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Can anyone help me with this new speaker project I have ?
I want to build some new tower speakers using 2 HiVi B4N 4"copper color cone full ranges the max wattage on each is 30w max an one bullet tweeter about 40w max. My question is what would be the safest crossover wattage to pair with this configuration? i have looked at some 2 ways - mostly 100w. I will be using these as midranges but i would still like to hear some decent bass. I have a sub as well so my deep bass will be present. My receiver Yamaha HTR 5830 100w per channel 5.1 system I don't want to blow out my project any suggestions?
 
100 watt one will surely not fry.
hooking it up to an off the shlef xover NOT made for Your drivers will have its own effects.

My suggestion would be to post as many specs You can on Your choosen drivers,
and maybe the community can help You to design an xover that will at least work close enough as intended. BTW, probably its cheaper to make Your own xover anyways.
Purchase an "good for any driver" xover usualy ends up in puting that to the waste bin, and building Your own. So You can save time and money, and efforth if You just do not purchase any pre-built thingy.
 
question, does it absolute needs to be MTM ?
reason for this question is simple, usualy one of the less involving solutions to get a decent pair of speakers is the tipical 6.5" midbass and a proper tweeter combo.
Surely a 1-way fullrange is even less of a pain, but that might just cost a bit too mutch.

If You allready got them drivers, and building he linked project, just as it has been pointed out You may run into problems with impedance. On the other hand, i would not worry about that.
More than probably Your reciver has overload protection.
Other than that, the hivi drivers will probably not handle a high input anyways.
So it just means that You will not -probably- turn the volume up to the lvl where You could damage Your equipment.
If You want to be extra safe, You can simply add a regular FUSE , that should protect the amplifier from supplying too high currents.
OR, clumsy, but still a solution is to grab 10 pieces of 10 watt, 40 ohm resistors and wire them in paralell, and wireing this in series to the speakers. Notice, You will be heating away approx. half of the amplifier power in this case, on the resistors. This is a verry last resort option, not an advice to follow.

If You plan on MTM, You need 16 ohm midbass drivers. 4 Ohm can be used too, but it has its own set of problems, paralell connecting 16 ohm rated ones is the preferd solution.
 
your Yamaha receiver is not rated to drive 4 ohm speakers, so using the MTM's would lead to
issues, more distortion and possibly even taking out the power amp and speaker along with it.

Hi,

Whilst you are correct, on the 6 ohm setting it will work, but there will
be a possibility the receiver goes into shut down mode at high volumes.

IMO unless your really into cranking it, the arrangement will be fine.

But of course Overnight Sensations - undefinition would be
certainly a higher cost vs performance option, better suited.

rgds, sreten.
 
6 ohm setting? Most 8 ohm speakers are really ~6 ohms. and paralleled is approaching 3 ohms in the mid bass frequencies.
Even if you say I'll never crank it, there are times depending on source music, mistakes on selecting inputs with different levels, etc. It's just plain 'bad advice' to recommend a system that uses 3 ohm-ish speakers on under designed ie low current power amps.
It's also very bad practice to depend on "protection modes" on consumer gear to save amps and speakers, the situation is worse on some so called "Hi End" gear.
 
6 ohm setting? Most 8 ohm speakers are really ~6 ohms. and paralleled is approaching 3 ohms in the mid bass frequencies.
Even if you say I'll never crank it, there are times depending on source music, mistakes on selecting inputs with different levels, etc. It's just plain 'bad advice' to recommend a system that uses 3 ohm-ish speakers on under designed ie low current power amps.
It's also very bad practice to depend on "protection modes" on consumer gear to save amps and speakers, the situation is worse on some so called "Hi End" gear.

Hi,

Whilst your opinion may be as valid as mine, please don't present it as fact.

The receiver in question has a 6/8 ohm setting, and the OS MTM is 4 ohms
minimum, looking at the impedance curve a 6 ohm rating is quite plausible,
it will work quite well. It will not blow up or go into premature protection.
Protection is needed for all speakers regardless of impedance in AV gear.

rgds, sreten.
 
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Bad advice is bad advice,
The MTM graph can't be read with any resolution with the vertical scale as presented. The MTM minimum impedance at a couple of hundred Hz can be calculated quite accurately. Rmin = 3.71 ohms. this is very low and needs a high current amplifier, sorry this Yamaha ain't cutting the mustard, it's not an opinion.

On the Yamaha HT there is no 6 ohm setting! It's called specmanship. calling out as 6/8 ohm in the spec only, at the same power rating none the less. Most SS high current amps will actually have more power available at lower impedances, and this one doesn't. I'm sure they added the 6 ohm rating knowing most 8 ohm speakers are closer to 6 ohm.
Another good clue about this Yamaha is the speaker selector is A or B ONLY, again most high current designs supporting 4 ohm, will have the ability to do A plus B, a feature that is desirable, but only available on higher end models.
Inexpensive HT receivers like this are notoriously stingy with expensive output transistors and heat sinks,. They do this to meet a price point. If you know about amplifier design you would agree that asking an amp rated at 100W at 6/8 ohm with a single pair of power devices will have a SOA problem at 4 ohm, and likely to burn stuff trying to deliver twice the wattage at 4 ohm. Voltage amps don't know any better, they will try to deliver the same output voltage no matter what the load. probably the only thing helping here is the stingy PS ratings.
Amplifier protection circuits don't always work very fast or reliably when they are needed most ie being abused with low ohm load.
 
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