First 2-way project

hello guyz,

I finished my LM3886 amp which delivers [email protected] per channel(22v,250va tranformer).

Now, its time to begin building the speakers. After long searching i decided to use peerless woofer and hivi SD1.1-A tweeter(15watt).

I concluded in 2 peerless woofers:

Peerless 830875 6-1/2" Nomex Cone HDS Woofer | Parts-Express.com (50 watt)

and

Peerless 830860 5-1/4" PPB Cone HDS Woofer | Parts-Express.com (30watt)

I like most the first option(50watt) but how will my amplifier(whitch is 40watt/channel @8ohms) go with this option?

It is ok to drive 50watt woofer with a 40watt amp? Or i have to go with the 30watt woofer?
 
Hi,

Though your drivers are decent choices its best to use the
hard work done by other people for your first louspeaker build.
See the first few links. Powerhandling issues are more complicated
that you think but nearly all designs will be fine with 40W / channel.

rgds, sreten.

Paul Carmody's DIY Audio Projects - undefinition
Zaph|Audio
FRD Consortium tools guide
RJB Audio Projects
Speaker Design Works
HTGuide Forum - A Guide to HTguide.com Completed Speaker Designs.
Humble Homemade Hifi
Click below to go to
Quarter Wavelength Loudspeaker Design
The Frugal-Horns Site -- High Performance, Low Cost DIY Horn Designs
Linkwitz Lab - Loudspeaker Design
Music and Design
 
thanks for the links man.

I would like to build the project by my own. Peerless are fairly easy speakers for
crossovers i think.. So you said that the 50watt woofer is ok with my amplifier, right?


Hi,

the 5OW bass/mid driver will be fine with a 40W amplifier.
If you want to design it yourself you should understand
how all the designs in the first few links are arrived at.

You will have to do the same amount of work yourself.

I you don't / cannot then your design procees will likely be wrong.
Zaphaudio has test info on your tweeter choice and the bass/mid I think.

Your driver choice of the two affects sensitivity, cabinet size and
bass extension, it has little to do with the drivers power handling.

rgds, sreten.
 
I would like to build the project by my own. Peerless are fairly easy speakers for crossovers i think.. So you said that the 50watt woofer is ok with my amplifier, right?

Hi Paco,

The power of a speaker is most mentioned and is only a figure about amount of energy it can bare.

It is more interesting if the driver you choose wil be able to reproduce low frequency in its lineair drive of the loudspeakermotor.

This figure you can find in Xmax. you can have a driver of 100W witch becomes troubles at 20W because it is at his maximum extrusion. So not the power consumption is then the problem but the mechanical limits.

When you simulate your enclosure in Winisdpro (freeware) you can see what the driver xmax does in the box at your given power.

Then again one shout not speak to much about maximum power but about maximum spl at maximum power then at means some thing and what the frequency response.
Because it is interesting how much sound you can create with the loudspeaker.

Why these older peerless drivers. I like the new peerless glasfiber cone 6,5" or aluminium types.
[IMGHTTPDEAD]http://www.europe-audio.nl/img/Data/HQ/830990.gif[/IMGHTTPDEAD]

see attachement I did simulate that driver and also at 50W you see it works fine although it can be smart to protect the driver for to much power under 40Hz by a series highpass with the woofer.
 

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Thanks guyz.

glasfiber or aluminium types are trickier to crossover i think. so i conclude on the older versions. is there any advantage of the glasfiber over the other? or only just because is a newer version you told me to go for these?

Does any of you know if the lm3886 can handle an impedance of 3.5ohm?
 
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Thanks guyz.

glasfiber or aluminium types are trickier to crossover i think. so i conclude on the older versions. is there any advantage of the glasfiber over the other? or only just because is a newer version you told me to go for these?

Does any of you know if the lm3886 can handle an impedance of 3.5ohm?
The advantage of a harder cone better detail, low distorsion. Looks good

It is trickier to cross although the 6.5" doesn't backup nasty. But I can't find a response curve for now it seems that they redraw the first published data.
 
if i use this vifa tweeter XT25TG-30/04 - Vifa 1 inch tweeter dual concentric diaphragm wave-guide center plug - Europe Audio which has impedance at 4ohms, the combined impedance of the speakers(simulated with xover pro) is 2.7 [email protected] (2order LR filter at 2khz, with zobel on woofer)

can i use a resistance of 1ohm(instead of Lpad) BEFORE the high pass filter?is this ok? this will fill the impedance at 4ohm lowest.this will do the attenuation also at 2.2db.

Hi,

Have you included BSC for the woofer ? The tweeter attenuation needs
to be more than that. You don't use 2nd order L/R values in a properly
designed crossover, see the links I posted earlier.

rgds, sreten.
 
When designing a second order Linkwitz/Reilly crossover, your target is to get the acoustic slopes to be 2nd order L/R - the electrical component values almost never correspond to the textbook values. You'll probably end up with just an inductor and the zoebel.

To really do a proper job of designing a crossover you need to measure the driver responses in your boxes and design the crossover from there. You can get close with a good ear and others' data, and at least have some fun and learn something in the process.

The energy in music at your crossover frequency is low enough that I wouldn't expect your amp to have a problem with the dip, as long as you didn't skimp on heat sinks.

Yes, you can use a series resistor ahead of your tweeter for attenuation.
 
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Hi,

Your c/o calculator is useless for real speakers, look at the links I provided,
none of them do it that way because it is not the way to do it. for a 6.5"
2 way you'd be hard pushed to better : Zaph|Audio - ZA-SR71
https://www.madisound.com/store/product_info.php?products_id=8307
https://www.madisound.com/store/product_info.php?products_id=8306

And at the rate your going with your own design and the mistakes you are
making you are highly advised for your first build to the use all the hard
work of someone who absolutely knows what they are doing, here J.K.

If you want smaller and high value look no further than :
Zaph|Audio - ZMV5 - MCM / Vifa 5" System

Also see Zaphs comphrehensive driver tests.

Your not using the information that is out there, stuff you need
to learn to design your own speakers properly, to a standard
where designing a speaker yourself makes sense.

rgds, sreten.

Paul Carmody's DIY Audio Projects - undefinition
Zaph|Audio
FRD Consortium tools guide
RJB Audio Projects
Speaker Design Works
HTGuide Forum - A Guide to HTguide.com Completed Speaker Designs.
Humble Homemade Hifi
Click below to go to
Quarter Wavelength Loudspeaker Design
The Frugal-Horns Site -- High Performance, Low Cost DIY Horn Designs
Linkwitz Lab - Loudspeaker Design
Music and Design
 
pico, some reading for you:
Passive Crossover Network Design

Also, bear in mind that some of those given to imperious statements have never
been known to build an actual set of speakers, don't let them grind you down...

Hi,

Oh I've built them, but years ago, not recently, and I did it fairly wrong.
Thats why I stopped doing it, not enough information, and the fact
that used loudspeakers offer a lot more VFM than building new ones.

If was to build some nowadays I'd use all the information I could get.
Just going through other peoples designs you could build IMO you will learn
a lot more more than simply progressing with your own ideas of the way of
doing things, I'm not trying to grind anyone down, just point to the light.

The simple fact is without measuring equipment, and a raft of modeling tools
the idea you can design something yourself on paper using a c/o calculator,
is so wrong, it needs to be expressly pointed out IMO, analysing the designs
I linked to most things should become self evident.

I've never built most of the circuits I analysed and learnt in my youth,
who has ? and what difference would it make ? Does an analysis of
a phono pre-amp depend on whether you build it or not ? The only
thing that does is what it actually sounds like, and thats got a
lot to do with issues a SPICE emulator does not reflect.

rgds, sreten.
 
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