Ok, Andrew, this is allergy something. I would highly advise you in future before you post any discrete updates, questions, and ideas about what you to inform about the holistic objective of your project, sort of a view from 50.000 feet. That what I meant when I asked "what you do?"
Sorry…I had trouble understanding the expression. I trust your allergy gets better…perhaps too much pollen in the air.
About your project. I would encourage you to look for different location for your playback. The 6 feet is not the width where you will be able to host your inhalation of this topology as it will be underperform. Sure we all restricted by space but if you can find different location in your room them you might want to consider it.
I want to inhale the best audio possible…so I’ll look at what I can do in the house. Unfortunately, the family room is the largest I have….plus, it opens to the dining area…and I like to have playback in an open space, not a closed in room with one door. (I think you said you like this also on a post I read on your site). My only other possible option is the lounge room, which is a closed off room with one door, approx 14 x 16 feet (with tallish ceiling of 10.5 foot.)
So, the midbass rectangular horns are 100 to 500Hz. The lower MF horn from 500 to 5000 and the small horn cover from 5000 and up - let call it HF channel. The idea looks OK but the positioning of it very bad. If you have MF run to 5K and HF start in 5K then you shall not introduce any horizontal offset as it such high frequency you'll have a! lot of imaging smearing. I would very much advise to use the MF and HF horns in strictly vertical configuration. It might be a bit tricky in your case. You can drop you MF horn all the way down to upperbass and put HF above or you can locate the HF under the MF. In your configuration both will work but it would require some sensibility to do it in order to maintain the center image in right spot. I need more information to estimate HOW it might be done. The rate of the horns or the diameter of the mouths, the type of the drivers, the listening distance, the type of the crossovers, the high of midbass horn, the music you will be playing, the proximity to the back wall, the space behind your listening chair and etc.
To your questions/points:
Vertical alignment. No problem…I just drew that drawing quickly…with no specific layout in mind. I’m OK with placing the MF horn on top of the Mid Bass. This will make the MF horn approx ear level….not that I go by that rule…preferring a ‘taller’ presentation of sound.
As previously posted -
MF Horns: The diameter of the mouth is 45cm, horn length 40cm (spheric wave tractrix) from Stereolabs Germany.
HF Horn is 1000Hz Stereolabs, 12cm diameter, 6cm length.
MF Drivers: Selenium 2-inch D405
HF driver is Selenium D220Ti
Listening distance: 19.5 foot.
Crossover: Essentially to be decided. I have two temporary approached. Bob Crites has prepared a three-way crossover based on the two Selenium drivers (which he uses for his Klipsch re-builds). Once I get the new three-pairs of amps (two SET, one push-pull for the Mid Bass), I will experiment with electronic (eg mini DSP - yes, I know your views on this!) to guage the best cross-over points, time delay etc. Then I will invest in a quality analogue xover. Note – the new three amps will all have separate volume control, with one of the amps driving a master volume control. I am yet to decide on amp for the sub bass for the two 30Hz tapped horns.
Why 500/5000 cross over points? I selected this range for a couple of reasons. As I outlined in an earlier post, I had enjoyed the Bob Crites two-way (Klipsch) Corsncala horns. These crossed over at 500Hz. I knew that I wanted compression drivers for the critical 500+ listening range…so I stayed with that x-over point. I then thought of adding the HF horn to provider a better high end frequency…even though the two-way I was listening to with 1.4 inch Faital Pro drivers extended quite well to 16,000/17,000Hz. However, I knew that they were not operating as intended. The other reason for this xover mix is to take advantage of a DIY approach to the mid bass horns. I did not have the funds to buy a large sub bass horn…so I needed to build something with moderate size that would easily cover the 100 to 500 range OK. Also, because of costs and ‘simplicity,’ I opted for two round horns only to cater for the MF and HF. Of course, if money was no object, and I had engineering skills to build complex xovers, I would probably have opted for more horns. However, there’s also an argument to try and keep things relatively simple…and remember, this is my first front loaded horn system.
Midbass horn: The height is per the width, 23 inches.
Music: I enjoy a range of music…mostly I enjoy jazz, blues, funk, with mid-range rock (Clapton etc). I enjoy female vocals, eg Eva Cassidy. I don’t like heavy metal, rap etc. I enjoy classical, but I don’t have many recordings.
Proximity to back wall: my listening position is about 1 meter from the back wall.
Hope this helps.