For the past two week I wasn’t able to use my loudspeaker because of tweeter (Renaissance MST-33.5) malfunction.

I took the tweeter to a repair-shop and after several days in which they lost my tweeter and found it again, I was called to collect it. When I arrived I was told that the soft-dome was replaced since it was corrupted. I did noticed it was replaced since the previous dome was priced with a pin. (why it was pierced you ask? good question, one day about a month ago I noticed while I was listening to some music that the tweeter dome was pressed inside, I did not panic, and i gently released it using a safety pin).

I returned home filled with anticipation and for my (unfortunate) surprise the tweeter still did not work. I did not check the tweeter at the shop so I can’t complain, perhaps it wasn’t working when I collected it, any-ways - it’s my bad. I decided to investigate the problem my self, so I gently connected the speaker wires directly to the tweeter’s coil (white arrows) and found it functional!

Let the operation begin!

First, I removed the front aluminum plate

Removing the place reveled one disconnection in the coils wire (marked)

Removing the dome,

Taking out the coil with it’s base revealed a second disconnection:

To rewire, I stripped a speaker cable and rolled two thin threads out of it

Gently passing them from the connectors to the coil

Some delicate soldering to fix the first wire:

And i fixed the second one the same way, paying my attention that the two wires will be about the same length. Furthermore, I suspect that the reason of the malfunction in the first place was no slack, and therfore when I connected the tweeter to the speaker it might have cause the wire the tear. so I left about 2 mm slack just to be sure.

Finally, i tested the tweeter and found it ok

Then I clipped the remaining tips, assembled the tweeter back again

My guess is that this kind of malfunction was the reason it stopped working in the first place. I don’t hear any difference, I hope my fix was ok.

You can buy at newegg a brand-new mini-itx board with an onboard atom processor.

This board cost 75$ and it is a classic board for a digital filter, just plug a high-end sound card and there you go. a minimum cost low-power over-kill digital crossover with DRC capabilities.

It is about time we start seeing low-cost minit-itx combos.

Three days after assembling and testing my new loudspeakers I decided I was very displeased from the sound of them. I was very displeased in many ways, no micro details, no lively sound, the stage is awesome, so is the dynamic, but something was seriously wrong here. I have to clear one very important issue, all tests were made in a free-hearing-style, with no measuring equipment (it wasn’t necessary). The main problem I found was very heavy sound coloration. pressing my ear against the speaker while it play, i heard that the enclosure resonance very clearly, indeed something is seriously wrong. This weekend was dedicated to fixing this problem.

Whats on the menu?

1. Reinforcing the back panel.
2. Adding a separate chamber to the tweeter and high mid.
3. Stuffing the enclosure with rock-wool and snex.
4. fixing two holes (which were right-about 0.5mm too small).

Lets get to work!

Here are the pack-panel reinforcements

Here are some pictures of the construction of the tweeter + high mid chamber

Black RTV is very messy

Here are the speakers after adding the tweeter chamber and back-panel support reinforcements

Here is the back-panel covered with soundtec

Here is the finished result padded with Sonex and rock-wool (3 hours later and I’m still itchy)

Attaching the back-panel

And finally, connecting the drivers - this time with black screws

Construction comments:

1. Reinforcing the back panel - I used two 10×10x5cm hardwood blocks (on each speaker) to reduce the back-panel’s elastic freedom, attaching them was very easy and i hope they will do their job properly.
2. Adding a separate chamber to the tweeter and high mid - Using RTV was very natural since i had no easy way to apply pressure, so yellow-carpenters-glue was not a good option. other then getting myself completely covered with RTV the process went pretty well.
3. Stuffing the enclosure with rock-wool and snex - I acn only wish building a speaker was as easy as stuffing it.
4. fixing two holes (which were right-about 0.5mm too small) - Before I painted the speaker, I tested each hole and fixed them to the precise measure. apparently, due to the moisture of the paint or the paint itself, the radius of two of the holes became too small. I used sand-paper and very slowly sanded the hole. I aws afraid it would take 30 minutes but it only took 2-3. sanding finished wood is very scary. the thought of accidentally sanding a visible part is stressing, but it wall went well.

And now, after all of this hard work… how do they sound? Sorry, but I can’t answer this question. you’ll have to wait till next week. Seriously, There was a very unpleasing mis-fortunate accident to one of the tweeters, a few days ago i found it (still on the speaker) bent, the dome was pressed inside. i thought someone touched it… naturally I accused everyone around for messing with it. But, today when I turned on the power i notice it’s not working, and that leads me to suspect that the tweeter was a victom aof a violent DC current (which I also cannot tell how the hell that happened) that caused the dome to wised and perhaps the coil to burn. i will take it to my loudspeaker-repair man and hopefully it will return fixed. Nevertheless, i did manage to detect a very significant decrease in the enclosure resonance, however, it is not enough. Once my tweeter return from the shop I will study the resonance with more sophisticated tools then my ears. stay tuned.

TEXSA is a Spanish company that manufactures and markets products for roofing - waterproofing, thermal and acoustic insulation, as well as the corresponding auxiliary products for each of these fields. one of the products that TEXSA manufacture is called ‘tecsound’, and it is a rubber-like material, with  one stick side (make it very easy to use) that help to isolate/attenuate noises.

I decided to test this product based on a recommendation of yairf (here is one project in which he used the same material). The tecsound was bought at rotenberg, its not cheap and i hope it worth it. the specific gravity of the tecsound is 2kg/L, thats about as dense as concrete, 3 times more dense then the ply-wood used to build the speaker.

Here is the Rotenberg’s front display room

The construction material yard

The acoustic insulation shed (with my tecsound)

And finally, one role of tec sound (6×1m, 1.8mm thick role, weighting 21kg)

I sure hope this material can help me reduce some of the resonance in my enclosure.

I’m very excited because today I finished a project which started so many years ago (5 years ago I’ve posted my first desire) and had it’s twists and turns, but finally, I can proudly say I’m done.

After two days of hard work (soldering, drilling, hammering, heavy lifting and no sleep) I’m proud to present my new glorious hand-crafted quad-amplified speakers:

Every end is a new beginning, now that the speakers are constructed and finished, I can start a new interesting episode of tweaking: testing amplifiers, filters, sources, acoustic improvements, DRC and much more.

How do they sound? I am very pleased with the initial result. considering that nothing optimized and the way they sound now can only get better I’m convinced in the efforts and resources put into it were worth-while.

I have decided to upgrade! the new receiver, a dignified Denon 2807, will be dedicated to my ht setup, and after testing it with star-wars III (revised edition)  I can safely say it was a wise buy.

From top-down: (1) The new Denon 2807. (2) My 7″ touchscreen HTPC. (3) Harma-Kardon 5500
The Harman-Kardon 5500 will be assigned for the stereo mission. why do I need an ht receiver for stereo application? since my stereo speakers are quad amped, i’ll need 8 channels of amplification and some way to control the gain of all the amplifiers.  the hk-5500 will assist my to amplify 4 out of the 8 channels i need (2-fron and 2 rear channels) and I’ll feed the remaining 4 pre-out channels (center, sub-woofer and 2 rear surround) to two stereo amplifiers. this way i can use the hk-5500 as a gain control pre and as a 4 channel amplifier.  I hope I will be satisfied with the result, but I’ll elaborate more on this later-on.

Morel has posted a press release regarding a new loudspeaker, the fat lady.

FIY,  The price tag is ~20k.

Other then that, there are two  more happy news, the first is that the classic Octave series has been upgraded and the new loudspeakers are called Signature Octave, the second, is that the raw driver division now includes several new players, among them you can find a new Ultimate 12″ subwoofer with a 5″ coils (first in the world?) and several other interesting products which continue the line of high-end state of the art quality that we know.

I still find it hard to believe, after so much hard work, sleep-less nights, sacrifices and caffeine, my loudspeakers stand proud in my living room! I moved to this house more then a year ago, and one of my main concerns were where will i place my stereo. as it seems, there will be plenty of room for my new love ones. The pictures speak for themselves:

The back panel was treated with one coat of metal-primer to give it a nice “concrete” color, I hope it will fit the reddish-shad-maple veneer. other then that, I decided to mark the four terminals with a nice print, nothing fancy.

More pictures as soon as i mount the drivers. (can’t wait to hear them play)

This is the latest progress i made today.

BEFORE:

AFTER:

All holes were routed using a router guide I made once (very handy)

And some more poses:

The four drivers which are aligned on the surface of the speaker are: (a) a 10″ woofer; (b) a 6.5″ mid-woofer; (c) a 5.5″ high-mid and; (d) a 4.5″ tweeter. I’ve got barely 27.5″ for all four, leaving a margin of 0.25″ between each two drivers. Tight alignment as this is will contribute for time alignment (mostly for high frequencies), nevertheless, it’s harder to implement since even slight errors will be noticeable.