Slew Godzilla OPS

[rhythmsandy]

Seen the slew monsters output stage with 5 pairs of output stage so how about using 10 or 15 pairs of output pairs? call it Slew Godzilla?
what are the pros and cons of using 10 or 15 pairs of output transistors/mosfets in the output stage.

 

[Enzo]

The cons are you'd be using a lot more expensive parts, and the heat sinks would have to be two or three times the size just to fit them.

Pros? I don't know, what do you plan for this to accomplish? Unless you change the power supply, it won't increase power output. I don't know the original amp, but unless it was woefully underdesigned in the outputs, it probably had enough of them already.

 

[jkuetemann]

SlewZilla OPS, possible but would it be practical? Doubt it...

Pros might include:

The ability to use higher voltage rails for increased power output into typical impedances.
The ability to use lower than typical impedances with 'normal' power supply voltages.
The ability to use devices with poor SOA or current rating under typical conditions.



Cons will likely include:

Greatly increased construction cost due to several factors like:
More devices and supporting components to purchase
Larger chassis and heat sinks will be required
Larger PCBs will cost more, beyond certain modest dimensions this goes up exponentially
More capable PSU needed, which does not come fo free

Greater chance of error during construction, increased risk of failure couples again to cost
Increased risk to amateur constructor, voltages and current capability become very serious business
Other aspects of the design also change, such as increased driver capability required to drive large numbers of output pairs and remain within their SOA
Protection becomes more critical and needs to be very robust

I'm sure the list goes on but I think the picture becomes clear. Yes, we do sometimes see absurd designs from time to time. No, they are not practical nor even reasonable. The Slew series designer had some very valid reasoning for his decisions on the SlewMonster OPS design outlined in the development thread.

 

[evanc]

For home use I can't imagine needing more power then the 5 pair slewmaster can deliver.
If you need more power for party use and ******* off the neighbors a block or more away buy a used crown or qsc pa amp.

 

[rhythmsandy]

Its not for loudness.
It gives more control over the cone?
lower output impedance?
lower bias per transistor though.
Agree the cost factor but take an example passlabs the way they use the number of output stages? 76!!!!

 

[jwilhelm]

The bias per transistor would remain the same. Pass labs amps are class A, that's a whole different ball game. If you want more output, it's likely better to just choose some different output devices. MT-200 Sanken devices or some Exicon products can increase 5 pair output power handling to ridiculous levels.

 

[rhythmsandy]

The bias per transistor would remain the same. Pass labs amps are class A, that's a whole different ball game. If you want more output, it's likely better to just choose some different output devices. MT-200 Sanken devices or some Exicon products can increase 5 pair output power handling to ridiculous levels.

Im currently using double die Exicon mosfets with 250W package.

Its not power like I said isnt it for lower distortion? well control over the bass driver?

 

[jwilhelm]

Im currently using double die Exicon mosfets with 250W package.

Its not power like I said isnt it for lower distortion? well control over the bass driver?

Both objectives are pretty much the same in output stage design. If you want to control the driver better, you need to be able to move current easier.