DIY Boombox in a suitcase!

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Hello!

I am currently doing TONS of research on a DIY project I wish to be making real soon.

My goal is to make a mono boombox into a suitcase, something like this http://store.theboomcase.com/tweedly-deedly

I have been looking into many different woofers, midranges, tweeters and I have come to some conclusions. I am going 3 way ofc, although I am on a quite low budget so I prefer buying most components inside Sweden from stores like hifikit. However, this is the setup I am currently looking at:

Woofer : Peerless HDS Nomex 830869 8"
Midrange : Peerless HDS Nomex 832873 5"
Tweeter : Seas Prestige 27TBFC/G OR Vifa D26NC55-06
Amplifier : AMP11 by 41hz.com


Now my question is:

Which tweeter should I choose?
How should I make a valid crossover for them?
Will this 3-way work good in a sealed enclosure?
What is YOUR impressions on this in overall?
 
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This woofer is totally unsuitable for a sealed box. The project seems to me like something that will only lead to disappointment and I'm not being just negative, it's something I'd rather prevent you from since (I know from experiments I've done as a newbie in the past) it spoils a lot of the fun.

Sealed boxes usually need Qts value that is rather a bit higher than 0.4 preferrably.

Go and install some freeware box calculator like AJsealed and fill in the specs and see what it simulates like....

Then AMP11 is a fine amplifier for such a project, you just need to aim for 4 ohm speakers or paralleled 8 ohm to get the max out of it since it is an amplifier that delivers quite a bit of current.

To get loud you can go two ways, use the current by using enough load to it or use the voltage by a speaker that can handle it. The better speaker is always the one that provides max efficiency at the SAME wattage (Usually 1 watt measured at 1 meter, beware for false manufacturers specs like 2.83V at 4 ohms, which is effectively 2 watts!!) And has good linearity, wide band response, no break ups and a wide radiation pattern.

Manufacturers love to sacrifice the one to get the other spec up to the roof, just to have good sales. Like a horn loaded speaker has excellent efficiency, but at sacrificed dispersion.

Speaker selection is therefore best left to pros in the field, but one should start the learning curve somewhere....

If you want good results cheap and simple you are lucky to start by going for a sealed enclosure. They actually work great with a multitude of cheap speakers. I'd not start with a three way also if I were you. Getting these 'right' is a pure art and a very rare kind too! If it is at all feasible...

Maybe the best thing to do is copy a thing or two from a well know and good working design and go from there....
 
DIY HT Design Sealed vs Ported Repoll - Page 2 - AVS Forum

Some audiophiles over at that forum explained that the Peerless HDS 830869 was meant to be used in a sealed enclosure. You still think its a bad woofer for this project?

I been doing so much research that I think I have lost my mind into this mess, I really cant figure out which speakers to use... I want 8 or 10" woofer, not 2 just 1... And I am not buying some junk cus that would just leave me unsatisfied. I am born for good sound!

Thanks nonetheless for explaining the deal with 4 ohm amplifier, maybe buying the amp6 and connecting each channel to one driver is a better choice. That way I would only need to buy 1 battery. If that now works?

Anyone who perhaps could point me to some valid speakers incase these are bad? :)
 
Seas Prestige A26RE4 also seems very interesting!

Seems to be equall to the old legendary Syndaco A-25 woofer!

Seas Prestige A26RE4 (H1411) 10" Paper Cone: Madisound Speaker Store

"This classic paper cone has a wonderful roll off at 2000Hz. This is one of the only 10" drivers we know of that could be used in a 2-way by letting the woofer run full range without a crossover. I have heard this woofer with the Seas 27TDFC (H1189) tweeter and it had a magical retro sound to it."

How does that sound? Maybe that could be a great candidate for a portable sealed boombox! I would also get rid of the hazzle of 3 way crossovers...

Not to mention the AWESOME look it has, its like meant to be used with a blue vintage suitcase! Haha :D BUUUUUUT I guess my dreams will once again be crushed by finding out that its not suitable! FML
 
If you give some more specifications for the project , the following answers would be narrowed ...
Such as : environment :eek: like where the box is going to play , position , audience ,open space , room ,near boundaries , etc.
Approximately how big (max and min ) it would be , and what weight ( wheels :p ?? )
From what I have understood , you want approximately a 100 W single box , which would incorporate wf ,mid and tw , a mono amp , a 3 way passive crossover and the battery .
My thougths tell me that an 8 or 10 " wf produce a lot of pressure , so what kind of material for the enclosure / suitcase are you interested in using ?
I've done some ( two :eek: ) with plastic ( polycarbonate ,3-4 mm ) with some lead foils in the 'danger zones' , medium stuffing ,max wf diameter was a 7" ,but the bigger box
was with a 5" ! Biamped with a stereo 10+10 w chip amp
and passive 1st order .
I took a look at the website in your country , and it has also nice things in the Pro (PA) section . The drivers cost more , but they deliver more power with the same Watts at input .
 
My wish would be to use a suitcase ranging from 21" (21x14x7") to 24" (24x18x7") in size. Which equalls to a volume of 32L and 47L. Because of weight I have been considering going mono, that way I would only have to buy one set of speakers and not 2. If you read my #7 post I also pointed out another very interesting candidate. 2 way with Seas Speakers. I also know for a fact that the suitcases dont have the most solid material but that could easly be fixed, so lets not worry about that. My plan is to have a portable speaker that I could bring with me to friends place, sometimes playing outsides infront of a small group of people (10 people MAX) or just in my very small room of 12sqm. So being able to play really LOUD isnt the main concern which is why I think a sensitivity of 89db/1W is good enought. I have also looked up some Pro speakers but I think they lack in producing low frequences with detailed bass! And I think going with smaller speakers wouldnt be as much fun, I mean... 10"! Smaller element wouldnt give the same sensible feeling nor would it look as cool!

btw, I am very pleased with any help or feedback considering this project!
 
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