This speaks for itself:
https://www.diyaudio.com/forums/multi...ml#post2318365

My job at the garage has been reduced to 4 days a week, which is great as it means I have an nice long weekend break. With all the free time I'm going to be working on my custom car stereo system.

My Nissan Micra probabaly doesn't have the best speaker system around.. Which is just as well because I'm going to upgrade it!!

I'm going to break open my old PC speaker sytsem



And install it in my car. The sound qouality is amazing and I'm sure I'm going to get a lot of enjoyment out of it too.

Nelson has created a storm of interest with the Zen I/V.

I have a DAC that I can use this with, a K&K RAKK DAC Mk1.

Currently, it has a passive supply and a switchable shunt resistor.

So I am brainstorming on what it would take for an active Zen I/V with a shunt volume control, and both SE and Balanced outputs.

Basics: PCM1794 has differential outputs with 8 ma current output.
https://focus.ti.com/lit/ds/symlink/pcm1794.pdf
So I need 2 Zen I/V per channel.
At present, I am running a DCX2496 Digital crossover, so balanced outputs are a plus.

I am considering using the buffer from this post.
Since bipolar supplies are required for the I/V section, a buffer that does not require additional caps seems prudent.

For the volume control, either https://www.kandkaudio.com/linestage.html Shunt Stepped attenuator or a single LDR replacing the K&K unit.

Finally,...

Hi to everyone!!!

I'm new i this site
I just want to ask for some pcb and schematic for a 200watts amplifier

Can P3A amplifier from ESP modified?
and add some more output tannies?
maybe 3 pairs?

I want to use MJE2955 and MJE3055 for the outputs.....

Any body?

In the earlier post, basic common emitter amplifier design, I made reference to increasing the gain of the amplifier by bypassing the emitter resistor R[SIZE="1"]E[/SIZE].

In this case the gain referred to is the AC gain, which is the signal gain, and which is the gain we are primarily interested in with regard to audio amplifiers. The gain previously calculated was the DC gain, which was numerically identical to the AC gain, but since the amplifier was decoupled from the preceding stage with a capacitor, there was no DC applied to the transistor other than that provided by the bias network, which set the standing current to 1mA and the output voltage to 10V. DC gain and offset is important, because a decoupling cap can be avoided in some cases, but not here.

In the earlier post the gain was stated to be –R[SIZE="1"]C[/SIZE]/R[SIZE="1"]E[/SIZE]. This was a simplification, and, more strictly the gain is –R[SIZE="1"]C[/SIZE]/(R[SIZE="1"]E[/SIZE]...

This is my first serious amp project. It uses the IRFP9240 & IRFP240 MOSFETs and delivers 100WRMS into 8Ω or 160WRMS into 4Ω at 0.1% THD.

Many thanks go to Edwin Paij @ AED (https://users.swing.be/edwinpaij/welcome.htm) for the design .

I have now gathered the majority of components and am currently active in the forum looking into PSU design...

Hey, I've got my Technics SL-3 turntable power supply damaged by a high voltage burst from the power station. I've found out that the transformator is damaged, but I haven't been able to find a new one. The number on it is SLT48DT 15E. I need to know either where to buy a new transformator or what specifications (voltage 240/? . .) this transformator has. Anyone who can help me solve this problem?

This is an implementation of National's reference design for LME49830 with two matched pairs of 2SK1530+2SJ201 per channel. The PCBs were made using National's gerbers (thus National's logos). Sounds surpisingly good, but it has just been completed; I did not have a chance to listen to it carefully yet.

Update: I rebuilt the amp as a pair of monoblocks, each delivering healthy 200W into 8 ohms. It now looks tidier.

Update: the original Gerbers from National are nowhere to be found since national.com was merged into ti.com. Attached are the original archives downloaded from the national.com.

This was unavoidable, I guess. Dual mono LM3886 kit from ChipAmp.com with Avel Lindberg's transformers in a wonderfully compact enclosure from Design Build Listen. I liked the simplicity but not the sound. Why is everyone so excited with gainclones? IMHO, Papa's Zen V4 is not much more complicated to build (although no kit is available), but is so much more an interesting experience!

Last year I got an Lm60 kit from AmpsLAB. This year, I finally got an enclosure from Design Build Listen and a power supply and built it. Each channel is built on a small (120x60mm) one-sided PCB and uses one 2SK1058+2SJ162 pair in the output stage. With proper biasing, the sound is good, esp. for such a simple and compact design. I should have started with this one, rather than with the (equally inexpensive) K-8LS.