enter altec valencias

a couple of weeks ago the first horns (ever) arrived in my system, in the form of altec valencias. an 811 (800hz) horn with a 1 one inch compression driver (806) paired with a 416 in a largish reflex box. it immediately triggered a reread of everything there is to find about horns in sound practices. here are some first observations:

• the valencias plus an extra tweeter has the potential to be a ‘midi’version of the melaudia system at etf 2006, which i was very impressed with.
• that big woofer really couples to the room. it took a while to tame the boomy bass. they are now with their inside corner 14cm from the back wall, angled in 60˚.
• the horn has a pot to match its level to the woofer. it did not take long to find out why one reads that it is a crime to pad a horn down. it robs life. the biggest crime in audio is wasting music power. i preferred to live with an fully turned up horn, before moving on to tri-amping.
• these horns beam. i hate that. in sound practices nº13 we can read why. the newman criteria predicts that every compression driver rolls of above 3khz. so most horns beam to compensate on axis. my interest in constant directivity horns is sparked. i’d rather switch to my tweeter solution above 3k. now we need the (very) short list of cd horns that don’t suck.
• 15 lousy telephone speaks make for one efficient tweeter. keeps up with the horn. found out that paralleling the tweet to the horn with a cap on the same amp robs life. again.
• aaargh, crossing over at 800hz. if up to now getting the whole vocal range out of a single driver is your goal, this hurts.
• getting some bass means compromises. if you do not want to make compromises, it means living with 16 square meter open baffles, or many more cubic meters of horns. anything else is cheating physics, and means compromised amps to deliver the power required. listening to these compromised amps all the way up to 800hz also hurts. limiting the box + amp bass compromise to 100–150hz is a good idea.
• popping a 150–800hz horn on top of the valencias would be the way to a kick-ass 4-way horn system. for now i make due filling this range with my old speaks (top photo). i put the backs on again.
• interesting: divide the 20–20khz range into 4 equal parts of 2½ octaves. cross-over frequencies: 112hz, 632hz, 3557hz. can’t be a coincidence.
• i need more amps, tube amps. it is quite a different and refreshing to think about creating specialised amps for above 500hz and above 3khz. suddenly cap coupling may be attractive again, with those short, short time constants.