Jump to content

I finally got around to triamping my K-horns


Greg Oshiro

Recommended Posts

Chris--

I spent some time perusing your Belle triamp thread. What measurement system did you use? The plots I saw looked like a real man's FFT box, HP/Agilent or SRS.

I also saw that you used Crown D-75A's for amplification. I'm using Crown D-75(not A). I had to modify the internal grounding to reduce the hum & buzz, but the output stage class B current crosstalk into the low-level stages went up. One of these days I'll get another D-75 and chase all the gremilins... Or maybe gut it and use the bits for a "Really good 5-Watt amplifier".

--Greg

Link to comment
Share on other sites

The plots are Al Klappenberger's (of ALK Engineering) using some sort of hard copy plotter (on the first plot at least) and real test gear. He doesn't have an anechoic chamber, but that's about the only thing he doesn't have. He isn't posting here presently, but he is available from his own website for questions on his equipment.

There is a pretty good thread here on "The Duke" D-45 upgrade thread to dramatically speed up their slew rate, which has been slowed by Crown to assure stability for nasty loads. The D-45 is internally almost identical to the D-75A, with power supply capacitors and PS transformer said to be the only differences. You can get the upgrade list from mdeneen here on the forum, formerly the proprietor and engineer at Juicy Music (e.g., tube electronics such as PCat amps, Blueberry and Peach preamps, etc.). If you can't find him for his parts list, let me know. There have been some parts obsolescence issues with his list from last year, but there are a couple of guys here that have either located the parts somewhere or have found suitable substitutes.

Chris

Link to comment
Share on other sites

Sounds like you have a fun setup. Welcome to the forum.

Do you notice better clarity at higher volumes? I would expect with the time alignment you now have that you would notice better clarity when played loud. There is a lot of overlap in the drivers with the stock passives that can lead to "mis-alignment mush" when played loud.

Link to comment
Share on other sites

<snip>There is a pretty good thread here on "The Duke" D-54 upgrade...<snip>

Chris

I spent way too much time reading the Duke thread... My amps are D-75(not A). Two different flavors: one uses a uA739 (yes, a uA739) in the front end; two use an LF357 in the front end. Pre-historic compared to the D-45A/D-75A that were "Duke'd". My amps have more significant problems than opamps and capacitors.

Link to comment
Share on other sites

Sounds like you have a fun setup. Welcome to the forum.

Do you notice better clarity at higher volumes? I would expect with the time alignment you now have that you would notice better clarity when played loud. There is a lot of overlap in the drivers with the stock passives that can lead to "mis-alignment mush" when played loud.

It is a fun setup. I may descend into tweaking <heck>, though. These DSP boxes are way too tempting to tweak... endlessly.

I'm noticing better clarity at *all* volumes. Reverb tails decaying away are sooo much clearer. The lack of "mis-alignment mush" was immediately obvious at the squawker/tweeter crossover. The woofer/squawker crossover less so. I think the woofer smoothing EQ applied before setting the woofer/squawker crossover made the bigger difference.

Link to comment
Share on other sites

What differences between passive and triamped setups have you folks heard?

My impressions were very similar to yours, especially regarding the tightening of drums and other low frequencies (See thread: Active crossovers in software)

Before you switched to the active crossovers, were you using the original 1980 crossovers?

Regarding amps -- if you decide to replace your Crowns, you might look at some of the home theater amps. I'm using an Outlaw 7075 (very low noise, plenty of power for Khorns), and Emotiva and ATI (who manufactures the Outlaw amps) also have multichannel amps that would be ideal for a triamp setup.

- Bill

Link to comment
Share on other sites

OK. I'll take the bait. How did you get the chart into the post?

1) Reply to post in Belle Tri-amp thread,

2) highlight table in referenced text, and copy into your paste buffer (i.e., "control-c")

3) close edit without posting new reply in tri-amp thread

4) reply to your post in this thread:

5) paste table in reply (i.e.,"control-v")

6) edit the pasted table for your Khorn tri-amp values

7) Hit "post" button, below

Voila!

Chris

Link to comment
Share on other sites

What differences between passive and triamped setups have you folks heard?

My impressions were very similar to yours, especially regarding the tightening of drums and other low frequencies (See thread: Active crossovers in software)

- Bill

Interesting thread. I'm not excited about software DSP for audio running on the main CPU, though. If it's on dedicated DSP hardware on a card, it can work (as evidenced by all The Digtal Audio Workstations out there).

Before you switched to the active crossovers, were you using the original 1980 crossovers?

- Bill

Yes. AA's. I checked the component values when I re-wired the speakers. All was well.

Regarding amps -- if you decide to replace your Crowns, you might look at some of the home theater amps. I'm using an Outlaw 7075 (very low noise, plenty of power for Khorns), and Emotiva and ATI (who manufactures the Outlaw amps) also have multichannel amps that would be ideal for a triamp setup.

- Bill

I checked out the Outlaw 7075 page. That looks really good, especially at that price. The only downside is I need XLR balanced inputs on the amps.

Link to comment
Share on other sites

Many Thanks to Cask05 for the chart format. One of the mid filters wouldn't fit, so see the addition after the table.

I'll post the right channel separately.

Klipschorn - Yamaha SP2060 Tri-Amp Settings (left)

Dec 13, 2011

Assignments

Frequency Band

LO

MID

HI

IN

Connector

OUT 1

OUT 2

OUT 3

Input Source Routing

A

A

A

A

PEQ Filter Settings

Filter 1 Typ

PEQ

PEQ

PEQ

PEQ

Filter 1 Freq. (Hz)

30 Hz

475

3.55Khz

63 Hz

Filter 1 Q/Slope(Q,dB/octave)

4.2

6

8

2

Filter 1 Level(dB)

+10

+2

-7

-2

Filter 2 Type

PEQ

PEQ

PEQ

H shelf

Filter 2 Freq.(Hz)

95 Hz

579

4.25 Khz

5 Khz

Filter 2 Q/Slope(Q,dB/octave)

4.2

4.2

8

6 dB/oct

Filter 2 Level(dB)

-5

+4.8

+7

+0.25

Filter 3 Type

PEQ

PEQ

PEQ

Filter 3 Freq.(Hz)

170 Hz

1.5 Khz

7.1 Khz

Filter 3 Q/Slope(Q,dB/octave)

4.2

5

2

Filter 3 Level(dB)

-8.4

+6

-3.5

Filter 4 Type

PEQ

PEQ

PEQ

Filter 4 Freq.(Hz)

230 Hz

1.06 Khz

10 Khz

Filter 4 Q/Slope(Q,dB/octave)

6.0

4.2

4

Filter 4 Level(dB)

-6.1

-1

+5.5

Filter 5 Type

PEQ

PEQ

PEQ

Filter 5 Freq.(Hz)

300 Hz

1.22Khz

3.65Khz

Filter 5 Q/Slope(Q,dB/octave)

6

10

6

Filter 5 Level(dB)

-2

+3

-6

Crossover

HP Resp(Type,dB/octave)

BW 12

Adj Gc 12

HP Frequency (Hz)

500

6 KHz, Gc=0 dB

HP Polarity (norm/inverted)

Normal

Normal

LP Resp(Type,dB/octave)

BW 12

BW 12

LP Frequency (Hz)

385

4.55 KHz

LP Polarity (Norm/Inv)

Normal

Normal

Delay

Input Delays(ms)

1+2 Input Delay (ms)

Output Delay Value

4.4

6.01

Output Delay Units

ms

ms

Compressor

Comp Thresh (dBu)

Comp Ratio (X:1)

Comp Attack (ms)

Comp Release (ms)

Limiter

Limit Thresh (dBu)

Limit Release (ms)

Output

Level (dB)

0

-10

-9

Polarity (Norm/Inv)

NORM

NORM

NORM

I'm not skilled eough to add rows to the chart...

Add to mid EQ: 3.15 Khz, Q=4.2, gain=+4.5

The "Var Gc" filter is a Yamaha "feature". you can adjust the <gain at the corner frequency=Gc>

Link to comment
Share on other sites

Many Thanks to Cask05 for the chart format. Some of the filters wouldn't fit, so see the addition after the table.

Klipschorn - Yamaha SP2060 Tri-Amp Settings (right)

Dec 13, 2011

Assignments

Frequency Band

LO

MID

HI

IN

Connector

OUT 4

OUT 5

OUT 6

Input Source Routing

B

B

B

B

PEQ Filter Settings

Filter 1 Typ

PEQ

PEQ

PEQ

PEQ

Filter 1 Freq. (Hz)

30 Hz

475

3.55Khz

63 Hz

Filter 1 Q/Slope(Q,dB/octave)

4.2

6

8

2

Filter 1 Level(dB)

+10

+3

-4

-2

Filter 2 Type

PEQ

PEQ

PEQ

H shelf

Filter 2 Freq.(Hz)

95 Hz

630

4.25 Khz

5 Khz

Filter 2 Q/Slope(Q,dB/octave)

4.0

4.2

8

6 dB/oct

Filter 2 Level(dB)

-5

+4.5

+5

+0.25

Filter 3 Type

PEQ

PEQ

PEQ

Filter 3 Freq.(Hz)

170 Hz

1.4 Khz

7.1 Khz

Filter 3 Q/Slope(Q,dB/octave)

4.2

4.2

2

Filter 3 Level(dB)

-9

+5

-4.5

Filter 4 Type

PEQ

PEQ

PEQ

Filter 4 Freq.(Hz)

236 Hz

900 Hz

10 Khz

Filter 4 Q/Slope(Q,dB/octave)

10

2

4

Filter 4 Level(dB)

-5.5

-1

+7.5

Filter 5 Type

PEQ

Hi shelf

PEQ

Filter 5 Freq.(Hz)

290 Hz

2 Khz

3.65Khz

Filter 5 Q/Slope(Q,dB/octave)

10

12 dB/oct

6

Filter 5 Level(dB)

-3.3

+3.5

-6

Crossover

HP Resp(Type,dB/octave)

BW 12

Adj Gc 12

HP Frequency (Hz)

500

5 KHz, Gc=0 dB

HP Polarity (norm/inverted)

Normal

Normal

LP Resp(Type,dB/octave)

BW 12

BW 12

LP Frequency (Hz)

365

4.50 KHz

LP Polarity (Norm/Inv)

Normal

Normal

Delay

Input Delays(ms)

1+2 Input Delay (ms)

Output Delay Value

4.4

6.00

Output Delay Units

ms

ms

Compressor

Comp Thresh (dBu)

Comp Ratio (X:1)

Comp Attack (ms)

Comp Release (ms)

Limiter

Limit Thresh (dBu)

Limit Release (ms)

Output

Level (dB)

0

-10.5

-10.5

Polarity (Norm/Inv)

NORM

NORM

NORM

I'm not skilled eough to add rows to the chart...

Channel B gain is +0.7 dB, this was done so both woofer gains could be set at 0 dB. I was/am not confident in the measurements in the woofer frequency range, so I wanted to easily adjust the woofer level up and down equally on left & right.

Add to low EQ: 500 Hz, Q=10, gain=-10

Add to mid EQ: 6.0 Khz, Q=6, gain= -5

The "Var Gc" filter is a Yamaha "feature". you can adjust the <gain at the corner frequency=Gc>

Yes the input EQis the same on both left and right.

Yes the fractional dB settings are ridiculous. That what happens when the TEF cursor reads out in 0.1 dB incrments. The input EQ gain of 0.25 dB was done by ear. 0 dB was too dull, +0.5 dB was too bright, so I averaged.

Yes there are a lot of Q=4.2. That's the default value and I can be lazy.

Yes the settings are different on left and right. The raw speaker responses were not the same on left and right so the EQ and corssover filters are different. The electrical filter response does *not* matter. The combined response of the electrical filters and the raw speaker response *does* matter.

That was a horrendous amount of typing......

Link to comment
Share on other sites

That was a horrendous amount of typing...

But just think about how much better you feel about yourself now for being such a good guy... [:)] You're right - this is going to take a little time to digest (i.e., different left/right channels, the number of PEQs), but understanding your settings helps a bunch.

Your crossover frequencies are interesting - is there a reason why you chose what you did? I find that the crossover performance available between the tweeter and midrange to be a little less than I'd prefer, so I moved the crossover frequencies up and down a bit and finally settled on 5 KHz, 24 dB/octave L-R (Butterworth squared). The issues with timbre difference between the Jubs on each side and Belle seemed to disappear. I also found that getting the relative channel gain on center channel vs. fronts was pretty sensitive -- more than I'd expect: +/- 1 dB or less. Also, the relative gain on your Khorn driver channels is interesting - bigger than I would have thought.

Richard Heyser's Khorn review article talks about the issues of time alignment of Khorn drivers and what it means in terms of listening. I believe your comments on the change in listenability correlate closely with my experiences tri-amping the Belle. I wish that others on this forum would try out time alignment - maybe they'd divert some of their hard-earned cash away from expensive electronics and turntables if they did. The performance difference isn't subtle and the speakers get much more transparent/realistic sounding.

The bass boost that you use is about the same that many Jub owners are using on their bass bins: 31 Hz, +7 dB, Q=~12. There was a lot of discussion over the validity of putting it in until they actually heard the difference, then I believe reason prevailed and everyone realized that this wasn't such a bad thing.

Looking at your original post, I was a bit put off by the roll-off of the bass bin performance below ~70 Hz, but knowing now how you measured it and also how you EQed the peaking response of the bass bin down on the 63 Hz EQ, etc., I understand now. Getting these settings dialed in must have taken you a while.

When I instrumented my setup some time back, it took me the better part of a day using a laptop running REW, Dx38 crossover, and a DEQ2496 auto-EQ (graphic equalizer), which I used to go back and forth with until the room started to sound much more balanced with the tapped horn subwoofers in the same corners. I transfered the auto-EQ settings to PEQs on the Dx38 sequentially until I eventually took the DEQ2496 out of the loop, leaving only the Dx38 PEQs. Then I checked the FR until both the pink noise auto-EQ didn't change the settings and the REW upsweeps looked good. Then I listened and tweaked a little. The bottom octave from the TH subs (17-40 Hz) became much more apparent and natural.

One of the other guys here mentioned that I "knocked the bass down quite a bit" on the before/after FR plots below 150 Hz. But everything became much more neutral when I did, even though I left a few dB of rising response --> 20 Hz.

Chris

Link to comment
Share on other sites

According to the Heyser Khorn review the bass bin delay is 8.4 ms after the tweeter - I see you're using 6 ms. You might try dialing in an additional 2.4 ms on both the midrange and the tweeter, then listen for changes around 500 Hz. I listen to tenor saxophone (jazz), male voice (baritone or tenor), or electric guitar, but you also might hear it with other instrumentation, too.

EDIT: for others that might read this, the required time alignment between drivers is something approaching 1/10th of a wavelength at the crossover frequency if you listen within a few feet of the speakers (~15-20 feet). This rule of thumb was arrived at by independent listening and evaluation.

For the Heritage series of Klipsch speakers, the upper crossover frequency between the tweeter and midrange is ~6000 Hz. The period of a wavelength of sound at this frequency is

 

P = 1/f, or 1/6000 = 1/6th of a millisecond.

The needed time alignment between tweeter and midrange is 1/10th of this, or

 

Tweeter/midrange time alignment = 1/(6000) * 1/10 = .017 milliseconds or 17 microseconds.

This corresponds to about +/-1/4 inch of allowable driver misalignment (including any off-axis listening misalignment due to vertical separation of the midrange-tweeter horn mouths, e.g., sitting down or standing up).

This is why it is so difficult to get tweeters aligned properly in 3-way speaker designs, and why you need to listen to the time-aligned 3-way speakers on-axis in order to avoid listening to a polar null off-axis between the tweeter and midrange. This tweeter/midrange polar-null off-axis problem is also dependent on the vertical separation distance of the tweeter and midrange in the speaker cabinet: the larger that dimension, the worse the problem gets.

For the bass bin-midrange crossover, the upper frequency is ~500 Hz.

 

Woofer-midrange time alignment = 0.2 milliseconds or 200 microseconds.

This corresponds to ~2.7 inches of allowable driver misalignment. So for the Klipschorn, there is 2.3/.017 or about 14 wavelengths of time misalignment between the tweeter-to-midrange at the upper crossover frequency, i.e., about 140 times too much misalignment.

The good news is that it is possible to remove the Khorn tweeter from its cabinet and mount in a L-shaped bracket to set on top of the top of the speaker, but set back from the front of the speaker to approximately align with the front face of the K55 midrange driver below it inside the cabinet top-hat. This is cheap, easy, and effective. It also can eliminate the "baffling effect" of the tweeter mounted on the back side of the baffle, which negatively affects the tweeter's polar radiation pattern both horizontally and vertically.

For the bass bin-to-midrange crossover region, the actual misalignment is (8.4)/2 or about 4 wavelengths, i.e., 40 times too much misalignment. Unfortunately, there is really no way to physically align the midrange to the woofer since one would have to move the midrange horn/driver assembly (plus the tweeter with it) back about 31.5 inches to physically align with the Khorn's bass bin woofer. Since the speaker is already placed into the corner, one would have to build a pretty interesting looking false corner to correct for this, and you would introduce midrange and tweeter horn mouth masking issues, or increased vertical horn separation distances if you tried.

I hope that you'd agree with me that using a digital active crossover to correct for driver/horn time misalignment and to provide stable and steep crossover filters + PEQ filters is probably the best compromise. I know that the use of an active digital crossover allowed me to use a Belle between two time-aligned Jubilees (w/TAD TD-4002 drivers). I couldn't have used the Belle otherwise, since it sounded too different from the Jubs with its stock passive crossover. This is a really good testimonial, IMHO, since I found nothing else that integrates between two Jubs.

Chris

Link to comment
Share on other sites

<snip>But just think about how much better you feel about yourself now for being such a good guy... Smile<snip>

My altruism is swollen beyond recognition ;).

<snip>Your crossover frequencies are interesting - is there a reason why you chose what you did?<snip>

The crossover filters and delays were selected to yield magnitude and phase characteristics at the measurement mic that sum acoustically to something resembling "flat" and keep the axis of the main radiation lobe perpendicular to the baffle. This was a first-pass and I think the radiation lobe is not stable in the crossover region. I was amazed that I didn't get much corruption by room reflections.

<snip>Also, the relative gain on your Khorn driver channels is interesting - bigger than I would have thought.<snip>

The EQ might be responsible for the apparently large difference. There's a lot of PEQ attenuation in the woofers.

<snip>The performance difference isn't subtle and the speakers get much more transparent/realistic sounding.<snip>

Roger that. I don't trust my ears to evaluate the sound yet. There's too much "I did the measurement/math right... so it must sound right" going on in my head.

<snip>The bass boost that you use is about the same that many Jub owners are using on their bass bins: 31 Hz, +7 dB, Q=~12.<snip>

Q=~12? yikes! I'm extremely wary of high-Q boosting. Once I figure out this measuring LF-in-a-room problem, We'll have to try measuring your Jubs.

In the fourth post in this thread (Hey, how do I link to an existing post?) I detailed my possibly bogus LF measurement method. Got any thoughts on that?

<snip>Getting these settings dialed in must have taken you a while.<snip>

I did it over 3 or 4 days, I think it was a total of 15-16 hours. The reverse-polarity squawker driver made the first 3 or so hours useless. Guess now I'll remember to *always* check that first...

<snip>When I instrumented my setup some time back, it took me the better part of a day using a laptop running REW, Dx38 crossover, and a DEQ2496 auto-EQ (graphic equalizer), which I used to go back and forth with until the room started to sound much more balanced with the tapped horn subwoofers in the same corners. I transfered the auto-EQ settings...<snip>

What's REW? I wouldn't trust any kind of auto-EQ. TEF basically provides a Bode plot of the speaker transfer function(s). At each crossover point, filters and delays are selected to get high-pass and low-pass transfer functions that add acoustically to a "flat" curve through the crossover region and keep the axis of the main radiation lobe perpendicular to the baffle. It's pretty much junior-year EE linear time invariant system stuff, at least when I was a junior... It's probably all digital these days.

There were some anomolies in the raw speaker responses that might be diffraction. I did EQ them out, but that's only valid at the mic position, which is not the listening position. I need to experiment with some fuzzy stuff and see if there are diffraction problems and kill them the correct way... but I'm too busy enjoying what I've done so far.

Link to comment
Share on other sites

Q=~12? yikes! I'm extremely wary of high-Q boosting. Once I figure out this measuring LF-in-a-room problem, We'll have to try measuring your Jubs.

Hold on - I didn't say that I use that bass boost - I use the TH subs when I need that bottom end, and my setup is calibrated for the subs to be working, and that you're sitting in the listening position(s). The bass boost that I mention was provided by a guy who has access to an anechoic chamber.

What's REW? I wouldn't trust any kind of auto-EQ.

REW is "Room EQ Wizard" - freeware available on one of the other AV forums.

I don't trust autoEQ either, so I used it to convince myself that I was going in the right direction with REW and the Dx38 PEQs, then I removed the autoEQ unit from the signal chain after I got the really mean and nasty fr peaks and tilts out of the way.. The issue is not only to get minimum-phase EQ right in a small room close up - it's also to get the EQ right at the listening position. Once you get below the Schroeder frequency for the room that you''re in, you can do a lot with a microphone in your listening positions rather than in the speaker's close field.

I need to experiment with some fuzzy stuff and see if there are diffraction problems...

Yes - I believe that you're right, especially to correct for midrange horn loss of polar control from the midrange's high pass frequency up to about 1700 Hz. Putting fuzz material on the speaker top, and even the front of the speaker will help control this. The floor around the speaker needs something on it to absorb these frequencies also. If you put a fuzz panel on top of the speaker, but let it stick out a little way in front, you may be able to avoid putting stuff on the ceiling.

I'm really not kidding about increasing the delay on the tweeter/midrange to get closer to the actual bass bin delay. I looks as if you've summed your crossover frequencies to the bass bin on a more-than-360 degree phase. I think that you'll get better impulse response if you move it up, IMHO.

Chris

Link to comment
Share on other sites

<snip> You might try dialing in an additional 2.4 ms on both the midrange and the tweeter...<snip>

Chris

No cigar. See the attachment. Note the 544 Hz suck out and the excess phase with the extra 2.4 mSec delay. I stand by my original settings. Sort of. I just tweaked the woofers for smoother response and better left-to-right matching (measurements anyway....). But again, I'm listening to my own work with a heavy bias.

post-53989-1381968396194_thumb.jpg

Link to comment
Share on other sites

<snip> The bass boost that I mention was provided by a guy who has access to an anechoic chamber. <snip>

Chris

An anechoic chamber that's good to 31 Hz? I'm viewing this with a raised eyebrow... It must not be at an audio company. Automotive or aerospace, methinks

--Greg

Link to comment
Share on other sites

One of these days I might compile the DSP settings and post them. It's a lot of typing.

Really?

forums.klipsch.com/forums/p/143349/1465822.aspx

By the way, I believe that I live about 1 mile north-northeast of your residence (as a crow flies).

Cheers,

Chris

Awe geeze. I graduated from Martin High in 1987 and worked at the TGI Fridays and the Safari Bar, both by 6 Flags and the staduim, in the late 80's. I had a sweet mullet, a girlfriend with a big permanent hairdoo, JBL speakers and a 69 Camaro back then. Life was good.

My take on tri amping K Horns was that mine never sounded better. But, the real advantage was being able to adjust each driver individually. I was finally able to get them balanced and I was able to get rid of my subwoofer after tri amping. In the end it was too complicated and I wil use passive X-overs that can be adjusted in my next build.

Chris

Link to comment
Share on other sites

"It must not be at an audio company."

Telex took the 30hz one out of Turner Microphone and gave it to EV (I think).

"The Turner Company would not see 1980. It was picked clean by its new owners who kept the most profitable products and shut down all operations in Cedar Rapids. "

Link to comment
Share on other sites

Life is still good. Son just graduated (UTA in EE) and daughter graduated last year (TCU in Business) - and both have jobs now [:D][Y][<:o)]. Both graduated from Martin in the mid 2000s.

If you ever make it back to these parts, drop in for a listen. Bi-amping isn't too complicated. [:^)]

Chris

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...