What can you do with ONE WATT?

[ClaudeJ1]

Why having all horns from sub to tweet really rocks!!

OK, so keep my Avatar in mind when your
read this. I have a separate amp for my bass bin, getting the
receivers pre-outs because I need about an extra 5 db of gain in the
FH-1 with K33's vs. the top section driven by my AV receiver amp
(K402/K1133 with QSC/DE-250). Also need a certain amount more gain in
my Tapped Horn sub with the amazing LAB 12 woofer. Because my
receiver sets up the relative gains against an 85 db industry
standards when it measure at my sweet spot, all this is taken into
account by setting the levels there. Because the average and dynamic
levels of CD's, DVD's and Blue Rays are all over the place, the only
to maintain a stable level (so I don't piss off my neighbors) is to
use a db meter before a music or movie session. The reason I post
this here instead of the HT section is that my system setup auto
detects my source in the Panasonic Blue Ray player and sets up for
2.1 or 5.1 by itself. The majority of my time is spent listening to
2.1, hence the post here. The typical setting on my somewhat obsolete
Onkyo AVR typically ranges from -20 db to -30 db setting on the
level control (Right and Left channel are set to -12 db internally
after Audyssey calibration, for a total of -32 to -42 db nominal
against the receiver's supposedly full output, not including whatever
"headroom" they put in there).

Setting up some Jazz music at about
77-85 Decibels average at my sweet spot on the couch, (slow C curve
on my Radio Shack DB meter) I whipped out my digital voltmeter and
measured at the speaker terminals of each section on the Right
channel, plus the sub. I knew I was using very little power before I
began, but now I can put real numbers to it.

I had a Jazz CD with heavy electric
bass content, so I set the average level to 3 tracks total to my
usual level of satisfaction, which is usually -23 db setting on my
receiver (Right and Left channel are set to -12 db internally after
Audyssey calibration, for a total of -35 db nominal). then I went to
the track that is the loudest on there with the most bass and did my
measuring.

I'm not sure about the response time of
the meter, but I looked for the highest voltage value detected and
rounded up. At the Xover terminals (feeding the two top horns'
capacitors, I got 1.5 volts on the sub's LAB12 terminals, 0.36 volts
on the FH-1, and 0.28 volts on the treble section. The are the
highest readings and most of the time they were less than this.

So the mono sub's, which has it's own
amp fed from the "sub out" on my receiver, and set to -6 db
internally by Audyssey, according to ohm's law ( Voltage squared over
average impedance of 6 ohms) yields 2.25/6 ohms=0.26 watts (about 1/4
watt of power). Similarly, the 5.6 ohm K-33 needs 0.130/5.6ohms=0.023
watts (23 milliwatts), and the treble section is .078/8 ohms=0.010W
(10 milliwatts). PWK told me to add 17 db headroom, which he measured
from his own live symphony recordings. If we double that amount, and
round up to a plus 20 dB headroom, we need 100 times the power to
achieve it. This means my receiver will most likely never put out
more than 1 W on the highest peaks in my 15x18 foot room with 7 foot
drop ceiling on the K1133/DE-250 compresson drivers (since it's
100W/channel, I still have another 20dB headroom on top of it, it can
NEVER clip). The K33 will see a peak of 2.3 watts, and the LAB 12
will see 26 watts peak from a 200 watt per channel amp, with only 1
channel used. Even if you add another 10 db (yet another 10X more
power) that may be needed for the +10db in the LFE channel from
movies (requiring 1,000 X more power than my measurements), it would
mean a 260 Watt peak requirment.

You can see that in an all-horn system,
the subwoofer channel potentially needs all the power and the rest
can be driven by flea powered amplifiers. How many guys that have
Tuba HT's that do a 20 Hz sine wave test at 10 Volts are flexing
their drywall and windows?

Now you know why large format horns ALL
have ridiculously low distortion and wide dynamics. The voice coils
never heat up and behave in a high distortion, non-linear manner from
thermal compression.

[ClaudeJ1]

I remember having a Radio Shack peak dB meter on my ridiculously overpowered Khorns when I was in my early 20's. I sold my 200 WPC amps and replace them with 75 WPC, and even THAT was overkill, although I used to listen TWICE as loud (10 dB more than I do now) to satisfy my young ears.

I think it's a combination of wanting to keep my hearing for as long as I can, but MORE IMPORTANTLY, the extra dynamics and detail I get vs. the old K400/K55V with K77 twwets that I had for years required twice as loud to get it to sound "right."

Now it sound so very "RIGHT" at 10 dB less power or 1/2 as loud as I used to listen to, even though I can go much louder than before with my current setup. Kind of ironic, isn't it?

[Cut-Throat]

Nevermind.

[ClaudeJ1]

Nevermind.

Is this shyness or indifference? Or, perhaps a warning to others? LOL.

BTW, I like your avavatar. What is you Xover frequency to the big Altec? Does it do 300 Hz. like a 311?

[Quiet_Hollow]

At the Xover terminals (feeding the two top horns' capacitors, I got 1.5 volts on the sub's LAB12 terminals, 0.36 volts on the FH-1, and 0.28 volts on the treble section.

+12 dB in the bass region. As many will agree is the the most satisfying for music playback. []

You can see that in an all-horn system, the subwoofer channel potentially needs all the power...

This a given for almost any system. It's where all music energy typically lies, in addition to simply not having enough sensitivity down there in most instances. Even so, 10V across a Table Tuba or a tapped horn is peanuts compared to the direct radiator approach.

This means my receiver will most likely never put out more than 1 W on the highest peaks...

Having the meters and data on-hand to prove that your stereo is a lethal weapon...priceless [Y][]

[ClaudeJ1]

At the Xover terminals (feeding the two top horns' capacitors, I got 1.5 volts on the sub's LAB12 terminals, 0.36 volts on the FH-1, and 0.28 volts on the treble section.

+12 dB in the bass region. As many will agree is the the most satisfying for music playback.

You can see that in an all-horn system, the subwoofer channel potentially needs all the power...

This a given for almost any system. It's where all music energy typically lies, in addition to simply not having enough sensitivity down there in most instances. Even so, 10V across a Table Tuba or a tapped horn is peanuts compared to the direct radiator approach.

This means my receiver will most likely never put out more than 1 W on the highest peaks...

Having the meters and data on-hand to prove that your stereo is a lethal weapon...priceless

In my case I have it pretty flat over the entire spectrum. The treble section is in the 108-110 db/Watt range of efficiency, the bass horn is maybe 105 without the 1-2 db loss of a choke, and the subwoofer, I'm guessing is only about 95 db efficient, so it needs about 13 db more drive than the treble section. So the +12 db of power you mention only serves to equalize the differences in efficiency. I originally wanted to build the v3.0 LAB horns (Brad Litz mod. from Danley's original design), which are 108 db/W horns, but I'd have to go back to 4-way stacks in the corners...............been there, done that, prefer to stay 3-way.

Most of the music centers around 440 Hz. according to many spectral charts and is most critical from 100-10Khz. according to Dr. Earl Geddes' research. If the midrange is where we live, then the K402 is the best midrange horn I have ever heard. E pluribus unum. I guess, according to my numbers, I can reach peaks of 125 db with no problem except ear bleed.............................so yes it would a weapon of torture depending on the type of music.

[NOSValves]

Nevermind.

Is this shyness or indifference? Or, perhaps a warning to others? LOL.

BTW, I like your avavatar. What is you Xover frequency to the big Altec? Does it do 300 Hz. like a 311?

Now I found your "shyness" possibility interesting. Cut-throat has never

been known to be shy in the past. My guess is he might be tired of

wearing his finger tips raw from typing the same basic information over

and over again.

[ClaudeJ1]

Nevermind.

Is this shyness or indifference? Or, perhaps a warning to others? LOL.

BTW, I like your avavatar. What is you Xover frequency to the big Altec? Does it do 300 Hz. like a 311?

Now I found your "shyness" possibility interesting. Cut-throat has never
been known to be shy in the past. My guess is he might be tired of
wearing his finger tips raw from typing the same basic information over
and over again.

I find it interesting that you are from Michigan and use the British term "valve" with your PWK derived Avatar. When PWK gave me a tour of the museum back in 1985, (orginal Klipsch building where Khorns were measured and the C.P. Boner Polycylindrical surfaces abound), I noticed a Marantz 8B in the glass case. I said: "Mr. Klipsch, you can't put that amp in there, I'm using one on my Khorns!" to which, he replied: "That's a very good amplifier."

Are you the one I hear about that does wonders for old tube amps??