It is currently Mon Mar 16, 2020 7:39 pm

All times are UTC - 7 hours



Post new topic Reply to topic  [ 70 posts ]  Go to page Previous  1, 2, 3, 4, 5  Next
Go to page Previous  1, 2, 3, 4, 5  Next
Author Message
Post subject: Re: While we are on the subject of speaker cabs - Wattage
Posted: Wed Sep 05, 2012 7:22 am
Offline
Professional Musician
Professional Musician
User avatar

Joined: Thu Oct 14, 2010 8:54 am
Posts: 1179
Location: Florida
bluesky636 wrote:
demaria.daniel wrote:
bluesky636 wrote:
Two 30 watt speakers will also work as amp power is divided equally between the two if they are connected in series and the impedance of each is the same. If the speakers are connected in parallel, you would probably want them both to be 60 watts as each speaker is seeing the full power output of the amp.


If I'm plugging one speaker into my 60s Bassman's main speaker out, and a second speaker is connected in to the extension speaker out, am I running them in parallel?

Concerned because I have one 50-watt speaker and one 30-watt speaker, and the amp is rated at 50-watts, so I'll need to be sure to rewire to series if this is the case.

I thought I'd done my research but it looks like I got my wires crossed somewhere!


I have no idea. Which 60's Bassman? What does the schematic show for the speaker output? What impedance is the amp designed to drive? 2, 4, 8, 16 ohms? What are the speaker impedances? Not enough information in your question to provide an answer.


Good point, I should have waited before I replied. But most were parallel.

Art


Top
Profile
Fender Play Winter Sale 2020
Post subject: Re: While we are on the subject of speaker cabs - Wattage
Posted: Wed Sep 05, 2012 8:26 am
Offline
Hobbyist
Hobbyist

Joined: Sun Nov 06, 2011 5:47 am
Posts: 78
Right!

1967 Bassman Amp
AB165 circuit, 4 ohms nominal

Schematic:
http://www.davidsonamp.com/sf/images/bassmanab165.gif
I'll need help reading that; I can clearly see where the ext. speaker out is but that's about as far as I get.

Speakers are both 8 ohms


I'd thought that when run in parallel, both speakers are handling half the power output. I'd never seen any mention on guitar amp sites that when run in parallel, both speakers are handling the total power output. Now when I search on google I find this mentioned on power amp sites, but I'd never found it on guitar amp sites before. I clearly overlooked something.


Last edited by demaria.daniel on Wed Sep 05, 2012 8:35 am, edited 1 time in total.

Top
Profile
Post subject: Re: While we are on the subject of speaker cabs - Wattage
Posted: Wed Sep 05, 2012 8:32 am
Offline
Professional Musician
Professional Musician
User avatar

Joined: Thu Oct 14, 2010 8:54 am
Posts: 1179
Location: Florida
so you can put the speakers in a single cabinet (wired in parallel) or separate cabinets, one going to the main jack and the other to the Ext.Spkr. Jack.

Art


Top
Profile
Post subject: Re: While we are on the subject of speaker cabs - Wattage
Posted: Wed Sep 05, 2012 3:18 pm
Offline
Rock Star
Rock Star

Joined: Mon Apr 05, 2010 2:37 pm
Posts: 8708
Location: Natural Bridge, Virginia
demaria.daniel wrote:
Right!

1967 Bassman Amp
AB165 circuit, 4 ohms nominal

Schematic:
http://www.davidsonamp.com/sf/images/bassmanab165.gif
I'll need help reading that; I can clearly see where the ext. speaker out is but that's about as far as I get.

Speakers are both 8 ohms


I'd thought that when run in parallel, both speakers are handling half the power output. I'd never seen any mention on guitar amp sites that when run in parallel, both speakers are handling the total power output. Now when I search on google I find this mentioned on power amp sites, but I'd never found it on guitar amp sites before. I clearly overlooked something.


Yes, all speakers are wired in parallel, even the external (Funny. Since this is a head, even the main speakers are, by definition, external. :lol: )

Two 8-ohm speakers in parallel is 4-ohms. Adding another 8-ohm cab via the external jack would bring the load down to 2-ohms which the OT may or may not be able to handle.

Assuming both speakers are the same impedance, two parallel speakers will each see 1/2 the output of the amp. Two series speakers will also see 1/2 of the total output.

_________________
Bill

Image


Last edited by bluesky636 on Wed Sep 05, 2012 8:54 pm, edited 1 time in total.

Top
Profile
Post subject: Re: While we are on the subject of speaker cabs - Wattage
Posted: Wed Sep 05, 2012 3:19 pm
Offline
Rock Star
Rock Star

Joined: Mon Apr 05, 2010 2:37 pm
Posts: 8708
Location: Natural Bridge, Virginia
Art1 wrote:
so you can put the speakers in a single cabinet (wired in parallel) or separate cabinets, one going to the main jack and the other to the Ext.Spkr. Jack.

Art


See my response to demaria.daniel.

_________________
Bill

Image


Top
Profile
Post subject: Re: While we are on the subject of speaker cabs - Wattage
Posted: Wed Sep 05, 2012 5:05 pm
Offline
Professional Musician
Professional Musician
User avatar

Joined: Thu Oct 14, 2010 8:54 am
Posts: 1179
Location: Florida
bluesky636 wrote:
Art1 wrote:
so you can put the speakers in a single cabinet (wired in parallel) or separate cabinets, one going to the main jack and the other to the Ext.Spkr. Jack.

Art


See my response to demaria.daniel.


Yeah, I wasn't asking, I was making a statement. I guess I should have made that clearer.

Art


Top
Profile
Post subject: Re: While we are on the subject of speaker cabs - Wattage
Posted: Wed Sep 05, 2012 6:07 pm
Offline
Professional Musician
Professional Musician

Joined: Sun Nov 20, 2011 3:16 am
Posts: 2337
demaria.daniel wrote:
Right!

1967 Bassman Amp
AB165 circuit, 4 ohms nominal

Schematic:
http://www.davidsonamp.com/sf/images/bassmanab165.gif
I'll need help reading that; I can clearly see where the ext. speaker out is but that's about as far as I get.

Speakers are both 8 ohms


I'd thought that when run in parallel, both speakers are handling half the power output. I'd never seen any mention on guitar amp sites that when run in parallel, both speakers are handling the total power output. Now when I search on google I find this mentioned on power amp sites, but I'd never found it on guitar amp sites before. I clearly overlooked something.



Looks good to me ~ 4 ohms into two 8-ohm speakers.
Imagine the 1950s 4x10 Bassmans with 2 ohms into four 8-ohm speakers.

_________________
Image


Top
Profile
Post subject: Re: While we are on the subject of speaker cabs - Wattage
Posted: Wed Sep 05, 2012 6:39 pm
Offline
Rock Star
Rock Star

Joined: Mon Apr 05, 2010 2:37 pm
Posts: 8708
Location: Natural Bridge, Virginia
Art1 wrote:
bluesky636 wrote:
Art1 wrote:
so you can put the speakers in a single cabinet (wired in parallel) or separate cabinets, one going to the main jack and the other to the Ext.Spkr. Jack.

Art


See my response to demaria.daniel.


Yeah, I wasn't asking, I was making a statement. I guess I should have made that clearer.

Art


Oh. Sorry.

I hope I have answered all of your questions. Anything else just post it or send me a PM and I will be happy to help. :D

_________________
Bill

Image


Top
Profile
Post subject: Re: While we are on the subject of speaker cabs - Wattage
Posted: Wed Sep 05, 2012 7:04 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Tue Jun 29, 2010 1:20 pm
Posts: 9640
Location: Indiana
demaria.daniel wrote:
...I'd thought that when run in parallel, both speakers are handling half the power output...


Yes, whether they are series or parallel, the total power output from the amp will divide roughly evenly between the two speakers if each speaker is the same impedance. The speakers work just like any impedance in a circuit.

Both speakers in parallel see the same voltage from the amp, but the current divides into two, half of the current from the amp going to each speaker.

Both speakers in series see the same current from the amp, but the voltage divides into two, half of the voltage from the amp going to each speaker.

So, whether speakers are wired in either series or parallel, the amp's output power must follow Ohm's law and divide according to the impedance in the circuit. Or, use Kirchoff's law, whichever you prefer. :lol:

If you blow one of two speakers in parallel, then the remaining speaker will get the entire amp output power. If you blow either of two speakers in series, the amp will then self-destruct as there is no load at all on the output, open circuit.

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.


Top
Profile
Post subject: Re: While we are on the subject of speaker cabs - Wattage
Posted: Wed Sep 05, 2012 7:42 pm
Offline
Hobbyist
Hobbyist

Joined: Sun Nov 06, 2011 5:47 am
Posts: 78
shimmilou wrote:
Yes, whether they are series or parallel, the total power output from the amp will divide roughly evenly between the two speakers if each speaker is the same impedance. The speakers work just like any impedance in a circuit.


Dude, thank you. :lol:

I can't tell you how stressed I was for the past hour thinking I was going to blow a brand new speaker because of some mix up. So relieved!


Top
Profile
Post subject: Re: While we are on the subject of speaker cabs - Wattage
Posted: Wed Sep 05, 2012 7:43 pm
Offline
Professional Musician
Professional Musician

Joined: Fri Jun 26, 2009 6:53 pm
Posts: 2252
Location: Harvard IL
Yep, concurr with Shimmy. Two 8ohm speakers in parallel with that amp is the deal. A 50 and 30 watt are fine, unless you operate the amp at a very high volume most of the time. Yeah, I consider a parallel set-up safer for the amp. Some folks prefer a series set-up, for the sake of tone, and that's OK!!! Art

_________________
None of Us are free, if One of Us is chained !


Top
Profile
Post subject: Re: While we are on the subject of speaker cabs - Wattage
Posted: Wed Sep 05, 2012 8:50 pm
Offline
Rock Star
Rock Star

Joined: Mon Apr 05, 2010 2:37 pm
Posts: 8708
Location: Natural Bridge, Virginia
shimmilou wrote:
demaria.daniel wrote:
...I'd thought that when run in parallel, both speakers are handling half the power output...


Yes, whether they are series or parallel, the total power output from the amp will divide roughly evenly between the two speakers if each speaker is the same impedance. The speakers work just like any impedance in a circuit.

Both speakers in parallel see the same voltage from the amp, but the current divides into two, half of the current from the amp going to each speaker.

Both speakers in series see the same current from the amp, but the voltage divides into two, half of the voltage from the amp going to each speaker.

So, whether speakers are wired in either series or parallel, the amp's output power must follow Ohm's law and divide according to the impedance in the circuit. Or, use Kirchoff's law, whichever you prefer. :lol:

If you blow one of two speakers in parallel, then the remaining speaker will get the entire amp output power. If you blow either of two speakers in series, the amp will then self-destruct as there is no load at all on the output, open circuit.


My apologies to all concerned. I totally ignored the fact in a parallel connection, each speaker sees the same voltage but half the current. In a series connection, each speaker sees the same current but half the voltage (assuming all are the same impedance). Chalk it up to old age/brain fart/what have you. I have corrected my earlier posts. :oops:

_________________
Bill

Image


Top
Profile
Post subject: Re: While we are on the subject of speaker cabs - Wattage
Posted: Thu Sep 06, 2012 1:45 am
Offline
Professional Musician
Professional Musician

Joined: Sun Nov 20, 2011 3:16 am
Posts: 2337
aclempoppi wrote:
Yep, concurr with Shimmy. Two 8ohm speakers in parallel with that amp is the deal. A 50 and 30 watt are fine, unless you operate the amp at a very high volume most of the time. Yeah, I consider a parallel set-up safer for the amp. Some folks prefer a series set-up, for the sake of tone, and that's OK!!! Art


Art. Interested towards your statement:

Advantages/Disadvantages of Parallel vs Serial?
Safer for the amp? Why?
Tone? Why?
Other advantages or disadvantages?

Just interested. Thank you. Toppscore :)

_________________
Image


Last edited by Toppscore on Thu Sep 06, 2012 1:50 am, edited 1 time in total.

Top
Profile
Post subject: Re: While we are on the subject of speaker cabs - Wattage
Posted: Thu Sep 06, 2012 1:48 am
Offline
Professional Musician
Professional Musician

Joined: Sun Nov 20, 2011 3:16 am
Posts: 2337
bluesky636 wrote:
shimmilou wrote:
demaria.daniel wrote:
...I'd thought that when run in parallel, both speakers are handling half the power output...
Yes, whether they are series or parallel, the total power output from the amp will divide roughly evenly between the two speakers if each speaker is the same impedance. The speakers work just like any impedance in a circuit. Both speakers in parallel see the same voltage from the amp, but the current divides into two, half of the current from the amp going to each speaker. Both speakers in series see the same current from the amp, but the voltage divides into two, half of the voltage from the amp going to each speaker. So, whether speakers are wired in either series or parallel, the amp's output power must follow Ohm's law and divide according to the impedance in the circuit. Or, use Kirchoff's law, whichever you prefer. :lol: If you blow one of two speakers in parallel, then the remaining speaker will get the entire amp output power. If you blow either of two speakers in series, the amp will then self-destruct as there is no load at all on the output, open circuit.
My apologies to all concerned. I totally ignored the fact in a parallel connection, each speaker sees the same voltage but half the current. In a series connection, each speaker sees the same current but half the voltage (assuming all are the same impedance). Chalk it up to old age/brain fart/what have you. I have corrected my earlier posts. :oops:





Brain Farts are good. Means you're alive & clickin' :shock:
Chicks DIG Brain Farts :lol:

_________________
Image


Top
Profile
Post subject: Re: While we are on the subject of speaker cabs - Wattage
Posted: Thu Sep 06, 2012 4:23 am
Offline
Aspiring Musician
Aspiring Musician
User avatar

Joined: Sat Mar 31, 2012 6:38 am
Posts: 593
Toppscore wrote:
aclempoppi wrote:
Yep, concurr with Shimmy. Two 8ohm speakers in parallel with that amp is the deal. A 50 and 30 watt are fine, unless you operate the amp at a very high volume most of the time. Yeah, I consider a parallel set-up safer for the amp. Some folks prefer a series set-up, for the sake of tone, and that's OK!!! Art


Art. Interested towards your statement:

Advantages/Disadvantages of Parallel vs Serial?
Safer for the amp? Why?
Tone? Why?
Other advantages or disadvantages?

Just interested. Thank you. Toppscore :)


Reread the posts in this thread to get most of your answers.

_________________
...I for one, sure would appreciate the return of intelligent conversation, spirit of assistance and the simple yet effective ignoring of those who can't seem to hang with that...
Best regards,
rob


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 70 posts ]  Go to page Previous  1, 2, 3, 4, 5  Next
Go to page Previous  1, 2, 3, 4, 5  Next

All times are UTC - 7 hours

Fender Play Winter Sale 2020

Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to: