Panelhead

That is a good fact to know. Never seen or heard of the KP-480. Raising the La Scala is a good idea in my setup. But I am thinking about a foot. Using a high quality active sub now. I like rolling in the sub at a low frequency. With the filters dialed in the crossover the sub cannot localized. I listened for a couple hours yesterday and could not tell the bass was not coming from the LS. Even on some tracks with heavy bass lines. The single sub sits hard stage right. The sub does not add much to many tracks. I like sacred music and most is choral without a lot of accompaniment. But on some types it really adds power and feel.

There are several methods for implementing a digital volume control. My interface uses the dac chip attenuator. This is transparent and offers excellent tracking. But causes resolution to drop at high levels of attenuation. I have to think your Mac uses a digitally controlled resistor ladder. It is very different than how a dac chip does volume control. And since I have a pair of Heresy iii and La Scala’s, the footprint difference is huge. The LS are larger than they look.

I have switched to Canare. It is insane expensive, a dollar a foot for the woofer run and 31 cents a foot for the mid/tweeter. This is Star Quad construction. The AK6 and AL5 come wired internally with a different star quad wire. If I ever upgrade speakers to AK6 or AL5 the wires will match. It is a 25 dollar set of biwire cables.

I use a My_Ref, a diy build. Extremely low noise design, around 50 solid state watts. Had an issue with the volume not matching an active sub. Replaced the input transformer on the amp to “fix” this. Was using a 1:1 transformer to convert balanced to single ended. Swapped in some 4:1 input transformers (600 ohm/10K) to step down the voltage 12 dB. This is equivalent to changing the LS II from 105 dB efficiency to 93 dB. Volume balance between the La Scala and sub is much closer now. A low gain amp sometimes will work better with horns. Like was mentioned just dropping the horns in a normal system will end up with the volume pot adjusted from 1 to 3 out of 10. Tracking can be poor at this level. A digital volume controller is even worse when dropping 60 - 70 dB. Throwing away most of the bits.

The H III was so good I moved on to LS II. No looking back.

Better Records has been touting their better sounding lp’s for at least 20 years. If you think they sound better, they must.

How long is it? The able to the tweeter is about 2 feet long. The cable to the midrangeis about one foot long.

The passive biamp might match up better if you were using the same amps top and bottom. The current setup is running both amplifiers full range into bandpass limited speaker load. If you can, look into a software crossover to bandpass filter the amplifier and not the drivers. I use one that allows adjusting; frequency, slopes, levels, and overlap. All done with 64 bit precision. The Duo may require a little padding down to match the output of the bass cabinet.

I have to comment here; Roy deserves complete respect. He is more committed than all of us. This is still a corner horn. If you want a speaker desired to operate in free space, get a La Scala and give up the last 20 Hz. The support (isolation) looks a lot like the rubber pucks used between the bass cabinet and top hat of my LS ii. May not be fancy, looks fine to me, and isolation may be a goal.

My limited experience is that horns are forgiving. I once made a pair and installed an internal panel off at one end by over 1 1/2”. Should have ruined the expansion rate. The two cabinets sounded and measured the same. Never tried to fix this issue. Used them happily for several years.

Does Guitar Center or another music store stock these? I would like to pick one up.

If this is an improvement over a SL-1200 Mk II I would not worry about rumble. A better motor and speed controller seem to be part of the redesign. Rotational stability sets these way ahead of most belt drive tables. I do not spin many records. But hope to once retired.

That turned out very nice. Great look.

My amp thoughts on this is to connect one speaker with the - to ground and the + to the four ohm connection. Connect the other speaker with - to the four ohm and the + to the sixteen ohm. It does not parallel the speakers across any of the output transformer. Compare this to the other connection options. I have to think it will sound better.

It is great to see that big smile when talking about how “lifelike” the K-Horns sound. Continue on, there are additional development advances for you to identify, refine, and implement.

The center tap of the output transformer is the 4 ohm output. Using this to “bridge the two speaker connections. Transformer impedance changes with the square of the turns ratio.

One way is connect one to ground and four ohm. The other to the four ohm and 16 ohm outputs.Try this.

One tip, take a screw and go to Home Depot, Lowe’s, or even better a True Value or local hardware store. Replace all those steel screws with brass screws. Steel has no place being in the signal path.

Some speakers use the box resonance to fatten up the sound. The output from panel flex is low, but the surface area involved multiplies the level. I was thinking the 19 ply birch was 5 x 5’. Good stuff. I bought all mine at Home Depot. Doubt they stock it now.

Try to find a cabinet supply company. Usually there are suppliers around. Cabinet shops require higher quality plywood than the HD and Lowe’s products. I used some lumber core Birch about 25 years ago. This was impressive stuff. Later started using European 19 ply that was void free. But the sheets were not 4x8’.

Was planning on a single 6’ tapped horn to replace sealed pro subs. The size difference has postponed this project. The weight is about the same. The horn is four times the size. Think people called it the coffee table sub. I was going to have it rotated 90 degrees and call it a sofa table sub. With sealed box the key is to cross low and steep. I use 60 Hz and 18 dB slopes. Played with 6 and 12 dB for low pass. Changed back to both at 18 dB.

I think the 22 mm will make a better option also. Hate to say it, but keeping the exterior dimensions constant will not make any difference. The internal dimensions of the Cornwall will be 8 mm less tall, wide, and deep. That is 0.315 inches. The TS parameter variation in drivers is much wider than this change in internal volume. If they were mine the internal dimensions would be as close to spec as possible. I am OCD about things like this. Made a much larger mistake than this in a horn cabinet once. One was per spec, one was off. They sounded the same. Best I could tell they measured the same. Cabinets are very forgiving.

Dave, The slope of the crossover is different. The steeper slope is better measurement wise. Some feel the lower order crossovers match better at the crossover frequency and cause less phase shift. I like the lower crossover point and steeper slope. Have owned speakers with first order crossovers and speakers with 2nd, 3rd, and 4th order filters. Implementation seems to be the main factor. Well done they all can sound good.

This circuit would be better if it only bypassed the CL-90 after charging up the filter caps. That is a simplified inrush current limiter and a mechanical bypass. Some large solid state amps do the same with transistors. Initial series resistance in a pass transistor and then it drops to almost zero. That circuit handles turn on surge. Offers nothing once the relay is closed. A component failure can take out the rectifiers, transformer windings, or home circuit breaker.

Rather than stream I use an optical Thunderbolt cable to connect computer to dac. Use a 33’ Cable now. Have a 100’ for running to other rooms. Got to believe a 20 GB/sec hard connection is cleaner than the air waves in my home. But I am old fashioned. Got more wireless devices than I ever dreamed; router, phones, tablets, printers, tv, and computers. One less can only help. I have an old install of A+. Quit using at least 3 - 4 years ago. Only use Pure Music app. Like the 64 bit crossover and integration to Pure Vinyl. It also only updates every year or two. A+ used to update a lot. Several versions a week at times. Not sure the last few years.