Big Speaker Project, 18” + 10” + CD/horn, super tweeter

Any update about the sound

Thanks for the question!

I have been letting them run about 8 hours a day for the past 11 days, so a few more to go to get to 100 hours. Different music, different days, mostly mid volume, with a few hours at 100 dB rap thrown in!

I have purposely refrained from “really” listening until they are at 100 hours.

I have yet to finalize adjustments on the Hypex (yes, running the Hypex for the 18’s), haven’t even set the gain, just running on Troels’s settings.

I also installed an attenuator for the compression driver, I have left it centered.

For the mids and highs I’m running the Babelfish J’s I built. I also want to try out the KT 150 amps I built soon too.

Of course you can’t actually even passively listen without some impressions right?

The sweet spot is a good 2-3 seats wide. I have been caught a couple times looking for an unexpected sound coming from a good 2-3 feet past the speaker. Low to mid low volume still has dynamics and detail, very happy with that.

Only negative I’m hearing so far is at higher volume. At mid volume everything seems effortless, at high volume seems strained. My amps put out +100wpc all class A, so not sure it could be the amps?
 
Once you start listening properly and measurements are obtained things can then be deciphered,

When you express concern of sound at higher volume have you used a spl meter to see how loud it is, a powerful clean sounding system can be very high in spl without realising what it’s pumping out:D it’s effortless :wiz:

I was shocked once when I went outside in the garden with the doors n windows closed and thought bloody hell it don’t sound that loud inside:scared:

Something do to with relevant distortion and how the brain interpretates loudness I believe

Well done on a cracking build project
 
Thanks beardman, ErnieM, and charlie2 for taking the time to comment!

I’m within a couple hours now of 100. So before I replied I played around a little.

To loosen things up a little I played Jem, They and Phaeleh, Fallen Light. Good, solid, quick, bass. Decimal meters bouncing to a high of 111 dB, 500 watt Hypex blinking red at me. I think my ears are bleeding.

Then at a high of 85d dB I listed to Josefine Cronholm, In your Wild Garden and My Room. Harshness gone.

Now enjoying a little Bossa Nova Music Specialists before I watch the next episode of Most Beautiful Thing on Netflix.

It seems I enjoy listening at high of 85 dB.

Comments welcome!
 
Maybe i see the your problem with this....500 watt Hypex blinking red...

what about the amp for upper unit,,,is it close to max....and therefor sound a little bad

those speaker can take a lot of Watt....and do it with low distortion

so something tell me ...your amp is maybe not big enough to play so loud...and 111db is loud.....can the spl meter measure the dynamic db----maybe the dynamic db is much higher...

A friend of mine have a big speaker system with SB unit,,,,he use 3 PA amp with massive watt ...sensitivity around 92db for the speaker
i have seen the amp blink red,,,loud yes,,,but it also tell that the last db shall use a lot of watt

i have over 500w ,,,have never need more watt (have also tried with 200w from a Holton amp ..just fine and sound good to )

if you look at the impedance for the 18" with passive filter ,you will se it goes down to 3ohm around 120hz...not all amp like this (this is not the problem when you use it without passive ,but with the Hypex)

hope this help a little
 
Maybe i see the your problem with this....500 watt Hypex blinking red...

what about the amp for upper unit,,,is it close to max....and therefor sound a little bad

those speaker can take a lot of Watt....and do it with low distortion

so something tell me ...your amp is maybe not big enough to play so loud...and 111db is loud.....can the spl meter measure the dynamic db----maybe the dynamic db is much higher...

A friend of mine have a big speaker system with SB unit,,,,he use 3 PA amp with massive watt ...sensitivity around 92db for the speaker
i have seen the amp blink red,,,loud yes,,,but it also tell that the last db shall use a lot of watt

i have over 500w ,,,have never need more watt (have also tried with 200w from a Holton amp ..just fine and sound good to )

if you look at the impedance for the 18" with passive filter ,you will se it goes down to 3ohm around 120hz...not all amp like this (this is not the problem when you use it without passive ,but with the Hypex)

hope this help a little

Thanks for posting and comments along my journey!

I’m just passing 100 hours, and I can still hear some small changes. Been sidetracked lately swapping an LS3/6L80 into my 1969 Mercedes, so enjoying listening when I can.

Soon I will be starting to adjust the compression driver, the Hypex, and even swap over to my KT150 amps for fun.

No problem with the Hypex blinking red, I was just seeing how loud a dB reading I could get out of these speakers at max volume. Way uncomfortable for my ears anything over 100db.

But I’m am very happy with the speakers.
 
I have also tried to adjust the compression driver ,,but i prefer the value from troels g.

what is it for a KT150 amp you have ?

just listening to Beth Hart live at the royal albert hall on DVD.. sound really nice,,very lively
try to move around in the room and hear how the sound still remain very big..filling the room...must be because of the big unit in the speaker..

Best bjarne
 
I have also tried to adjust the compression driver ,,but i prefer the value from troels g.

what is it for a KT150 amp you have ?

just listening to Beth Hart live at the royal albert hall on DVD.. sound really nice,,very lively
try to move around in the room and hear how the sound still remain very big..filling the room...must be because of the big unit in the speaker..

Best bjarne

Thanks much for the back and forth!

So about adjusting the compression driver. I installed Troels L-pad option. Purchased a pair from Fostex.

Today I spent about half the day playing audio. Since I’m over the 100 hour mark, I played with toe-in, adjusting the compression driver, and minimal adjustments on the Hypex, really only the volume.

Seems I get the the best soundstage with the baffles toed in slightly, pointed to the imaginary people on my right and left, respectively.

Volume about 50% on the Hypex.

And not sure what adjusting the L-pad on the compression driver is supposed to change. But this adjustment was the most beneficial of the day. At its most lowest setting the treble seemed muddy, at its highest setting is sounded clinical. It seems I’m happiest at about 3/4 of the way toward highest setting.

I have to say I’m really surprised at how much difference this adjustment can make.

This corrected the discomfort I was feeling at higher volume.

I downloaded a couple of audiophile albums today to check them out. Chasing the Dragon, albums 1 and 2. On album 1, track 1, Concerto for 2 Mandolins by Vivaldi, I would swear that one of the mandolins was be plucked completely to my right side.

Really getting excited about these speakers now. Just amazing full sound.

And I agree with you on the sound quality all around the room. You really don’t feel like you need to have your head in a vise to enjoy!

Here is a pic of my KT150 amps I built, circuitry and boards by K & K Audio. Looking forward to trying them out on these speakers. Probably wait a couple weeks to fully get used to my Babelfish J’s.

3DCC87E4-976C-4BF5-99CE-704658BA3E82.jpeg
 
Hi
i think you discover the same thing in those speaker ,as i have..

i remember you use PathAudio Resistors i must try those..but a little expensive for now

will be good to hear what the tube amp can do...I heard Troels G- Glowmaster tube amp when i was in his place to hear the Loudspeaker...very good sounding amp

you have some really fine gear to use with your speaker,,,

Best Bjarne
 

ICG

Disabled Account
Joined 2007
Everything is mounted to the board with hot glue and silicone, heavy items I also added zip-ties.

You used hot glue and silicone? The resistors get hot. Really, they get HOT hot. While hot glue melts at ~170-200°, it becomes softer and gooey and loses adhesion with low force (gravity i.e.) before that. Silicone holds up better but is a better thermal insulator and the surface contact molecules age rapidly and breaking apart earlier which means they lose the ability to hold the resistors in place.
That means, you need to secure the resistors mechanically because they can dangle and shorten other crossover parts or burn capacitors.
 

ICG

Disabled Account
Joined 2007
is it all the resistor that get hot.....are this in the Loudspeaker you mean

i have not think about that ...must measure to find out

The coils might get a warm with high power but that's no problem if the dimensions are adequate. If they are too small they could get hot too but they look fine to me. The capacitors have next to nothing warmth dissipation. The L-Pad (basically a resistor too) can get warm or even hot.

E: Zip-ties are also not heat resistant.
 
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I wanted to build JBL 43xx clones for a long time. When the realization that original drivers were getting scarce and expensive, alternatives became realistic choices.

I think the game changers for a modern LARGE REFERENCE SPEAKER are the coaxial compression drivers, modern profile 24" - 30" wide horns, and multi-amp DSP. $2000-each + cabinets

There have been a couple discussion threads on controlled directivity and room integration. Experiments of when and how a horn's controlled directivity should transfer into a full room polar response will define the NEW LARGE REFERENCE SPEAKER .

coaxial compression drivers which perform well down to 500Hz
2" BMS 4594ND, 1.4" BMS 4592HE, 1.4" B&C DCX464

modern profile 24" - 30" horns which perform well down to 500Hz ... even 300Hz:
SEOS24, SEOS30, eJMLC300, Klipsch K501, JBL-M2, JBL-2384
 

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Hi
i think you discover the same thing in those speaker ,as i have..

i remember you use PathAudio Resistors i must try those..but a little expensive for now

will be good to hear what the tube amp can do...I heard Troels G- Glowmaster tube amp when i was in his place to hear the Loudspeaker...very good sounding amp

you have some really fine gear to use with your speaker,,,

Best Bjarne

Thanks for the compliment on gear! Play toys.

I had some communication with Troels about adjusting the L-pad/compression driver. He said where I settled on, 1.5 dB (on the Fostex L-pad dial face) is about the same as what he has as the fixed resistor. So looks like my ears are close!
 
You used hot glue and silicone? The resistors get hot. Really, they get HOT hot. While hot glue melts at ~170-200°, it becomes softer and gooey and loses adhesion with low force (gravity i.e.) before that. Silicone holds up better but is a better thermal insulator and the surface contact molecules age rapidly and breaking apart earlier which means they lose the ability to hold the resistors in place.
That means, you need to secure the resistors mechanically because they can dangle and shorten other crossover parts or burn capacitors.

I had never read about an alternative to silicone or hot glue or tie wraps for fixing the components.

Hot glue was used to hold the components in place until the silicone has time to dry, so I can keep on working.

All three were used on the coils. The zip ties to make sure, due to their weight, that nothing moves.

I also have a feeling that the hot glue/silicone adds some dampening.

So I took to heart your comments and spent some time today researching and measuring.

The data sheet for the hot glue used says the softening point is 206 degrees

The data sheet for the silicone used is rated to 250 degrees

The data sheet for the zip ties says they are rated to 185 degrees

I used my infrared thermometer to measure the caps, resistors, coils and even the Hypex.

The benchmark for testing; the speakers have been running for 9 hours at normal listening levels, the weather channel shows current temperature (5:00 pm) at 76 degrees. Windows open, slight breeze (19 mph), sunny.

All measurements taken with an infrared thermometer;

The cabinet measured 79 degrees and gives a good benchmark for the room temperature and the thermometer

The resistors were all close to the same, high of 87 degrees

The coils were all close to the same, high of 87 degrees

The body of the L-pad measured 83 degrees

The hottest point on the Hypex measured 113 degrees.

I have a common pocket behind the two panels and the Hypex. This was by design to give the Hypex more room to dissipate its generated heat. I have a feeling that some of that heat has warmed up the other components. The L-pad is physically connected to the aluminum cover, and I think it acts as a heatsink as to the reason it’s a little cooler.

But even with the Hypex generating a lot of heat the speaker is still running at about 50% below the fasteners specs.

What do you think?

C5AF8FE1-24E4-4846-A91F-07DA6949C090.jpeg
 

ICG

Disabled Account
Joined 2007
I assume you're talking about °F.

I assume you live in the USA and you're still in spring.

The temperatures you've measured (if my assumptions so far are correct) are therefore with an ambient temperature of around 26°C/79°F. If you're at 79°F ambient temperature, the temperatures of the parts are not critical in any way. The 9hrs use do not say much. Well, the temperature of the parts isn't absolute, they are ambient temperature + the heat they generate. If you've got an ambient temperature higher than you do now, the parts temperature rises the same. And then the power used contributes a lot to the parts temperature too, so a listening session with 6dB more already quadruples the power used and your speaker is capable of a lot more. A speaker demonstration to friends or a summer party could easily add a lot more, I've seen a lot of burnt crossovers and self-desoldering resistors, drops of solder dropping somewhere, despite the owners saying 'that was NEVER a problem, why now?'. So it's maybe completely fine but you have to make the call for yourself if 'maybe' is safe enough.
 
Any update on sound from the speaker

My real job (to make a living) has its busy and slow times. The last week or so has been a busy time, so no time for play, audio or automotive.

Prior I had been running the speakers a good 8 hours a day every day for about 13 days straight while I was around the house, to get them broken in.

Today was the first time I had a bit of time to relax and listen to music. I swear they sounded better today than they did a week ago. Maybe after they had a rest!

Mostly streaming Tidal, but then I pulled out some vinyl for the first time on these speakers, Daft Punk Random Access Memories, and had some fun. So dynamic! Just crazy how much more information coming through that I didn’t remember from prior listening.

Having a fun journey, thanks for asking!