Panzer, a new Dx Amplifier maybe born next months

[destroyer X]

I am already buiding, simulating and tweaking.

I am using NAD3220 as reference... the starting point..the topology to be tweaked, modified and tested to see will be released or not.

As people is trying some nice conversations about into the Precision Thread and into the Dx Amplifier thread, i have opened this one to make people free to talk whatever folks wants to coment about.

I have researched a lot.... about everything published into our forum, into Reviews, Magazines Reviews, Test Reviews, schematics and also into the Google.... everything was readed.

Now i have something built and sounding.... 24 hours playing and already received several modifications..... i am not happy with the sonics i am listening today...will work to make it better.... or, at least will try.

Mufled..strange trebles.... a little bit boomy.

Nice sound stage, focus and reasonable presence of mids.... dinamics interesting but saturates very easy as do not use Differential amplifier into the input.

regards,

Carlos

[destroyer X]

Was assembled, exists in real life.

40 volts for a while, and difference supplies to the input are unders test.... Output is around 125 watts..... well.... this is the start of the whole thing.... the power decision is for the future.

regards,

Carlos

[destroyer X]

Maybe will be unrecognizable in a month.

I am trying ideas, and listening to them.

I will not try ALL ideas people is offering, but i may try some....no guarantee to try ideas posted.... so, put them here because your own will...no deal made!

Carlos

[Nordic]

Tried makeing a powerfull HRII?

[MaxS]

Hello all,

Carlos is not trying to make a kind of powerfull HR II, he'll try to get his big brother or his fat cousin, at least.

Using some new ideas to make some new amps. This is just a way to get fun à la manière de Carlos. Nothing more, nothing less.

We are justing after your measurement, hum, feelings.

Panzer DX, the one who needs a fan around twice than the roomsize !

Max

[Nordic]

heheh, I can't help it, I love HRII!!!!!!!!!!!!!

[destroyer X]

You have made a lot...you can ask the Dx Corporation retirement that will turn you a very precious and important counselor.

Dx Standard, HRII and Precision I is past.... now going to the future.

a la manière du Charles!... some audio challenges.... some curiosity to kill, some strange designs to listen too... fun!... 100 percent pure fun!

It is beeing interesting... this amplifier was so famous, and now i am understanding the reasons... why people like it so much.

Vive la France!

á bientôt

Charles

[destroyer X]

Because they are hundreds.... many folks have ideas, have no time to build or have no will to build....so... those may run to me if i offer to test everything.

I am in the third stage of my audiophile evolution.... first stage was to build everything and listen and test, and compare with something.

Second stage was to design, to make mine since the early beginning..just selecting one topology and the most used voltage....to make my own.

Third stage, the one i am starting now... alike Japanese did into the sixties...and Chinese doing rigth now.... selecting good international designs, testing them and tweaking them...so... a big save, enormous economy of time... have not the time of development and not the costs of development....just select one good and tweak...some small modification can make, even better, already famous and well known designs.

I am in this level...interested to famous ones.... the ones sell hundreds, or thousands or million of units...to listen those ones, to copy those ones and to tweak those ones (or try) for sonics.

If i have opened to build any schematic folks have produced, i would turn crazy with that..so many would come.... creative folks sit in from of the computer, and produces 100 schematics a day..and they build no one.

regards,

Carlos

[homemodder]

Hi Carlos,
Tudo bem contigo??

For this circuit i suggest use a cfp as input transistor. There is a good criteria on how you should select the two trannies for best linearity but it will be too long for me to explain here. Ill make a copy of a document i have and send it to your mail. There is also other info regarding cfp pairs - regarding transconduction harmonic signiture and comparing their use against single trannies and jfets in ltp stages.
Maybe these things were covered in dr Selfs book, i dont know havent read it. This was by someone else but i cannot recall the name now.
By the way i like the sound of jfets, how about one here on input????

Good luck with this circuit, twenty years ago they sounded ok to me, but very inferior to a JLH amp i bought as a kit to build when i was a teenager..... no not the famous JLH class a Amp, a 100 watt A/AB i think it was. Also built a JLH pre-amp, to think of it it very much miss that preamp, it was glorious. Nordic lives out that way, maybe i should contact him and see if the shop i bought those kits still exists.

Carlos have you tried cascoded current mirror on P1 Ltp. These have two main benefits sound wise :
Two transistor mirrors tend to compress the sound and even using very large hfe trannies doesnt help that much, this does.
Brings the Ltp collector currents closer to balance which not only drops the distortion (2nd but also 3rd and higher harmonics too) but is also essential in obtaining good precise sounstage in this topology.
For all the other EEs here, yes their are other benefits, but lets keep this simple and more related to the sound than the electronic theories.

Alex

[destroyer X]

Will answer you a little bit latter.... very busy now.

Thank you.

Estou um pouco enrolado agora...com mais calma conversaremos

Saudações

Carlos