MPP

Hi Benedetto
You are quite right Euro card standard is 100 X 160

In my case the transformer enclosure is 220 mm long I should have stressed that.

It will be possible to shrink the board a bit as there is load of space especialy on the Electrolitic / output end.

I am open to any suggestion and make any changes as needed.
Last exercise was to see what can be done, nothing definitive.
 
I had a Paradise PCB with me but i am not finished with stuffing. Hesener is in the US so we could not play it.
A lot of combinations of equipment was playing. I was a bit late and had a lot of talking so i can only comment on the system we put together at the end of the day. Frans and i had setup Frans phonostage. He had brought the MM version so for MC we needed a prepre.
We used the original build of the Ultra Low Noise Rosi. That is a more then 2 years old prototype. First we listened to a Swiss Holbourne table and then we switched to a Loricraft-Garrard 401 with Naim Aro arm and Lyra Scala. The preamp was by Sam build after a circuit i designed with a PSU from Klaus. Amps where modifies SymAsym with tubes in the input differential stage by Jim Tonic. The loudspeakers where Klang und Ton
Nada. See the picture of this speakers at ETF2011.
 
The sound we got was really good. I was very happy with the speakers and that is rare.
They where uncolored and surprising dynamic though this is a 85dB 25 Liters closed box design. They had no problem to fill the room with more then sufficient volume.
I had played around with the Scan Beryllium dome before but this was the first time i heard it over many hours on a great system. I heard rumors that some find it sharp and other dark but in this implementation it sounded perfect. There was a very "quiet" quality about it. Treble sounds only appeared when they where on the record. This tweeter does not draw any attention to itself. Treble instruments like cymbals had a unique robustness and plasticity. I was very easy to differentiate the tonal color between a Vibraphone and a Xylophone for example. I tell you more soon.
 
Here is a picture of the NADA at ETF2011.
The front plate is from massive oak and the cabinet is well braced and damped.
You can see metal rods.
 

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Hi guys,
has anybody from beta builders already tested riaa error on their builds ? Today I finally had some time to sort my bjt's so in order to not get bored to death, I've put paradise circuit to multisim. I used latest schematic from hesener. Everything seems to be as advertised (more or less), and I give my hats of to MiiB, for that auto biasing part using mirrors and ccs, really clever ;) It's just that I get quite large riaa error. This could be only due to different model's/software, as I'm using proven laplace polynomial coefficients for bode plotter, so I tried couple other 337/327 models from net, but results were about the same as with multisim's build in ones. Theoretically for 53.5k output impedance it should be 7.78k+40.8nF/14nF, so 7.5k is really low, and 13.6nF with 200Ohm will give that nasty peak at 20k+, I would put 10+3.9nF there. Just my 2 cents.
 

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Here is the official schematic.
Do i miss something here ? I can not see the 200 Ohm resistor.
No, i do not think that anybody has measured a working Paradise. The only one that is playing is the one that Hesener has and he is on a busyness trip. MiiB promised plus-minus 0.3dB and i already discussed with Ricardo that we will trim the circuit after we have measured the actual build. It can actually be that your calculation is more accurate. But please simulate first the official circuit too that is attached.
How is the balanced Starless going ? Have you put more work into it ?
 

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  • Paradise MPP 2012 official schematic 29.1.2012.pdf
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Hi guys,
has anybody from beta builders already tested riaa error on their builds ? Today I finally had some time to sort my bjt's so in order to not get bored to death, I've put paradise circuit to multisim. I used latest schematic from hesener. Everything seems to be as advertised (more or less), and I give my hats of to MiiB, for that auto biasing part using mirrors and ccs, really clever ;) It's just that I get quite large riaa error. This could be only due to different model's/software, as I'm using proven laplace polynomial coefficients for bode plotter, so I tried couple other 337/327 models from net, but results were about the same as with multisim's build in ones. Theoretically for 53.5k output impedance it should be 7.78k+40.8nF/14nF, so 7.5k is really low, and 13.6nF with 200Ohm will give that nasty peak at 20k+, I would put 10+3.9nF there. Just my 2 cents.

Hi Sampler... I am not using the 200 ohms esistor but my calculations point me to similar conclusions.

7.796kr + 40.78nF / 13.99nF would be perfect.... Instead of using 15k // 15k I would use 15k // 16.2k = 7.793kr

My half cent

Anyway, I agreed to build it as is and listen for a while before making any adjustments.

PS:
I have a psu with two independent bridges and smoothers that output 40Vdc... each... is that too much to feed the +- Vraw in the paradise ?
 
For those of you who wanna have a glimpse at what has taken place at the Frickelfest light: Endspiel
You may also spot our ATL contact guy Frans ;).
Was a pleasure to meet you, Frans, hope to see you again.
And I have to agree to Joachim: We had a really fantatstic sound. Apart from that, it was great fun and lots of interesting people.
Great warm up for the big Frickelfest in June.