Recommendation of 8-Inch Woofer + Real Tweeter

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When you can get an extra octave more extension going vented, I would advise not shrinking your box smaller. Using an 8" to 66Hz as the lowest seems like a waste to me.

Later,
Wolf

I would like some "analogy" on how the techs of what you say is, so it would be easier to understand and see this.

I thought of going vented with my current drivers, since it matches their datasheet.
 
Ok, so I have the exact size of my current box.
Not having to do anything to it, apart from adding port or re-lacquering/painting would be the ideal thing for this project.

The measurements from within, discounting the ply are: (I will do it in centimeters because I can't interpret well the inch system without major maths in here :) ).

Height = 50cm
Length = 29,9cm
Depth = 22cm

That gives a 32,89 Liters box. Minus 1 Liter of driver displacement: 31,89. This is REAL CLOSE to the Dayton specs for a vented box. I don't know if I could get away with it. Could I possibly do?

Another thought would be to get the front ply and move inwards about 5 cm (down to 25 L), which would not be enough for a sealed box, with this Dayton woofer.

The Dayton woofer is really on a budget in Canada, being HALF of the american price. Someone needs to fill me in why this is like that (Health care system kinda analogy related here? :) )

So I could buy these two Dayton, two Dayton dome tweeters (RC28F-8) and design a crossover after the parts arrive home... for sure I'd get the air core inductors with the purchase because the guy I know only work with 17 AWG and charges an eyeball for it.
 
Perfect. It just needs a long port (50cm) for the 30L in the reflex enclosure that can be adjusted later. Nice driver on paper.
2-way, using Dayton Audio RS225-8 woofer and RS28F tweeter:
RS duet by Paul Kittinger

Sorry to be a nag, but that vent doesn't sound remotely right to me. I'd be looking at 50-60mm diameter and about 10 cm. long. Adjustable tubes are quite useful with this sort of thing. You glue or duck tape them solid when they are about right. :)
 
I will use a seas prestige 8 inch woofer. With a classic 6.5 vifa thats known to be very smooth in the mid range. I have some very good sounding full sized sealed boxes that accept 8s I will first try the seas in. On paper they look like they will work in a sealed speaker. If they dont line up I might be able to use them as another reference to gauge new dimensions.
 
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Sorry to be a nag, but that vent doesn't sound remotely right to me. I'd be looking at 50-60mm diameter and about 10 cm. long. Adjustable tubes are quite useful with this sort of thing. You glue or duck tape them solid when they are about right. :)
You are a nag... :D
I was mentioning the port so that the OP is aware that will reduce internal volume.
A speaker that is larger (volume) will have a shorter port. In this case a smaller than optimal 30 L the port (~2/3 L) will play a significant roll in the alignment of the speaker and it's internal dimensions. It's logical, if you reduce the diameter of the port you will end with a shorter port and higher air speed for the same RMS power.

If you guys make mention of a port (size/dimensions) please make sure to post the size (volume) of the enclosure (and diameter/length of the port or tunning frequency) so that we always have a small idea of the alignment that is being talked about. The port of the speaker that is posted in my link is for a big volume floorstander speaker, so the alignment makes a big difference to the one of the OP's, with it's 5" port.
 
This is actually being quite fun. I will buy new egg shell pads to the box and I will also construct a port so that I can use with this drivers I have.

Can I build a port that will handle the Dayton in the future, but at the same time, be used with the currenct Hinor driver?

Turns out that I will have to plan better for the Daytons. The average US price is around US$ 55. All the drivers and tweeters would cost me something like $ 222.00. The problem is that I will have to cope with 60% of taxes that Customs will happily apply. The international freight I suppose it will be around $ 100.00. For taxes, even the freight is counted as value. The whole thing reaches almost 1K BRL, so there the cost-benefit starts to be overwhelming ...
 
WinISD simulations on vented and sealed box:
(Strange that the values are way up than the manufacturer's).

I am observing that with the vented box, properly ajusted to 31 L, there is a little bump on the curve within range 70 - 200 Hz.


daytonvented1397528544.jpg


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dayton3a1397528941.jpg


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With sealed, the default recommended enclosure is 27.5 Liters.
I changed to 31. The ascension curve had a tiny slight change, very insignificant, going backwards. The two here:

daytonclosed1397528555.jpg


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daytonclosed3b1397529349.jpg



I know this is only a simulation. Why does the manufacturer specifies 12,5 L for sealed and 33 L for vented ? Could WinISD be wrong?
 
Selenium, PRV Audio, Bravox, Matador by JBL SELENIUM

This is actually being quite fun. I will buy new egg shell pads to the box and I will also construct a port so that I can use with this drivers I have.

Can I build a port that will handle the Dayton in the future, but at the same time, be used with the currenct Hinor driver?

Turns out that I will have to plan better for the Daytons. The average US price is around US$ 55. All the drivers and tweeters would cost me something like $ 222.00. The problem is that I will have to cope with 60% of taxes that Customs will happily apply. The international freight I suppose it will be around $ 100.00. For taxes, even the freight is counted as value. The whole thing reaches almost 1K BRL, so there the cost-benefit starts to be overwhelming ...
Taxes are a PITA. :headbash:
I understand...

Ports: you don't need to save ports from one project to future projects, because that's what they are a future project with a new port that after cutting and gluing is difficult to remove. You can save them, but, in six months or one year after starting in diyAudio forums you will end up with futur'istic ports that will serve you in the future. You can find them everywhere. Around your house (or block, inside/outside), in or close to the office, when there are repairs or building works going on, also street works like for cables or other, after decorations, where graphics arts reside or engineers or architects (services); all this people work with paper or plastic/ABS type tubes for ground work or for their XEROX/HPs production printers & copiers. You will find that saving is not needed when you start hoarding them.

For now, I agree with you, concentrate in the driver(s) you have at ends.

Try to get a way of measuring them for all your future projects. You can also offer a new service to the population (speaker or driver measurement services) for a couple of bucks. You will have to concentrate in the T/S parameters to design new enclosure/speakers, and if possible in a second phase to measure the output/phase/impedance in frequency. Then you can use any "mistery" driver for any manufacturer in Brasil, documented or not.

I'm going to give you another address (for car audio) in Brasil, where maybe and after spending some time, you or us can find some good "home-oriented-drivers", this with some luck, below.

For future reference, you just have to mention the design type you are looking for 2-way (other), reflex, sealed (other) and the internal volume (net/L), plus the Brasil link or links you are looking@, more PRV Audio - Brazil (en). Bravox - Brazil, JBL SELENIUM

E.G. (these are all drivers you can find in your country):
1.
Selenium 6W4P
Alto falantes Mid Bass, Mid Range, Médio-grave... Dicas de Uso - YouTube
6" good for open baffle type speaker (OB)
2.
Selenium WPU1205
12" good in a 30 L reflex.
3.
Selenium 12PW5
12" for a 50 L reflex.
4.
SNAKE ESV 620-W, VB = 40 L reflex or TL/quarter wave type.

Obvious these are not the type of woofers/subwoofers drivers that have LF extension to sub 20Hz region. For that, you need other type of driver and spend your time looking. I know that other members in the forum have used the Bravox for that, but... you don't want us to take the fun out of your quest or do you??? ;)
 
Inductor,

Thanks a lot for your tips. I guess I could make a real effort to get those Daytons (woofers only) part by part. There are no taxes if purchase is up to US$ 100.00. I would just take care of the cross-over woofer part and still keep the piezo part separetly. I am quoting with Meniscus and I will post tomorrow the shipping costs. Will be interesting to see.

The only thing that I need to pay attention upon this purchase is to get, ahead of time, the right air core cross-overs and components for the woofer crossover part only.

I say this because, I don't have identical current drivers. One is 8HTS500, and other is a bit older, 8HTS400. They are not the same, but they sound similar. I think that the port build with overall new lacquering and new foams would go really well with new woofers and I can just maintain the expensive Dayton tweeters for later the year.

Did you guys came to a conclusion about which is the right port for Dayton RS225-8 on a 30L box? 7.5 cm wide and 10 cm long ? Follow the WinISD exact values?

This is fun because the options are so many. You can spend your bank account on every single part, or you can do a project and carry on by stages.

It amazes me that in Portugal they do those taxes as well? Are these taxes similar to what we have here? We do have good and competitive products in here but certain things like loudspeakers, it can be as expensive as importation - folks in here just don't give a damn.

Anyway, this is fun, every day you learn a bit more and get more familiar with it. It's like Java. It takes a while for you to understand what certain things really do.
 
There are no taxes if purchase is up to US$ 100.00.
Hey, ok.
They had a similar arrangement here before joining the stupid euro. Now everything from the euro zone pays IVA/VAT (Value added tax) only that here it is 23%. (I guess if it is from China it pays 0%) From overseas, in general, it is more it's obvious. Maybe you could get someone friend/family abroad sending it to you as a gift. I used to do that from the US, for Christmas. :snowman:
 
Dayton RS225-8

WinISD simulations on vented and sealed box:
(Strange that the values are way up than the manufacturer's).

I am observing that with the vented box, properly ajusted to 31 L, there is a little bump on the curve within range 70 - 200 Hz.
Yes, that would be a typical 2-way arrangement. Let's say a 28L@29Hz, if you make the space for the port..
With the crossover, BSC and enclosure you don't see that as a bump but a smooth line in output, until rolloff at LF. Model and measure. :)
 
Dayton RS225-8

I know this is only a simulation. Why does the manufacturer specifies 12,5 L for sealed and 33 L for vented ? Could WinISD be wrong?
Take that as a precaution. They might be wright, when that's the right person doing it. Sometimes is an alignment for car audio, totally off.
So, don't believe them as a general rule. You are superior, with the right tools in hand. And always ask the question you need to ask if you call.

There was this guy that called Beyma in SPAIN. (This past week, in another thread of diyAudio). They replied that they forgot, after a changing in the manufacture of a 10" driver to substitute the previous pdf by a new one with new T/S parameters specs and measurements.

An alignment is always different from something else, if you have a different purpose for it.

A typical alignment for Dayton RS225-8 (not a 2-way as I mentioned, or it can be) is in a 38 L reflex. That driver likes generous enclosures, as you can see from my link to the project above (post#26), so there's no sense in squeezing it in tinny little boxes unless you have a project like that at hands. You mentioned the bump but when doing a 2-way, if you take the tweeter and crossover out and leave the woofer and the enclosure only, usually it looks like that, with a small damped enclosure and a high Q.
 
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