Just take the Spice file and replace the TTA004 with those.
BC327 is standard device in LT spice.
Play with the drain resistor values to change bias.
You will find that distortion goes down with more bias.
But dissipation goes up. So there is a balance somewhere.
But you can always use multiple BC327s in parallel to increase bias.
600R (of the transformer) is not exactly a light load.
Patrick
BC327 is standard device in LT spice.
Play with the drain resistor values to change bias.
You will find that distortion goes down with more bias.
But dissipation goes up. So there is a balance somewhere.
But you can always use multiple BC327s in parallel to increase bias.
600R (of the transformer) is not exactly a light load.
Patrick
IPS6 - boards stuffed
Hello M2X-builders,
I've got the rest of my parts for the IPS 6 - boards. Stuffed them yesterday.
Some adjusting - first on my 'test-rig' than in the amp.....
No listening yet - I can't tell you how it sounds.....
later
Thanks to Mark Johnson for a new inputboard!
Thanks to Ake for the group buy of the pcbs!
Greets
Dirk
Hello M2X-builders,
I've got the rest of my parts for the IPS 6 - boards. Stuffed them yesterday.
Some adjusting - first on my 'test-rig' than in the amp.....
No listening yet - I can't tell you how it sounds.....
later Thanks to Mark Johnson for a new inputboard!
Thanks to Ake for the group buy of the pcbs!
Greets
Dirk
Attachments
Black Forest Buffer Proto
I was curious myself how this would work in reality.
So a quick & dirty Vero proto using what I had in the drawer.
The bandwidth is way beyond 2MHz (my spectrum analyser limit).
But it is also very good at picking up HF noise, from LED lamps, laptop SMPS, ..., etc.
So I put in an RF filter at the input, and also two caps at the BJT to enhance stability.
The schematics attached is as built, with 30mA bias.
Also attached frequency response, 100kHz sine, triangle and square, after all the above measures.
QED,
Patrick
.
I was curious myself how this would work in reality.
So a quick & dirty Vero proto using what I had in the drawer.
The bandwidth is way beyond 2MHz (my spectrum analyser limit).
But it is also very good at picking up HF noise, from LED lamps, laptop SMPS, ..., etc.
So I put in an RF filter at the input, and also two caps at the BJT to enhance stability.
The schematics attached is as built, with 30mA bias.
Also attached frequency response, 100kHz sine, triangle and square, after all the above measures.
QED,
Patrick
.
Attachments
Hello M2X-builders,
I've got the rest of my parts for the IPS 6 - boards. Stuffed them yesterday.
Some adjusting - first on my 'test-rig' than in the amp.....
No listening yet - I can't tell you how it sounds.....
That enclosure looks phenomenal!
Could you post some more pics?
Last edited:
Thanks, looks fantastic.
I see you setup a switch for the input cards. That's very cool! It takes me ~1h to change out the cards...
That’s a really neat idea. Food for thought for the next one I build. First one i just finished was destined for the living room but is still in my office/workshop/spare bedroom and I’m loving it so much I’m not letting it go.
Ditto
I think these are netlists for simulations.
Based on the measurements the performance appears to be stellar. it would be nice if there was a more practical or 'buildable' description, at least for me.
+/-24V Rails ?
I was asked whether the BFB can take +/-24V supply directly.
In principle yes.
The 2SK117/2Sk209 are rated at 50V.
The TTA004B even at 160V.
But the limit is the dissipation.
The TTA004 is rated 1W in 50°C air without heatsink.
So 24V 30mA is still OK with a small heatsink.
But the 2SK209 is only rated at 150mW at 25°C.
And not everyone has 2Sk117GRs.
Also, the rails for the power stage are probably not particularly low noise / low ripple.
So it is still better to regulate locally down to +/-12V.
This is how I would make a simple shunt reg, using also the TTA004.
The Vf of the LED will vary, so you will need to trim Rs3.
I have not tested, so build at own risk.
Patrick
.
I was asked whether the BFB can take +/-24V supply directly.
In principle yes.
The 2SK117/2Sk209 are rated at 50V.
The TTA004B even at 160V.
But the limit is the dissipation.
The TTA004 is rated 1W in 50°C air without heatsink.
So 24V 30mA is still OK with a small heatsink.
But the 2SK209 is only rated at 150mW at 25°C.
And not everyone has 2Sk117GRs.
Also, the rails for the power stage are probably not particularly low noise / low ripple.
So it is still better to regulate locally down to +/-12V.
This is how I would make a simple shunt reg, using also the TTA004.
The Vf of the LED will vary, so you will need to trim Rs3.
I have not tested, so build at own risk.
Patrick
.