Replace speaker to hit overdrive sooner?

vipergts2207

Junior Member
Joined
Jan 26, 2021
Messages
20
Reaction score
18
I’ve got a Marshall DSL20CR and I’m planning on replacing the speaker with either a greenback or creamback. While I’m at it, I’m curious if I can get the amp to overdrive at lower volumes by replacing the speaker with one of a different impedance than the 16 ohm one that’s in there now.
 

cybermgk

“Happiness is the most insidious prison of all"
Gold Supporting Member
V.I.P. Member
Joined
Jul 7, 2011
Messages
15,212
Reaction score
21,746
Unless the Output Transformer has additional taps for other impedences, all you will do is damage the amp. Being a combo, that would mean a external speaker jack listed with another impedance, , an impedence switch, or additional wires from the OT.
 

vipergts2207

Junior Member
Joined
Jan 26, 2021
Messages
20
Reaction score
18
It’s got a three outputs, one 16 ohm output and two others for either one 8 ohm speaker or two 16 ohm speakers.
 

Zacknorton

Banned
Joined
Nov 21, 2014
Messages
154
Reaction score
164
Impedance isn’t the key. Speaker Efficiency and breakup characteristics are way more useful to hitting your goals.

you could go for a speaker that’s really inefficient and prone to early breakup and you could shave off 6db or so in volume. That’s a pretty big shift.

Or you could look into the speakers that offer some sort of efficiency based atrnuation. Eminence has a couple models FDM, I think they call it.
There are other speakers that do the same kind of thing but are $$$$$$$$$money.
 

vipergts2207

Junior Member
Joined
Jan 26, 2021
Messages
20
Reaction score
18
I found a link that would seem to indicate that I could connect an 8 ohm speaker to the 16 ohm output and no harm would be done.


  • If speaker impedance is lower than amp impedance, the amp needs to work harder to get the same output level as with an impedance match. Since a tube-amp is limited to how much power it can give, it can never damage itself. The tubes get worn out faster (since they have to work harder) and the amp won’t seem to be as loud as with an impedance match.


Is this correct?

The Creambacks are slightly less efficient than the Seventy/80 that’s in there now, not by much though.
 

el84ster

Senior Member
Joined
Jan 25, 2014
Messages
381
Reaction score
423
Inefficient speakers are the best sounding way to make an amp more usable, IMO.
The difference between a 100db speaker and 94db is huge. It’ll let you turn your volume up about two numbers for the same volume level out front.

that’s often enough to get some hair on the amp and have it sound great when hit with a drive pedal all at very sane volumes.
 

Zacknorton

Banned
Joined
Nov 21, 2014
Messages
154
Reaction score
164
You can mismatch the impedance to a degree. But it’s not going to give you anything near what going with a much less efficient speaker will give you.

seriously. FDM speakers from eminence.
 

dspelman

Senior Member
Joined
Apr 30, 2009
Messages
11,309
Reaction score
7,827
You should probably google Fluxtone speakers.
Because Fluxtone replaces the original magnet with what amounts to a variable electromagnet, it's possible to get the same sound quality at up to 25 dB lower than the full-efficiency speaker. That's the volume equivalent of running your 30W amp at 1/8th watt.
 

Lester

Senior Member
Joined
Mar 18, 2007
Messages
917
Reaction score
420
You should probably google Fluxtone speakers.
Because Fluxtone replaces the original magnet with what amounts to a variable electromagnet, it's possible to get the same sound quality at up to 25 dB lower than the full-efficiency speaker. That's the volume equivalent of running your 30W amp at 1/8th watt.
Those are cool... but they hit the budget a wee bit hard.

Do you know anyone who has tried them?
 

dspelman

Senior Member
Joined
Apr 30, 2009
Messages
11,309
Reaction score
7,827
Those are cool... but they hit the budget a wee bit hard.

Do you know anyone who has tried them?
I have, actually. I first found them at the LA Amp Show several years ago. In case you've never been, it's held in an airport hotel next to the Van Nuys airport, which has every kind of personal, commercial and military aircraft blasting off around the clock. So the rooms at the hotel are soundproofed beyond the ordinary, and they put the show in a single wing. Each vendor has his own room (no beds, of course) and you can close the door and crank the hell out of whatever you have. I walked into one room with a bunch of other people, and they closed the door. There was a guy there with a cranked amp, whanging away. Another guy walked up next to it and started turning a knob. The sound quality didn't change, but the volume dropped to the point where all you could hear were the jaws dropping on the floor.

Later I ran into one of them at a recording studio and spent a couple of days with it. They use the moving parts (and basket, of course) from speakers you know and love; this is where the distinctive sound comes from. And then they sub in their magnet setup. Unlike an attenuator, which inserts itself into the output transformer/voice coil circuit, the Fluxtone doesn't change the things that make the sound. They just reduce the efficiency of the speaker. A lot.

These are useful, really, only for tube amps. And they *are* pricey. But if that overdriven tube sound is what you want, and the volume is not, this is the way to go.
 

Lester

Senior Member
Joined
Mar 18, 2007
Messages
917
Reaction score
420
I have, actually. I first found them at the LA Amp Show several years ago. In case you've never been, it's held in an airport hotel next to the Van Nuys airport, which has every kind of personal, commercial and military aircraft blasting off around the clock. So the rooms at the hotel are soundproofed beyond the ordinary, and they put the show in a single wing. Each vendor has his own room (no beds, of course) and you can close the door and crank the hell out of whatever you have. I walked into one room with a bunch of other people, and they closed the door. There was a guy there with a cranked amp, whanging away. Another guy walked up next to it and started turning a knob. The sound quality didn't change, but the volume dropped to the point where all you could hear were the jaws dropping on the floor.

Later I ran into one of them at a recording studio and spent a couple of days with it. They use the moving parts (and basket, of course) from speakers you know and love; this is where the distinctive sound comes from. And then they sub in their magnet setup. Unlike an attenuator, which inserts itself into the output transformer/voice coil circuit, the Fluxtone doesn't change the things that make the sound. They just reduce the efficiency of the speaker. A lot.

These are useful, really, only for tube amps. And they *are* pricey. But if that overdriven tube sound is what you want, and the volume is not, this is the way to go.
Sounds great... but I think I'll have to wait for the Chinese models to come out.
 

Brek

Gold Supporting Member
Joined
May 15, 2020
Messages
1,569
Reaction score
1,398
I tried a lower db rated speaker on my 1 watter, it did make a difference, but not as much as I’d expected, 95db down from a 98db was not massive. But did allow me to drive the amp up full without ears ringing.
 

stp

Senior Member
Joined
Jun 3, 2015
Messages
179
Reaction score
95
put a 15 watt speaker that mite do it
 

CB91710

Double Platinum Supporting Member
Silver Supporting Member
Joined
Jul 19, 2019
Messages
7,842
Reaction score
16,090
On paper, running a 16 ohm speaker on the 8 ohm output will result in half the wattage.
In your ears, you are not going to hear a difference in volume. Maybe some loss of high frequencies due to the impedance mismatch.

ANY amp over 5 watts is going to be "too loud" by the time you drive the output into breakup.

Spend the money on a good attenuator... at least on the level of a Weber Mass... and keep your impedances matched.
 

vipergts2207

Junior Member
Joined
Jan 26, 2021
Messages
20
Reaction score
18
Thanks for the input everyone. I opted to go for a Neo Creamback which is only down 1 dB from the existing 70/80. I’ll look into getting an attenuator at some point.
 

CB91710

Double Platinum Supporting Member
Silver Supporting Member
Joined
Jul 19, 2019
Messages
7,842
Reaction score
16,090
Thanks for the input everyone. I opted to go for a Neo Creamback which is only down 1 dB from the existing 70/80. I’ll look into getting an attenuator at some point.
You won't hear 1db.
3db is the minimum detectable change, and takes a doubling or halving of power.
10db is perceived as being half/twice as loud.
 


Latest Threads



Top