Speaker Cabinet - diyAudio
Go Back   Home > Forums > Live Sound > Instruments and Amps

Instruments and Amps Everything that makes music, Especially including instrument amps.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 8th March 2011, 02:32 AM   #1
diyAudio Member
 
Join Date: Nov 2010
Question Speaker Cabinet

Hello to all.

I am getting a Line 6 Spider IV HD150 150W Guitar Amp Head, which i heat is a great modeling amp. And i want to build the cabinet for this amp to save money.

First question. How many speakers can it take, half stack, or full.

second, For what i am doing, what speakers should i use.
recomandations please. Details:
i am doing light gigging, using for recording and use in the home.
using drop tunings as low as drop C
want a darker kind of sound, like low ends.

Third, open back or closed, or even vented? For what i am doing, what is best??

Fourth, how should the speakers be wired. I dont have a firm understanding in the impendance of speakers. so help me please.

Thanks
  Reply With Quote
Old 8th March 2011, 03:08 AM   #2
diyAudio Member
 
picowallspeaker's Avatar
 
Join Date: Apr 2007
Great questions !
The speakers are produced in 4 ,8 or 16 Ohm impedance ,so-called nominal because it changes when a musical signal is applied to speaker's terminals .
Amplifiers are targeted to reach a certain power under a certain load . And they like to distort on lower impedance loads ,which is no good -it's not the same 'overload distortion' made by saturating the inputs ,it just cooks the power devices . So to mantain a certain load seen by the amplifier , speakers can be series or parallel connected ,if four ,they can be paralleled in pairs then series to another paralleled pair . Note that we're using the same speaker .
So the equation of paralleled resistances (which speakers are not ,but impedance sum and divide as resistance ) is simplified : when two 8 Ohm speakers are paralleled ,total impedance would be 4 Ohm . In series = 16 Ohm
Series-parallel ( 4 drivers)= 8 Ohm
The choice of type of cabinet ,open ,vented or closed depends from speaker's characteristcs (parameters ) and from what you prefer most .
  Reply With Quote
Old 8th March 2011, 03:14 AM   #3
diyAudio Member
 
Join Date: Nov 2010
Thanks for the quick reply. So, if an amp, say, had a speaker cap of two 8 Ohm speakers in series, it could handle eight speakers in the series-parallel? Is the bigger the speaker best for the low range sound reproduction of a guitar??
  Reply With Quote
Old 8th March 2011, 03:25 AM   #4
diyAudio Member
 
picowallspeaker's Avatar
 
Join Date: Apr 2007
When talking about speakers and sound ,we talk about compromises . And good sense.
An amplifier is able to control a single thin wire immersed in a magnetic flux ,which may seem strange, but it isn't ,since loudspeakers are very inefficient devices . that because they have a certain mass attached to the voice coil former ,and an inner and a surround retention spring to keep it operating . they are called mechanical and electrical 'friction' .
.....More to come

  Reply With Quote
Old 8th March 2011, 03:38 AM   #5
diyAudio Member
 
Join Date: Nov 2010
So would i be able to use a full stack? It is stereo, does that mean that i could put cabs on either side of the stage??
  Reply With Quote
Old 8th March 2011, 04:02 AM   #6
diyAudio Member
 
picowallspeaker's Avatar
 
Join Date: Apr 2007
Well- good news !!!
When putting two drivers aside ,output increases by +3 dB(doubles).
If they are parallel connected ,current flows 1/2 in each ,so you'll have to turn the knob to have more volume . no energy is lost ,no energy is created .
Amplifier power in Watts is dictated by its transformer size , efficiency being arguable in the 70 % range if it operates in class AB .
Sorry but I suffer from hi-fi addiction ,where driver sensibility is in the 85-95 dB/W/m range . 95 dB for me is very high (relatively) sensibility ; it means that when delivered 1 Watt ,it produces a sound 95 db loud ,measured at 1 m.
So if you take a look at the listings of various manufactures , you'll be likely to choose from the 'Pro' audio stuff ,which are almost all high sensibility speakers.
  Reply With Quote
Old 8th March 2011, 04:49 AM   #7
diyAudio Member
 
Join Date: Nov 2010
It is a 150 watt amp with stereo channel output. I just have trouble finding the impendance output. I hear it works with a halfstack, but i dont know how it is wired, so i have no idea on impendance
  Reply With Quote
Old 8th March 2011, 06:28 AM   #8
diyAudio Member
 
chris661's Avatar
 
Join Date: Feb 2008
Location: Sheffield
Blog Entries: 8
Almost everything with a solid state amplifier will drive 8ohms comfortably. Most will drive 4ohms, but a lower impedance increases the current draw from the amplifier, putting everything under more stress.

I would say 8ohms per channel would be okay, unless someone finds a spec sheet.
Yes, you can operate a full stack. For each cabinet, buy 4 drivers, 8ohms each. When you wire two of these in series, the impedance goes to 16ohm. When you put two of these groups in parallel, it's back to 8ohm (per cabinet), which your amplifier should be happy with.

Chris
__________________
"Throwing parts at a failure is like throwing sponges at a rainstorm." - Enzo
My setup: http://www.diyaudio.com/forums/multi...tang-band.html
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Sonotube as a speaker cabinet? MPM Multi-Way 1 21st October 2006 11:53 PM
Speaker cabinet design eitanwaks Multi-Way 47 19th September 2006 07:58 PM
Speaker Cabinet InfinityPWS Multi-Way 2 13th January 2006 02:11 PM
Rebuilding Speaker Cabinet Oddity Multi-Way 0 11th February 2005 03:19 AM
speaker cabinet material dsrviola Multi-Way 4 1st January 2003 06:28 PM


New To Site? Need Help?

All times are GMT. The time now is 08:49 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2