Hello and best regards to all readers of this website. After a long time of working and listening, I decided to place this project on the electrode. The project is interesting because I made many mistakes during its creation and it is a pity for me not to share these experiences with others. This project should be treated a bit as a warning / set of comments / experiences, and maybe even a warning against too rash taking action without prior substantive preparation.
Project - preparation and assumptions
At the beginning it was supposed to be a simple design, the only assumption of which was the width of the column: max 17/18 cm. This is due to the fact (as can be seen in the photos) that a wider column would block my exit to the balcony. From previous projects I had a few speakers on the basis of which I decided to build this set (ERROR 1 - randomly selected speakers) : and they were:
The housing was supposed to be closed with a capacity of 35l (and it remained so). the medium speaker chamber is about 4.5l. As the midrange and tweeter speakers coincided with the STX FX-200 set, I decided to commit too ERROR 2 - so I bought a dedicated crossover just for the STX FX-200 loudspeakers . Granite fronts and the side of the column were an additional assumption. The elements shown in the photos are made of real granite. I ordered them from an establishment that makes tombstones . The decision to use granite to build columns results from my love for natural and solid materials (it did not necessarily translate into sound quality - another small one [BUG]) ...
Armed with speakers, crossovers, boards and other materials, I decided to put it all together. The construction process was as shown in the photos below.
Version number 1 columns
After the construction was completed, the columns looked like this:
The loudspeakers looked like in the photos ... maybe even nice. Unfortunately, they played hopelessly. Their terrible sound was due to several things and the main reason for this was the placement of the woofer on the side, not using a sufficiently low division on the crossover [ERROR 3] . It wouldn't even be such a big problem if it wasn't for the fact that the midrange driver is only a mid-range speaker and not a midwoofer [ERROR 4] .
And what to do with it next?
Unfortunately, the ill-thought-out design has already been closed, assembled, soldered and glued .. There was no large room for maneuver and the advice of specialists was unambiguous (thank you again, colleague Tomq): post . I started to figure out and build my own crossover. I armed myself with the holmImpulse program, microphones, resistors, capacitors, wire and a room. The results of the measurements were, however, poor ... Poor because the graphs turned out to be perfect - just the perfect characteristics of the loudspeakers. Unfortunately, the ear did not allow you to believe what the eye saw on the chart So without going into further details of the measurements - because it already took me a lot of time and the speaker hobby began to take more and more of it, the prospects for a quick completion of the project were not optimistic and the lack of knowledge was still gigantic. Also, the costs incurred for the construction of the columns were not low and the granite fronts were hardly modifiable ... In such a situation, I only had to report to someone who knows more about the construction of columns than I do. So I searched the Internet for the nearest company that measures the columns. I found it, took the column away and waited for the verdict.
The new life of the project, i.e. version number 2
After taking measurements with appropriate equipment and in appropriate conditions, the verdict was as follows: "in a word, a massacre! Nice housing, but it will be difficult to do something about it" .... However, I managed to convince your specialist to do anything with it Such a tragedy ... He did not have much room for maneuver because the above-mentioned granite fronts did not allow for free exchange of transducers. The biggest problem was the mid-woofer, in the place of which it was necessary to insert a mid-woofer - unfortunately, the milling cutter made of granite significantly limited the possibilities of choosing something that has arms and legs ... After several days of searching, there was a speaker at a reasonable price and matching for carved holes. Is it FW-146 . The next step was to make a new crossover so that the woofer placed on the side of the loudspeaker would play 150Hz max and the other two began to harmonize with each other. After quite a long fight with my speakers, we managed to do something about the acoustic effect as shown in the pictures below:
Graphs / Measurements
Harmonic distortions A: impulse Waterfall The whole column
Apart from the new crossovers, the loudspeakers got new terminals, better soundproofing of the mid-woofer and additional soundproofing of the main chamber, as well as new cabling. And that's it ...
End of the project and conclusions
Ultimately, I made a decision that I would not assemble any more speakers myself (in the sense without the help of a specialist). This decision is made up of the following factors:
- I do not have sufficient skills and acquiring them requires a lot of time and practice. - I do not have a measuring base or sufficient knowledge to test the loudspeakers by myself. - The sound of the speakers after modification in comparison to my other works of art causes a quality gap.
Of course, the hobby will remain and there will certainly be a few more constructions. However, each subsequent construction will be better prepared and thoughtful. Finally, the columns look like in the pictures below:
I am generally satisfied with the loudspeakers, although their construction cost was 3 times more than it should have been. Granite fronts and 22mm plate were an exaggeration for the unnecessarily purchased STX crossovers, not to mention ... The sound of the loudspeakers is certainly better (at least for me) than in the case of the Altus copy, which I also own. It seems to me that the midrange is a bit lacking (maybe it's the fault of the aluminum diaphragm) - the speakers make up for it with the precision of the sound, which I like very much. However, I know that it can be better, which is why I am already preparing for the next project. I hope there will be a lot less errors this time :-)
Minor remarks for other designers:
1. OSB is not a bad material for building a column, unfortunately it is terribly inconvenient to work with. I chip off large pieces of the board that need to be repaired many times. Sanding the veneer at the edges is also not made easier. 2. Never stick cables to the sides of the housing. Even though everyone is writing about minimizing the length of the audio path, don't regret giving the cables 50cm of slack. Later, working on a closed column becomes a nightmare. Soldering the cables in the center of the column hurts (actually burns). 3. Making a column that weighs 40 kg is also not a good idea. Especially when you have to lift them later from the 4th floor by stairs There is no way to freely rearrange it in the apartment. 4. The time, work and dedication put into building the loudspeakers will not repay the sound quality if the electrical design sucks ...
I paid PLN 800 for the granite fronts. Holes cut with a water saw and cutters made by hand. I overpaid a bit because it could have been done smarter - without cutters and then it would have been cheaper.
If it's not a secret then I'd like to know the total cost. Since the fronts alone cost eight hundred zlotys, and you say that the price was three times higher than the assumptions, I see a few thousand speakers packed into them, (I mean this midwoofer, it completely does not match the rest). I would give black or other dark granite, but tastes are not discussed. However, it would be worth painting the edges of the cutters black, because at least in the photos, they are very noticeable. As for the sound, I can not listen to it, but the graphs are also not amazing, especially in relation to the costs. I agree with my friend that this whole construction is a MISTAKE, which is a pity, because the first photos immediately made me positive, especially these granites.
When deducting the cost of the parts that have not been used, it is about PLN 2,500. But adding microphones, unused speakers, crossover parts, fx-200 crossovers, etc., the budget exceeded 3k.
Below is the cost estimate before modifications:
I have not noted the modifications so meticulously I don't think I wanted to know the final price myself, although you can calculate it quite easily: 2x Fountek FW146 + crossovers / measurements / transport = about 1000 PLN. Also, taking the value from the calculation minus unused materials + 1000 this will be the final price. I must admit that I have a lot of veneer, glue and screws left, which I used for other things.
And I've already sold the FX-200 crossovers ...
The cutters are actually not nice in the photos, fortunately, in normal light it is not so visible.
It is a pity that the end result is not proportional to the costs and time spent, but I read the topic with curiosity. Maybe a few young designers will find out how important it is to rethink the project.
Whole speakers are quite large. With the stands their height is about 140 cm. Width 17cm, depth 33cm.
The exact dimensions of the elements here:
Below (attachments) are the exact designs of granite fronts. However, the designs show mounting holes, which unfortunately could not be made and finally the fronts were glued with a special stone glue.
Another mistake is the OSB board, which is the worst choice in the construction of columns. Here, I would use 12mm plywood with a few reinforcements inside the column.
I have to disagree with this statement. According to me and the information that I obtained while following various forums and sources about the materials for the construction of columns, I can say that plywood is acoustically inferior to OSB. The best is MDF, then chipboard / OSB and finally plywood.
If I am wrong, I am asking for a reliable source of information on this subject.
Plywood worse than OSB? You don't even know what you are writing. Plywood gives the best structural strength and is the best acoustically. Many leading companies make cases from this material. Plywood is the best.
Hardwood plywood is the best material for building columns, at least for me.
Then I think that OSB is good because it is hard and resistant to moisture and cheap, the disadvantages include its brittleness and difficulty in processing (especially cutting at an angle).
And the easiest way to process chipboard and MDF, but they have their drawbacks.
The loudspeakers turned out nice, personally I do not like loudspeakers with woofers on the side.
Is this granite the same as used in tombstones? At least that's what I see in the photos. He is quite hard and brittle. Does such a graphite front have any acoustic properties or do they only play a decorative role?
Col. arek59 is granite, not graphite. The OSB board takes the last place in choosing the material for the casing. If a colleague had used 12 mm plywood, the column would have been lighter. 40 kilos for such speakers is definitely too much. This granite slab is not a lightweight one. One column should weigh a maximum of 20-25 kilos.
I don't believe it - marble as an element of the column housing. Interesting. But when you spent so much money on such material, you could have used a better material for the housing. Marble and OSB - it's like buying a Mercedes for 200,000. PLN and put on gas to it. OSB should crumble less and split when cut with an electric saw (high speed). A lot of work has been done, it is a fact. And funds, but I have never liked such innovative, exuberant structures. For me, the beauty of the loudspeakers lies in their simplicity - ordinary, normal boxes, without any decorations.
I have to disagree with this statement. According to me and the information that I got from following various forums ...
So you've come to the wrong forum. OSB is the worst material for columns. Plywood and MDF are the best materials for loudspeakers, and these materials are used by companies such as Sonus Faber.
If a colleague had used 12 mm plywood, the column would have been lighter. 40 kilos for such speakers is definitely too much. One column should weigh a maximum of 20-25 kilos.
Where did you get the information that a given column should weigh 20-25kg? After all, everyone knows that the heavier the loudspeaker, the better acoustically, the only drawback is the problem with moving ... but who bothers? Home speakers are supposed to sound well, it's not the PA to go somewhere with it every day. Besides, replacing the OSB with plywood (and the 12mm is simply stupid, because the 12mm would only be suitable for monitors with a 4 "woofer), you will not suddenly go down from 40kg to 25kg, which would only be a few kilos less.
The loudspeakers look unusual, I like them (visually, because the bass on the side does not suit me acoustically). The most important thing is that the owner is aware of the mistakes made (and the price kills ... for it you could assemble the loudspeakers on the Scan Speak speakers and not think about changing to others for many years), the next design will be more thoughtful. I have the Fountek FW146 in monitors that I have recently made, for this price it is difficult to find a competitor.
I admit that when it comes to the amount spent, it is a great failure. On the other hand, what I really like - despite everything, my colleague is soberly reporting all stages of construction without any "sentiments". I am full of appreciation. The lesson is, it's just a pity that it's so expensive. It's good that there was a person / company in all of this who helped with the final touch. When it comes to converters, there is no tragedy (now). The colleague drew the correct conclusions. So I wish you successful further constructions. I have never done this before, but I gave a colleague from my pool of 500 points. Comfort? Not. Thanks for sharing your insights. I also allowed myself to "stick" the topic as an article.
Congratulations on the idea, or rather the vision and self-denial Also, admit your mistakes to yourself. However, among the mass of posts I missed one very important thing and information for others as well, namely : We should never try to force the loudspeakers somewhere, because we have 20 cm, so I will buy a 19 cm wide column. This is a big mistake the column must breathe to have a certain distance from the back and side walls. The column by the glass is also a big mistake, the lack of curtains and the stone floor does not help either. It is not even about bas-reflexes, etc., but creating space. The best column squeezed between the side wall and the sofa or a gap in the segment will sound like trash for PLN 200. You push the floor column somewhere like a sausage into a roll, buy better stand-mount monitors and even put it on a chest of drawers.
Indeed, the arrangement of the columns is not optimal, but it will change with the development of the entire project. And the goal is 5.1. Now I have started working on another pair of speakers (I am trying to eliminate all the mistakes I made earlier). This time the speakers for the MTB system will go under the hammer: