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What size Amp?

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SnailSpace View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SnailSpace Quote  Post ReplyReply Direct Link To This Post Posted: 12 December 2022 at 9:16pm
Originally posted by Earplug Earplug wrote:

You have missed/misunderstood the most important bit:-

"I'd also suggest avoiding any series connections UNLESS THEY ARE INSIDE A CAB, "

So I'd suggest 2 x 2x15" cabinets, with the speakers wired in series inside.

Then 2 cables going back to the amp. One per channel, normal stereo mode. Look at the diagram in the calculator link you posted earlier. It's all there.   Confused

And I don't think that Mr. Conanski will disagree there. We are both saying the same thing, albeit in a slightly different way. Canadian English v. The Queen's (King's?) Thingie!  LOL

Yeah apologies totally missed the wording 'inside'! Embarrassed Probably dismissed it as you where saying about putting 2 in one box.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 4D Quote  Post ReplyReply Direct Link To This Post Posted: 12 December 2022 at 4:49pm


And.. Once you have decided on how to wire it up .... Best practice for the low frequency feed to your bass speakers is use the crossover to set slope to LR24 & the hi pass filter at 45hz/50Hz or higher to minimise mechanical damage through over excursion.. 
DMZ. "The bass was intense. Girls were literally running up to stand next to the subs"
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Post Options Post Options   Thanks (0) Thanks(0)   Quote dj jammin Quote  Post ReplyReply Direct Link To This Post Posted: 12 December 2022 at 4:01pm
Sorry to say this but you do need to do a bit of reading up on the basics.. 
As I understand it, you want to make a 3 way stack, bass, mid, top
You are gonna need a way to split the frequencies (an active crossover ie dcx 2496)
The crossover will split your signal into bass, mid, tops at the frequencies you choose.. you will then need 3 amps/amp channels.. to power each section.

You can still wire up the BW PVs in series (two pairs each wired in series) but you will need to make a special cable or junction box to do this..

The basics you need to read up on are: ohms law and also learn how to make your own speaker cables. The widely used connector being neutrik speakon.
Reverence Sound system


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Post Options Post Options   Thanks (0) Thanks(0)   Quote KDW32 Quote  Post ReplyReply Direct Link To This Post Posted: 12 December 2022 at 3:58pm
SnailSpace what connectors do you have on the back of your speaker cabinets? Do you have a output/link socket on them as well as the input from the amp? Are the sockets/connectors the same on the back of your cabinetsb or are they random binding posts, speakons, jack's or xlrs? 

Edited by KDW32 - 12 December 2022 at 3:59pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Conanski Quote  Post ReplyReply Direct Link To This Post Posted: 12 December 2022 at 3:39pm
Originally posted by SnailSpace SnailSpace wrote:


you said don’t link in parallel as the amp would immediately shut down?
 
I said you can't connect 4 speakers together in parallel. You need to slow down and read more carefully because the small details matter. 

Originally posted by SnailSpace SnailSpace wrote:

So I presume you’re saying only option left is Stereo and surely that means I have a lot of wires feeding back to amps?
No just 1 +/- pair per channel.

Originally posted by SnailSpace SnailSpace wrote:

When ever I’ve looked at the back of stacks at sessions I’m sure they are linked in parallel or series?
They are almost certainly linked in parallel. 

Originally posted by SnailSpace SnailSpace wrote:

(I understand what I will be using as mids x4 Jamos are passive speakers and I’m currently reading up on mixing Passive & Active speakers and seems to be ok, not ideal but as I say this is the first steps.
Active speakers have an amplifier built in and as far as I know you don't have any of those. Those Jamos are 3-way fullrange passive speakers correct? Do the mid and high drivers still work?

Originally posted by SnailSpace SnailSpace wrote:

I want a one stack approach linked by short cable runs with limited longer runs going back to the amp if possible.
Should be possible. The easiest way to do this is to put all the amps in 1 rack with the crossover/DSP and place it behind the stack, then connect 1 speaker cable from each amp channel to a box and put a short jumper between it and a second box of the same type. 


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Post Options Post Options   Thanks (0) Thanks(0)   Quote SnailSpace Quote  Post ReplyReply Direct Link To This Post Posted: 12 December 2022 at 1:54pm
Yeah missed that bit where you also suggested avoiding series too.

I don’t have option of putting x2 15” in one cab for now. 

So does this mean I’m stuck with connecting in stereo as my only option and multiple wires heading to the amp ie a +- from every speaker? So x8 wires from x4 PV’s to one amp, X8 from x4 Jamo to their amp? 

I’m still confused to why Series/Parallel/Bridged aren’t an option if I have correct Amps?

I thought you could wire speakers in series/parallel outside the box? Is this where I’m confused, do most sound systems link within the boxes? So what are the linking cables I’m seeing on the outside? For me I’m trying to limit the amount and long runs of cables on the outside back to the amp or does what I have not allow for that?




Edited by SnailSpace - 12 December 2022 at 2:03pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Earplug Quote  Post ReplyReply Direct Link To This Post Posted: 12 December 2022 at 1:43pm
You have missed/misunderstood the most important bit:-

"I'd also suggest avoiding any series connections UNLESS THEY ARE INSIDE A CAB, "

So I'd suggest 2 x 2x15" cabinets, with the speakers wired in series inside.

Then 2 cables going back to the amp. One per channel, normal stereo mode. Look at the diagram in the calculator link you posted earlier. It's all there.   Confused


And I don't think that Mr. Conanski will disagree there. We are both saying the same thing, albeit in a slightly different way. Canadian English v. The Queen's (King's?) Thingie!  LOL



Earplugs Are For Wimps!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SnailSpace Quote  Post ReplyReply Direct Link To This Post Posted: 12 December 2022 at 10:09am

Originally posted by SnailSpace SnailSpace wrote:

So what type of Series configuration would I be looking at setting up?

Originally posted by Conanski Conanski wrote:

I'd also suggest avoiding any series connections unless they are inside a cab, externally wiring drivers in series requires specially wired speaker cables which are way to easy to mistake for parallel wired cables. But that bring up an interesting option, can you put 2 15's in a single cab or is everything built already?

Already have boxes I have x4 15” 150w as well as the PV’s as I say I may at later date make boxes but one step at a time. 

Interested to find why you say don’t use series when earplug reccomended series and you said don’t link in parallel as the amp would immediately shut down?

So I presume you’re saying only option left is Stereo and surely that means I have a lot of wires feeding back to amps?

When ever I’ve looked at the back of stacks at sessions I’m sure they are linked in parallel or series? Ie linked by one short external cable to each speaker from the other on each section then one cable heading back to amp? Or are they as you say wired different inside rather than just + & - terminals.

Are you and Earplug coming from different disciplines meaning different preferences or are you basing your advice on what I have and its capabilities? (I understand what I will be using as mids x4 Jamos are passive speakers and I’m currently reading up on mixing Passive & Active speakers and seems to be ok, not ideal but as I say this is the first steps. Custom boxes/additional speakers/moving around will be another step)

I want a one stack approach linked by short cable runs with limited longer runs going back to the amp if possible.

Tweeter box - ART Amp or similar (split off & boxed as - active) 
Mid - Jamos x 4 (ok not ideal as they are - passive) QSC GX3 Amp
Bass - BW PV’s x 4 (again not really bass but again boxed as - active) Amp QSC 3602 PLX or similar

Crossover


Edited by SnailSpace - 12 December 2022 at 10:52am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Conanski Quote  Post ReplyReply Direct Link To This Post Posted: 11 December 2022 at 9:08pm
Originally posted by Daniel S Daniel S wrote:

You can get an 8 Ohm load with 4*4 Ohm speakers by wiring two and two in series and then wire those in parallel to get ((4+4)+(4+4))÷2=8. 

You messed up something there because two 8ohm loads in parallel = 4ohms. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Daniel S Quote  Post ReplyReply Direct Link To This Post Posted: 11 December 2022 at 8:42pm
Originally posted by SnailSpace SnailSpace wrote:

Don’t get me wrong even using that calculator I’d be lying if I said I understand why 4x 4 ohms speakers in parallel give you an impedence of 1ohm and not four?  

Unfortunately for you I’m that student that takes x29 explanations or an epiphany for something to make sense!

I find Audio University are good videos, but this forum and yours ended have been great for giving me the time for the Penny to drop!

What type of Sound do you have yourself and what do you use it for?

When calculating total impedance for a number of speakers of the same impedance wired in parallel, you take the impedance and divide it by the number of speakers. In this example 4÷4=1. Four 8 Ohm drivers would be 8÷4=2.
When wired in series you add the numbers, ie 4+4+4+4=16
You can get an 8 Ohm load with 4*4 Ohm speakers by wiring two and two in series and then wire those in parallel to get ((4+4)+(4+4))÷2=8.



Edited by Daniel S - 11 December 2022 at 8:44pm
Distortion is evil
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Conanski Quote  Post ReplyReply Direct Link To This Post Posted: 11 December 2022 at 6:18pm
Originally posted by SnailSpace SnailSpace wrote:

What speakers would you use in bridge mode?
Forget Bridge mode... it's usually the least desirable amp config to use.

Originally posted by SnailSpace SnailSpace wrote:

So what type of Series configuration would I be looking at setting up?
I'd also suggest avoiding any series connections unless they are inside a cab, externally wiring drivers in series requires specially wired speaker cables which are way to easy to mistake for parallel wired cables. But that bring up an interesting option, can you put 2 15's in a single cab or is everything built already?

Originally posted by SnailSpace SnailSpace wrote:

Had a look at ART SLA1 & SLA2 thanks - why would I choose this type of amp over something a touch bigger but cheaper
Well you don't need something larger for tweeters and it's about sound quality. Class D amps can certainly get the job done but for a little more $$ you get less noise and smoother sound. 

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Post Options Post Options   Thanks (0) Thanks(0)   Quote SnailSpace Quote  Post ReplyReply Direct Link To This Post Posted: 11 December 2022 at 2:51pm
Don’t get me wrong even using that calculator I’d be lying if I said I understand why 4x 4 ohms speakers in parallel give you an impedence of 1ohm and not four?  

Unfortunately for you I’m that student that takes x29 explanations or an epiphany for something to make sense!

I find Audio University are good videos, but this forum and yours ended have been great for giving me the time for the Penny to drop!

What type of Sound do you have yourself and what do you use it for?
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