating to people damping horns, whether they be Klipsch, Altec, etc. I read one article where a guy was coating the exterior of his Altec 811's with a heavy mix of bondo and sand. Perhaps that is why MDF has become such a popular choice for DIY horn designs. Horns are easily made in slices via a CNC machine, and its resonant frequency is so low, it's inaudible. (Dave H, I don't mean the designs, prototype, or testing is easy. Based on what I have read here, it's apparent that you spend countless hours perfecting your horns before someone like me can buy a kit.)

Actually the resistance is frequency dependant. Higher frequencies move out to the outer surface of and use less of the wire. That's the real point of the table.

The table is not about 12 AWG wire not being able to deliver low frequencies down to 20Hz.

I think you are interpreting it backwards. For higher frequencies, there is a tendency for the current to flow more outwards towards the skin of the conductor thereby using only part of the wire. So if you want 21kHZ, use 18AWG. If you use 12 AWG, you will see signal drop due to increased resistance. This makes wiring a one-way a bit of a challenge ;-) http://diyaudioprojects.com/Technical/American-Wire-Gauge/

I have a gut feeling that folks like the multi-cellular Altecs because the dividers help dampen the the horn's ringing rather than any acoustic benefits of multi cells. On their plain ones, some were dipped in tar, some people coat them in bondo, set them in sand, every trick in the book to knock out ringing. They look cool, but IMO, that's where it ends. (Hopefully I don't start WWIII here.) There's a gazillion horn makes out there, some simple, and some with complicated veneering and lathing. And 99.999999% are not multicellular. I'd say they are all un-multi-cellular, but that one guy here will find one custom made one that is multi cellular and post it here. Dave's Eliptrac 400 is a 2" tractric design horn, 400~20K. Lots of folks here have them are they are the real deal.

Those look sweet. Guess I'll have to start all over again []

Aren't Heils ribbons?

Huh? We already know it is an Eminence APT-50, and Bob Crites mentioned his CT125 uses the original APT-50 sourced from the manufacturer.

Workin' barefoot! Love it! Everything looks great!