REAL 2 Ohm, 10KW Amplifier

Hello Guys,

Thank you for the warm welcome here. Seems I found the right place to be. Glad to meet all of you here.

Here it is, "THE KILLER MACHINE"
A 10KW Heavyweight Amplifier meant for serious 2 ohms driving capability. Utilizing a Dual High Efficiency Toroidal transformers coupled with a total of 32 pcs. high storage capacitors
3 Steps Predictive Rail Switching MOSFET Class H with a combination of Grounded Emitter Topology comprising of 24 Output Devices per Channel

Well done Xmax, smiley32

What happened to your pics on the SP amp internal thread?

What are the main differences between yours and the Inf8Mk2?

www.speakerplans.com/inf8is1.jpg

levyte357 wrote: Well done Xmax, smiley32

Didn't you put these pics up in the Amp Internals Thread on SP? What happened to them?

Hi Ray,

Yeah, but you were right on the first place, those were deleted also by the mods... smiley5

Cheers
Max

What are the main differences between yours and the Inf8Mk2

Hello Ray,

There are key main differences between these 2 amplifiers:-
1. Alpha has DUAL MONO SUPPLY, i.e. 2 Transformers , INF8 has only one transformer
2. Alpha has ample Capacitance, 36 pieces of 15000MFD/65V each , INF8 has no more than 12 capacitors.
3. Alpha has 12 Pairs of Transistors for output, INF8 has 8 Pairs for output.
4. Alpha uses High Current MOSFETS + SoftRecovery Commutation Diodes in TO-247 Package[Bigger Silicon and dissipation area] in its 3-Step rail Switching Class-H mechanism, INF8 uses TO-220 small packages devices.
5. Alpha uses Transverse Cooling which keeps all transistors in output stage at same thermal gradient, INF8 uses tunnel cooling which causes the devices to have variable thermal gradient along the length of Heatsink.

Apart from this, Alpha is not current limited in anyway with loads as brutal as 1 Ohms, it does have a short circuit protection working at less than one ohm loads for reliability. You can feed a 20khz Sinewave till clipping into the amplifier with 2ohms load connected to it, it will not fail electrically, only thermal tripping will occur due to steep temperature rise because of nature of signal, with music loads you can pump up without any thermal tripping in 2 Ohms loads through out the day with ambient ranging to 35C.

Its only disadvantage is its weight 52kgs because of dual mono Linear supply and linear class-H output stage with big Heatsink.



regards,
Kanwar
Zypher Labs

I thought that the amp had 32 caps as stated by xmax. No matter though 36 is better!!!!! The only thing is having the bridge sitting on top of the caps or is it seperated from the tops of the caps?

NITZ V1505 wrote: I thought that the amp had 32 caps as stated by xmax. No matter though 36 is better!!!!! The only thing is having the bridge sitting on top of the caps or is it separated from the tops of the caps?

Hi,

It has 3 rows of 12 caps each so 12 X 3 =36 caps, The PCB you see at the top of caps is for low power separate housekeeping supply only. The supply has 6 Bridge rectifiers mounted under 'U' Bracket. smiley1 .

Kanwar

Kanwar, "I think" you mentioned something previously about why more smoothing, transistors, transformer capacity is needed to support driving low impedance reactive loads in real life vs purely resistive loads on test bench...

What was that?

EDIT:Did you also mention manufacturer recommended transistor count per channel, for TO-220 for specific output power ?

levyte357 wrote: Kanwar, "I think" you mentioned something previously about why more smoothing, transistors, transformer capacity is needed to support driving low impedance reactive loads vs purely resistive loads on test bench...

What was that? ( Think it was deleted from somewhere, for some reason...)

smiley36 Yeah, That was on SP, it was posted by Karav. It was not only deleted, but he was banned also.

Driving reactive loads, puts great stress on the output stage and power supply, because the current waveform doesn't follows voltage waveform in synchronize manner like in resistive loads. Sometimes amplifier is forced to supply the current even when the voltage is on zero crossings and phase shift as deadly as 60degrees. It happens when driving real world speakers and more often when driving speakers which incorporate passive x-overs in them. This type of loading requires the output stage with more parallel pairs to keep the devices well within its SOA and power supply with higher reserve capacity.

Kanwar

levyte357 wrote: EDIT:Did you also mention manufacturer recommended transistor count per channel, for TO-220 for specific output power ?

If we look at Max allowable continuous current rating of TO-220 package pins, its not more than 35A [Provided IDS rating of silicon is well above this limit]

Compare the same with TO-247 package used in ALpha, it has MAX continuous of 75A limited by pins.

For an amplifier delivering 4KW into 2 ohms, it has to provide 45A in to the load in continuous manner, and peak current into resistive loads is around 65amperes, One can simply conclude that noway one can use TO-220 package for such a hefty rating, one has to opt for higher rating Package also.

And "SIZE DOES MATTERS" atleast when driving continuous 2 Ohms smiley20

Kanwar

Kanwar wrote:

levyte357 wrote: EDIT:Did you also mention manufacturer recommended transistor count per channel, for TO-220 for specific output power ?

If we look at Max allowable continuous current rating of TO-220 package pins, its not more than 35A [Provided IDS rating of silicon is well above this limit]

So how many TO-220 would be needed by an amp, according to transistor manufacturer specs, to stably achieve 2.5k, 3.7k wpc @ 2 ohms into reactive loads?