Redesign 544: „Rev/One 2018“

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Peter B.
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Lid geworden op: ma 22 sep, 2014 15:38 pm

Redesign 544: „Rev/One 2018“

Bericht door Peter B. »

Sehr geehrten Kollegen,

hiermit beginne ich hier die Redesign-Arbeit „Rev/One 2018“, mit allem was bis heute geleistet wurde, zu präsentieren. Das Projekt umfasst vier PCBs. Die ersten beiden (Eingang und Service) sind fertig. Die Arbeit an der dritte Leiterplatte (LP3) beginnt in Kwartaal Woche 2 (KW2). Das gesamt Konzept unterscheidet sich nicht wesentlich von herkömmlichen Standard-Schaltungslösungen. Ich denke, es ist wichtig Gedanken, Informationen und Pläne über diese LP3 auszutauschen. Siе ist diе wichtigste in diesem "Rev/One 2018" Redesign. Das größte Problem hier bleibt den Netztransformator und seine einzige Sekundärwicklung. Der sollte nicht durch einen anderen Ringkerntransformator ersetzt werden. Eine weitere Bedingung war, dass es keine wesentlichen Änderungen in der Konstruktion geben sollte. Alle diesen die mit der Bearbeitung - Bohren und Schneiden - verbunden sind. Trotz Einschränkungen ist es möglich, einige Kompromisslösungen zu finden. Sowohl in der Mechanik als auch in der Elektronik.

Daher werde ich nach Abschluss der Arbeiten an diesem Board und der Bestellung der ersten Leiterplatten ein neues Projekt darauf aufbauen. Neu wird im Wesentlichen nur LP3 und der Verwendung einen neuen Ringkerntransformator. In diesem neuen Satz Mk3 von Leiterplatten ist nur LP3 neu. Die Schaltung umfasst drei Stromverstärker-Endstufen (Current drive Verstärker). Der Bass-Kanal wird wieder mit MFB funktionieren. Aber für die mittleren und hohen Frequenzen wird eine Stromrückkopplung in der Endstufen als eine Art Strom-MFB eingesetzt. Das neue Design kann sowohl mit den RH544 als auch mit den brandneuen Drei-Band-Boxen verwendet werden. Das aber bleib erst nur als Zukunftsmusik.

BLOCKSCHALTBILD „REV/ONE 2018“
Das Blockschaltbild „BSB RevisionOne 544-2018“ ist auf Abb.1 zu sehen. Die ersten beiden Leiterplatten - LP1 und LP2 sind jeweils "Input Module" und "Service Module". Die dritte PCB (LP3) ist die Hauptkomponente für den gesamten Niederfrequenzteil des RH544-Lautsprecherboxses. Sie enthält die folgenden Blöcke (Abb.2):
- Frequenzweiche-Filter für drei Endstufen,
- MFB,
- Begrenzer (Limiter) - Schutzschaltung,
- Endstufen,
- Stromversorgung: +/- 15V, Stromversorgung der Endstufen.
- "Knotenpunkt" der einzelnen GNDs.
- Übergangschematik von "GNDs-Knotenpunkt" zu Chassis – auf Mini LP4.
BSB Abb.1.pdf
Inhalt LP3 Abb.2.pdf
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rob040
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Berichten: 192
Lid geworden op: vr 07 nov, 2014 16:01 pm

Re: Redesign 544: „Rev/One 2018“

Bericht door rob040 »

Dear Peter,

This might be interesting, but since I don't speak/read German for me it's hard to follow. Is it possible to post in English? What do other members think of that? Or am I the only one who has this problem?

All the best for 2018 to everyone!

Regards, Rob.
Laatst gewijzigd door rob040 op za 06 jan, 2018 11:43 am, 1 keer totaal gewijzigd.
Mijn PCB's zijn groen, dat is mijn bijdrage aan het milieu.
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motoindo
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Re: Redesign 544: „Rev/One 2018“

Bericht door motoindo »

Google translate ?

Overigens kan er gewoon in het Nederlands gereageerd worden.
Chris Camphuisen
mfb does to the ear what a pretty face does to the eye
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Sandrowski
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Lid geworden op: ma 27 apr, 2015 13:03 pm
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Re: Redesign 544: „Rev/One 2018“

Bericht door Sandrowski »

Interessant! Helaas een beetje te laat voor mij (de 544MkII is net af), maar ik ben erg benieuwd hoe dit er uiteindelijk uit gaat zien.

Als de bestaande transformator behouden blijft, wat voor soort versterkers worden er gebruikt? Single-ended met uitgangselko of brugversterkers? Bij een brugversterker ben ik erg benieuwd naar de implementatie van 'current drive'.

De oplossing met 4 printen is trouwens niet compatibel met de 544/50. Ik neem aan dat de ekomatic op het geïntegreerde stopcontact moet komen, maar die ontbreekt op de 544/50. Geen onoverkomelijk probleem natuurlijk, maar voor die versie van de 544 zal er dan toch geboord moeten worden.

Groet,
Sander
Groet,
Sander
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motoindo
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Re: Redesign 544: „Rev/One 2018“

Bericht door motoindo »

Sandrowski schreef:Interessant! Helaas een beetje te laat voor mij (de 544MkII is net af), maar ik ben erg benieuwd hoe dit er uiteindelijk uit gaat zien.
Ik ben zelf ook erg benieuwd naar Peter zijn werk, vooral de ontwikkelingen rondom de ingangsprint is iets waar ik naar uitkijk.
Chris Camphuisen
mfb does to the ear what a pretty face does to the eye
Peter B.
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Lid geworden op: ma 22 sep, 2014 15:38 pm

Re: Redesign 544: „Rev/One 2018“

Bericht door Peter B. »

I apologize for the late correction from German to English. Here's the translation:

Dear colleagues,
I am going to present the work, that is done so far. The project covers three PCBs, and another very small circuit board for grounding the chassis. The first two (Input and Service) are ready. And the third one starts after KW2. The concept is not much different than standard circuit solutions. I think it is important to exchange thoughts, information and schemes about this LP3. It is the most important in this "Rev / One 2018" redesign. The most serious problem with this variant is the power transformer and it´s only secondary winding. It should not be replaced with another toroidal transformer. A second condition is that there are no major changes in the design associated with machining - drilling and cutting. Despite these constraints, it is possible to find compromise solutions. Both in mechanics and electronics.
Note: Therefore, after finishing work on this board and ordering the first PCBs, I will start a new project based on this. In this new set of PCBs, there will be new LP3 and there will also be a new toroidal transformer. The circuit encompasses three current amplifiers. The low-end channel will be with piezo MFB as it is now. The other two channels - medium and high frequencies - will be with the current MFB. The new design is made for brand new tri-band boxes.

1. BLOCK DIAGRAM "REV / ONE 2018"
The block diagram "BSB RevisionOne 544-2018" can be seen in Fig.1. The first two PCBs - LP1 and LP2 are respectively "Input Module" and "Service Module". The third PCB (LP3) is the main component for the entire low frequency section of the RH544 speaker box. It contains the following blocks (Fig.2):
- Three channel crossover filter,
- MFB unit,
- Limiter - protection circuit,
- Power amplifiers,
- Power supply: +/- 15V and power supply of the power amplifiers.
- "Node" of the individual GNDs.
- Transition scheme from "GNDs node" to chassis - on Mini LP4.
Peter B.
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Lid geworden op: ma 22 sep, 2014 15:38 pm

Re: Redesign 544: „Rev/One 2018“

Bericht door Peter B. »

2. PCB 1
In the first place, I present you the LP1. The scheme is shown in Fig.3. It contains three block groups:
• Input - optional with DIN or RCA RCA jacks, input level attenuator and input channel selection (L or R), Subsonic filter with switch for two-frequency selection (Thank you, Hans for both MK2 designs!).
• Peak Display (+ 3dB) for the signal level after the first OP. Two LEDs are available as peak level indicator. An LED diode (D6) is mounted on this board next to the top edge of the PCB. Serves as an indicator when adjusting the input signal. It is only possible if the aluminum carrier plate is open. A second LED diode is mounted in place of the red "ON" LED in the front molding. The old LED is replaced by a new tri-color LED diode.
• Automatic - The third block is an automaton for switching on the electronics with an input signal. The scheme is by Chris - Ecomatic. Again, there are two LEDs for the status display "On" of the automatic. One is on the LP1 (D10) for service purposes and the second also uses the tri-color LED on the front molding.
• There is also another LED indicator on this board - D2 and D3. The LEDs visualize upcoming OP power supply (+/- 15V) supplied by the LP3. D7 (ECO) shows if the + 5V voltage is present.

A few words about a "novelty". I have switched a 2x6 switch (S1), which switches three input sensitivities: - 20Vrms, 7.5Vrms and 1.0Vrms for channel L and again for channel R. Switching takes place in 6 positions.

Again, one of the two potentiometers RH544 - R6/200k is in use. S1 and R6 are mounted on the same metal plate as (by) RH544. If any of you would like to use a new carrier then you can use the drawing in the documentation. Or I can help you with an order (made cheap by my company).
Before attaching and soldering the supporting pins of the metal plate, the two elements R6 and S1 must be mounted. The switch is pre-wired and there must be connected witch seven wires to LP1 connection areas: L, R, A, 1, 2, 3 and B. The wiring is shown in Fig.4.

The unbundling of the finished LP1 can be seen in Fig.5. Fig.5a shows top side = "assembly side" (BS) and Fig. 5b - bottom side = "solder side" (LS), Fig. 5c shows a 3D representation of the printed circuit board. The attached PDF file makes it possible to find the individual element on the LP.
The board itself has two groundings - AGND and PGND. These are implied on the printed circuit board as three polygons - Pol1-AGND, Pol2-AGND, Pol3-PGND. All three are connected at one point only - on both C12, C14 filter electrolytes. The polygons are shown separately in Fig.6.
Note: Some values of the components are not yet final. They can be additionally specified.
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rob040
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Berichten: 192
Lid geworden op: vr 07 nov, 2014 16:01 pm

Re: Redesign 544: „Rev/One 2018“

Bericht door rob040 »

Hi Peter,

Mooi werk, ik ben benieuwd naar het vervolg.
Waarom heb je gekozen voor een twee-traps ingangsverzwakker (schakelaar + potmeter)?

Groet, Rob.
Mijn PCB's zijn groen, dat is mijn bijdrage aan het milieu.
Peter B.
MfbLabs Gebruiker
Berichten: 68
Lid geworden op: ma 22 sep, 2014 15:38 pm

Re: Redesign 544: „Rev/One 2018“

Bericht door Peter B. »

Hi Rob,

The „Rеv/One 2018 project“ is designed for a wide range of owners of RH532, RH544 or RH567. Some of them can redesign the boxes themselves and remove the unnecessary S1, R6 (schakelaar + potmeter). They will have to make the changes themselves with new wires on the Pads line: L, R, A, 1, 2, 3 and B. Most people, however, will prefer to keep the old commands on the back (channel selection and level setting). With the help of the +3dB peak level indication, they will have the opportunity to optimally join a random (or another) signal source. Others would order a redesign at Piratelogic.nl or at the MFBfreaks, who opened an office recently. In both places everything can be done professionally! https://www.facebook.com/piratelogic/ph ... =3&theater

Groet, Peter.

PS -Tomorrow I will order 4 boards - two for me and two for Chris. Is there anyone else willing to test?
rob040
MfbLabs Gebruiker
Berichten: 192
Lid geworden op: vr 07 nov, 2014 16:01 pm

Re: Redesign 544: „Rev/One 2018“

Bericht door rob040 »

Hi Peter,

Ok, it looks like the PCB is designed for a 22RH544/00R (probably 22AH567 as well). Then the L/R switch, attenuator potmeter and rumble filter switch will fit without modification to the rear panel.
For the 544/50R and 532 some extra drilling is necessary. The 532 is in two versions: First one had a pushbutton for the input sensitivity, from PL01 onwards there was a 3-way switch, which can be re-used.

Regards, Rob.
Mijn PCB's zijn groen, dat is mijn bijdrage aan het milieu.
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