Dual-500 king of the Castle

Davis...that book is an eye opener....found mine in a BARN full of audio equipment of a guy that went to prison and his wife was saying just get the shit outta here...15 miles west of Gillette in the boonies...
Closing this loop -- good news! Both books arrived, I'm a happy camper!

Sound Reinforcement & Audio Measurement handbooks.JPG

Excellent additions! Looking through the sound reinforcement book, Section 6 is titled "Sound Indoors", and pretty much picks up where we left off. Great stuff -- again, thanks for the tips!

3D
 
Are you gonna use an active crossover and tri-amp or passive crossover. I tri- amp with a 700B driving the woofer and vacuum tubes in the mids and tweets
I am going to tri amp Mark. It will be crossed with a couple of Rane AC-23 electronic crossovers. The Rane has a 24 db roll off per octave and there are 41 steps in the cross over frequency.

To set it all up the left and right( k-horns) may use the DBX driveRack PA2 electronic crossover as it has variable slope with up to 48db rolloff per octave and longer time delay settings than the Rane. We’ll see which is best.

I will Use two dual 500 using one channel for low range and one for the squeaker. The BMS have 16 ohm voice coils so this should work. to finish the highs will use 400 ll with a G board for tweeters. I am doing a combo stereo and surond sound set up. Center will use one 700 and one channel of a 400 in same setup With a Rane AC22 running in mono
 
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Do any folks using steep slope crossovers have concerns with the far reaching phase distortion associated with steep filter slopes?
 
I was thinking that myself as I read Grappelsaw's post. Steep crossovers seem to suffer more from phase issues. Part of the reason the Thiel crossovers are so damn complicated (in addition to the sloped baffle).

And I further suspect you need fairly exotic equipment to identify it is happening. I don't know that you would pick up on it audibly, unless you could A-B between phase distorted and not phase distorted. The "ambience" setting on my boom box sounds pleasant and is using this technology to do so. So, it wouldn't necessarily sound unpleasant, but it would not be a faithful reproduction of the source (which is my goal unless using old receivers).
 
I was thinking that myself as I read Grappelsaw's post. Steep crossovers seem to suffer more from phase issues. Part of the reason the Thiel crossovers are so damn complicated (in addition to the sloped baffle).

And I further suspect you need fairly exotic equipment to identify it is happening. I don't know that you would pick up on it audibly, unless you could A-B between phase distorted and not phase distorted. The "ambience" setting on my boom box sounds pleasant and is using this technology to do so. So, it wouldn't necessarily sound unpleasant, but it would not be a faithful reproduction of the source (which is my goal unless using old receivers).
Jim you may be right
However I will use the drive rack PA 2 to do all this for me It is computer controlled right from my iPad
It uses a precision microphone that has been measured for inaccurate readings then offsets get put into the DBX unit

just stand back and see what it comes up with we will know soon after the horns are ready I can record these settings from the PA-2 and input them into my Rane crossovers and equalizer if I want to use them accurately

google the DBX PA2 and see what it can do Jim I hope You will be impressed
 
Do any folks using steep slope crossovers have concerns with the far reaching phase distortion associated with steep filter slopes?
These crossovers I will use have the ability to adjust for the shift with time delays in each range
 
That is pretty sweet. I definitely want to see that output when you start dialing it in!

And Rane is decent mid-level studio-grade gear; really quite good for 99% of those who need it. That should work out fine with what you have planned.
 
I have an Ashly XR77/18 3 way stereo crossover that I've had for 30 years and it still works like the day I bought it. With the Fastrac 400 horn with the BMS 4592 as midrange I have it attenuated it significantly lower than the woofer and tweeter because of its efficiency
 
I have an Ashly XR77/18 3 way stereo crossover that I've had for 30 years and it still works like the day I bought it. With the Fastrac 400 horn with the BMS 4592 as midrange I have it attenuated it significantly lower than the woofer and tweeter because of its efficiency

Excellent! I hope to have something like yours in a few weeks.

I got the 16 ohm diaphragms thinking, right or wrong unknown yet, that would attenuate them as little. We will see
 
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So the King has new life

here are residual noise
A channel is left
B channel Right

1K across inputs and 8 ohm load on outputs.

two reading for each as lower numbers are at low rail and the tad higher numbers are at high rail
New better results using dead short on inputs4CB3909C-7136-4FDD-A821-65260C0EFA35.jpegF6343CB1-1E30-428E-9375-F87C1FEB8F58.jpegB34F632A-41F1-4039-9BA0-51BE1FB622DC.jpegC8F90CF3-5D9A-476B-8357-051C7E77275F.jpeg

having great success on my resent 700B build I wanted to revisit the grounding topography of this wonderful amp. I applied the lessons learned and I am most pleased with the results. I will be guiding Spencer to apply this to his amp.

Right low rail 110uV
left low rail 208.7uV
right high rail 123.4 uV
left high rail 265.5 uV3DF46B02-530D-42EF-BF5A-022F4814F6A6.jpeg
 
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New better results using dead short on inputsView attachment 64684View attachment 64685View attachment 64686View attachment 64687

having great success on my resent 700B build I wanted to revisit the grounding topography of this wonderful amp. I applied the lessons learned and I am most pleased with the results. I will be guiding Spencer to apply this to his amp.

Right low rail 110uV
left low rail 208.7uV
right high rail 123.4 uV
left high rail 265.5 uV

Grounds matter...
 
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