Dx TriAmp bass unit

[destroyer X]

I willl modify, very soon, a Dx Amplifier Standard to work with 90 plus 90 volts..it will be modified and prepared to work as a sub amplifier to a three amplifiers system..three amplifiers to each channel.

All them will be Dx amplifier customized, because simple, cheap and reliable.

This is just the first thougth using simulator..you see that the "frame"..the basic amplifier is the standard..nothing special on that..only the feedback capacitors and some adjustments.

This was not assembled..but it will be, and very soon, and for sure will work fine..adjustments and modifications may be made, including an input filter.

Power goes to 780 watts RMS into 4 ohms easy..distortion is high into 200 hertz... for a while, full power goes to 1 percent, and i will reduce that soon.

The amplifier will operate from 1 cicle to 300 cicles.... loosing almost 3 decibels into 300 cicles...the mid unit will start into 300 cicles and -3dB too.

All them will be made using Dx standard.... midrange will operate with 50 volts and treble will operate from 25 volts simetrical separated supplies...one supply to each amplifier...three supplies each channel.

Input will have passive filters and volume pots.

This way you will not worry, anymore, with speaker ballance, also room acoustics....you will need to run a cable from the speaker... 6 wires... one pait to bass, other pair to midranges and the third pair to the tweeter.

Thank you Dudainc to stimulate me to do this way..for a while passive, but Duda wants active.... will do that also.... for the future.

This one was not assembled...it is a son of a simulator...do not assemble for a while..let me debug.... those things into simulator sometimes results not fine...wait a little, please.

Transistors are the ones i have.... the input does not need big transistors, of course....those are the ones i have to work with high voltage...will try others too.

Into 8 ohms, around 435 watts RMS into the threshold of clipping...but this depends on the supply.... bad supply will turn that 200 watts or even less..all depends on the supply power..good supply results good power..bad supply results weak continuous results and interesting peak results.

regards,

Carlos

[destroyer X]

I have two more, home made, home etched, to the mids and highs.

regards,

Carlos

[pacificblue]

Your neighbors will become very happy. They won't need a stereo of their own any more.

Do you have a woofer that can withstand so much power and convert all of it into sound pressure?

[wg_ski]

Originally Posted by destroyer X

This one was not assembled...it is a son of a simulator...do not assemble for a while..let me debug.... those things into simulator sometimes results not fine...wait a little, please.

Transistors are the ones i have.... the input does not need big transistors, of course....those are the ones i have to work with high voltage...will try others too.

Go ahead and try a small signal transistor model in the input stage - the simulator doesn't care if you run it past its ratings. That will give you better distortion numbers, and a better simulation than using a model for a part that doesn't have anywhere near the right characteristics. I'm sure you can find something suitable in your parts stash somewhere when you go to build it. MPSA92?

I've never seen an LTP using MJ15023's - but I have seen them used in a VAS. It was in a 300 watt Gallien-Kreuger bass guitar amp.

[wg_ski]

Originally Posted by pacificblue

Do you have a woofer that can withstand so much power and convert all of it into sound pressure?

Two words: head room. Carlos probably got tired of seeing his amps clip on the o-scope when it's not all *that* loud.

And nobody has a woofer that converts it *all* to sound pressure. The best you can hope for is about half (and that's for a horn).

[pacificblue]

Originally Posted by wg_ski

Carlos probably got tired of seeing his amps clip

No way! Carlos started a thread called "What they love to listen..... distortions!"

[destroyer X]

When starts to clip, people smile and say..."yeah!...loud!"

hehehehehe.

I have one speaker that can hold all that power... at least can hold the volts and amperes.... i do not know how much will distort when receiving high power levels...the coil can hold all that power...i do not know how will perform.....i am pumping 150 watts now a days and it is asking for more.... we gonna know how will perform with 400 watts and more (8 ohms).

Problem here is to find capacitors to face all that voltage...the supply voltage is very high to my capacitors and electrolitic condensers....for a while i will have to arrange some of them in series, to face more voltage...but this is for s while, as Sakis has send me huge ones that may arrive in November...they are with Dudainc..he may travel to Brazil soon..if not November will be Christmas.

I have no small transistors to that voltage...i will have to use those folks...at least to start some test.... this will not impeach me to do something..if not with the perfect parts will be with non perfect parts for a while.

I will move my ..., will do something...bye folks!

regards,

Carlos

[ostripper]

That 550w woofer there would become toast with a true 300watt amp , much less a 500w+ one ! With twice the magnet and twice the voice coil , a real subwoofer ...
http://www.parts-express.com/pe/psho...08&ctab=1#Tabs

will "tap" (bottom out ) even in a sealed enclosure at 300w. I know you don't like leach amps or triple outputs , Carlos .. but for subwoofer purposes and a woofer that will occasionally require 2 ohm loads , it is the only way.

(attached below) is the "standard" for all 3 of my amps , I have driven it (different voltage stages)with DX type amps , symasym , self amps ... it does not matter. It will bottom out any woofer out there , including this one ..
http://www.parts-express.com/pe/show...number=293-620


(that is with 24 NJW21193/4's as final OPS - 100v rails)
The main advantage to the triple is that IT does all the work , leaving the input/voltage stage alone (much lower distortion). With 70-100v rails , you have nothing to lose with a triple (2 extra Vbe's).
OS

[destroyer X]

Today i am feeling lazy...i have prepared the amplifier only...tomorrow i will check and put it to work.

Condensers are in parallel...i have no high voltage ones....the input is MJE15032, also the VAS is the same...the driver is a 100 watts Sanken...nice ones..and the output is under the board.... they are 2SC5200 and 2SA1943... small amplifier using this board..reason why i revert everything to the Dx Standard and make some tweakings into frequencies and currents.

Gonna see them toast (test) tomorrow.

regards,

Carlos

[ostripper]

Gonna see them toast (test) tomorrow.

Really , I did not make fun of the woofer. they do it here , too ... pyle subs and other name brands geared toward the "enthusiast" lie about power ratings all the time. Inside of the woofer.. If it has a 2"-2 1/2" coil , most likely 200w+ will "toast it" 3-4 " coils will do a REAL 300w+. Even with a big coil , in a ported box , the woofer will handle far less wattage than in a sealed one.

Another way to tell if there is truth is the cost $$$ ... the peerless cost 150US $ and the german one (audiopulse- 1KWatt) is $649 .
OS