I am not questioning Die_Bogeners skills and knowledge at all.
As mentioned, I have actually adopted a few of his ideas, and I have sent several B&O owners, asking for repairs in Germany, to him over the years.
He may like the sound of Pentas fitted with MKP capacitors and recommend it to others.
I just don't.

Despite many people wanting it to be - or wishing that it was - Penta was never an audiophile speaker.
It wasn't intended to be and it won't be unless drastically redesigned, which in my opinion would be a shame.
Penta is in my opinion one of the most beautiful speakers ever built, and it's an excellent speaker in its
own right, with an absolutely pleasant and nice sound.
The engineers did their best with their knowledge, experience and not least the limitations of the design they were presented with, and
clearly they must have faced a couple of challenges in the process; Cabinet volume and width quickly springs to mind.
Usually the drivers are the most difficult parts as their T/S parameters often seem to call for cabinet volumes that just cannot
be granted, resonance points etc. but B&O had some drivers custom produced and ended up with what I think is a more than
acceptable result, considering the design.
I'm sure they would have liked to introduce a 10-inch woofer somewhere, - it just couldn't be done, so they settled for
a group of four 5-inch drivers (pairing identical woofers is something that many speaker designers warn against doing, but something
that B&O have managed to succeed in since the 1970s (4700/P45/RL60,140 etc.)

When you judge Penta speakers performance you must keep in mind to sit down in a normal listening position.
Not stand up in front of the speaker as many people tend to do and as the speakers design somehow asks of you.
Generally, speakers should be placed at ear height - your ear height when listening, that is - which
for most owners of f.e. wall-panel speakers comes out as surprisingly low and why speakers like f.e. Beovox S45-2 should be on
stands rather than placed directly on the floor.
Pentas midrange and tweeter section is at the right height for this, and its woofers are distributed
above and below accordingly.

I agree, that many of the older, discretely built, amplifiers sound excellent, and I would almost always prefer to listen to one
of them rather than anything modern. Just as the case is with speakers - as mentioned, it seems to be the sound trend of the time.
It can make a pleasant sound, well, but the Beomaster 6000/4-channel really doesn't qualify to be up there
with Beomaster 4400 and 8000 in my opinion. It's a great design but in effect it is really nothing more than two Beomaster 901s.

Several of the newer, and highly praised, B&O speakers use composite enclosures and cabinets.
I'm a bit curious as to how you would improve the Pentas midrange enclosure?
And what would be achieved?

Martin

Hey Stereomensch,
werde es mir merken ;)
Hatte Die_Bogener schon angeschrieben, aber warscheinlich auf eine alte Mailadresse, da ich gesehen hatte, dass er wohl hier im Forum nicht mehr wirklich aktiv ist.
Ich habe auch nochmal geschaut und meine, dass das die mit den Plastikkappen sind.
hier noch ein Foto:
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Und ja, du hast die alte Version! :)

Bezüglich Umbauvorschlag:

Schau mal hier:

https://archivedforum2.beoworld.org/forums/t/17557.aspx?PageIndex=2

Hermann (Hfinette) hat den Umbau gemacht, den kannst du auch sonst mal fragen.

Gruss Christian

Dank dir für den Link!
Ich glaube ich habe so ziemlich alles gelesen, was zu dem Thema geschrieben wurde.
Anfangs hatte ich das Problem, dass ich mich an dem falschen Diagramm orientiert habe und da so meine konkreten Problemchen hatte.
Ich bin auch ehrlich, ich bin kein Elektroingenieur, sondern eher ein Typ mit einem Lötkolben und Interesse.

Jetzt habe ich, wie gesagt, die ganzen alten Roedersteiner durch Jantzen MKPs ersetzt und höre den Unterschied.
Was Dillen sagt, kann ich (zumindestens bis jetzt) bestätigen. Durch den Umbau der MKPs habe ich einen Verlust des Warmen Sounds. Die Höhen sind prägnanter geworden und das wollte ich auch, aber der "Verlust" ist ganz klar in den Mitten und in Tiefen.
Ich überlege momentan wieder die alten (falls ich sie nicht beschädigt habe) in den Tiefenbereichen einzubauen, oder die Verbindungen, ich habe hier Silber verwendet, durch Kupfer zu tauschen. (Ist für mich eigentlich Schwachsinn, aber vllt. sind die Kabel auch einfach zu dünn).
oder ich mache weiter und baue á la Die-Bogener um (wozu ich auch tendiere).
Die Hochtöner werde ich erstmal nicht wechseln, es sei denn, ich finde zufällig ein Paar in der Bucht.
Hattest du die Pentas vor und nach dem Umbau gehört?
Was hast du alles geändert? Welcher Unterschied war dann?

Viele Grüße
Kaya

You really should compare MKPs to fresh electrolytics - not to old and worn out electrolytics.

Martin

@dillen

can you recommend which ones?

Dillen wrote:

I am not questioning Die_Bogeners skills and knowledge at all.
As mentioned, I have actually adopted a few of his ideas, and I have sent several B&O owners, asking for repairs in Germany, to him over the years.
He may like the sound of Pentas fitted with MKP capacitors and recommend it to others.
I just don't.

That is perfectly fine. It just seems sometimes that people tend to forget rather quickly. Many of the old threads and in particular the pictures are unfortunately no longer available. But Die_Bogener was one of the most active, creative, and knowledgable contributors. Admittedly very few members formerly kindly asking for his advice are putting the exact same ideas and contributions they used to appreciate so much earlier now down. That is a bit irritating to me as far as trustworthiness is concerned. I am not particularly addressing you, not the least in fact, but I have observed such a tendency in general. I, however, can still very well remember the times when Die_Bogener was more active on here and many were still reaching out for him, asking for his advice, and having nothing but praise for his ideas and contributions.

Dillen wrote:

Despite many people wanting it to be - or wishing that it was - Penta was never an audiophile speaker.
It wasn't intended to be and it won't be unless drastically redesigned, which in my opinion would be a shame.
Penta is in my opinion one of the most beautiful speakers ever built, and it's an excellent speaker in its
own right, with an absolutely pleasant and nice sound.
The engineers did their best with their knowledge, experience and not least the limitations of the design they were presented with, and
clearly they must have faced a couple of challenges in the process; Cabinet volume and width quickly springs to mind.
Usually the drivers are the most difficult parts as their T/S parameters often seem to call for cabinet volumes that just cannot
be granted, resonance points etc. but B&O had some drivers custom produced and ended up with what I think is a more than
acceptable result, considering the design.
I'm sure they would have liked to introduce a 10-inch woofer somewhere, - it just couldn't be done, so they settled for
a group of four 5-inch drivers (pairing identical woofers is something that many speaker designers warn against doing, but something
that B&O have managed to succeed in since the 1970s (4700/P45/RL60,140 etc.)

I totally agree, and we are probably in a minority on that, but Penta is an astonishingly beautiful speaker. I have thought multiple times about swapping to Beolab 1s or Beolab 9s, but just couldn't convince myself that overall this will really be an improvement. I find Pentas to be utterly beautiful, but know many that will totally oppose that point of view. As far as Pentas being audiophile of not, it all depends. I prefer my M75s, but Pentas are a damn nice sounding speaker for what they are. Still one of the best in B&O's portfolio of active speakers if you ask me. Their strengths particularly shine when playing loud.

Dillen wrote:

I agree, that many of the older, discretely built, amplifiers sound excellent, and I would almost always prefer to listen to one
of them rather than anything modern. Just as the case is with speakers - as mentioned, it seems to be the sound trend of the time.
It can make a pleasant sound, well, but the Beomaster 6000/4-channel really doesn't qualify to be up there
with Beomaster 4400 and 8000 in my opinion. It's a great design but in effect it is really nothing more than two Beomaster 901s.

Ok, this is the tricky part. First, I was talking built quality, not sound quality. And built quality of the 6000 Quad ranks definitely up there in my book. However, as far as sound quality is concerned, I don't agree. I have owned roughly 10 Quads and stated before on the forum what sometimes seems to be forgotten. First, there are different generations of the Quad that showed remarkable differences electronically. The last generation for example didn't reduce volume when switching to double stereo, whereas the first generation did. Second, some of my Quads sounded surprisingly different. For example, one played as lound on volume 5 as some others did on volume 10. And no, there were no electronic defects. The Quad was B&O's first 4-channel receiver apparently and they were still experimenting with the design. Therefore, many more or less significant differences exist between individual models. There was no serial production back then. Individual examples were not entirely standardized. To make a long story short, I figured that there are well sounding Quads that for me rank up there with the other receivers named. However, they are few. What is more, replacing capacitors didn't do much good to the sound on the Quad. But that is just my experience. Of the many examples I have owned, I still possess one that is totally restored but with the original capacitors still fitted wherever possible. Needless to say that it is the example that outperformed all the others I have had, no matter whether fully resored with capacitors replaced or not. It is one of the last made and presumably was hardly used by the previous owner. Whether this is generalizable, I do not know.

My friend who helps me with the restaurations of the Quad and has done many (>20) was pretty surprised by the statement that the Quad essentially is two 901s in one cabinet. This information is repeated over and over again on here, but he doesn't agree. What is more, he actually likes the 901 very much as far as built quality, electronic design, and performance is concerned. Therefore, even if the Quad essentially was two 901s combined, that is not necessarily a bad thing.

Dillen wrote:

Several of the newer, and highly praised, B&O speakers use composite enclosures and cabinets.
I'm a bit curious as to how you would improve the Pentas midrange enclosure?
And what would be achieved?

The design is functional. But so are the Beogram 7000 etc. designs. It is just cheaply made.

Greetings,

Kai

Moin,

Ich habe nun die Pentas länger laufen lassen und habe so ziemlich alles gehört, was ich gut kenne, sodass ich mir einen Eindruck machen kann (Wohlgemerkt immer alles Subjektiv).
Von "Eagles - Hell Freezes Over", über "Brian Bromberg" bis hin zu Nicolas Jaar etc. Meistens direkt von Platte oder via Flac vom Rechner. Ich könnte jetzt noch mehrere Alben aufzählen, das wäre aber am Thema vorbei.

Naja, was soll ich sagen...
Irgendwie verfliegt das vorherige Vermissen der "Wärme". Genau kann ich es aber auch nicht beschreiben. Entweder mussten sie sich einspielen und haben tiefen dazugewonnen, oder ich nehme sie mit der Zeit anders wahr.
Als ich die Pentas frisch stehen hatte, habe ich sie direkt mit den M70 verglichen und die waren viel präziser. Sie haben eine ganz andere "Auflösung vom Bühnenbild" gehabt, was ich dann als Potential gesehen habe, da sie wirklich nicht so gut geklungen haben.
Mittlerweile spielen sie allerdings ziemlich Ähnlich.
Der tausch der Kondensatoren war somit genau richtig. Ob es jetzt MKPs oder normale Bipolare Elkos sein sollten, war mir garnicht mal so wichtig. Es ging eher darum, den relativ dumpfe Klang zu beseitigen (Was wohl daran lag, dass die Kondensatoren tatsächlich Ihren Zenit überschritten hatten).

Durch viel Internetrecherche kam ich dann auf den Mod von Die_Bogener, wobei die Bilder leider fehlten. Interessiert hatte es mich dennoch, gerade weil so viele darüber berichtet haben.
Ob ich es noch umsetzte bleibt fraglich. Bin ganz froh darüber, sie revidiert zu haben, ohne dass etwas schief ging :)
Optimieren kann man da ja immer noch.

Irgendwann wird trotzdem der Moment kommen, wo ich mich frage, ob sie ohne die MKPs besser geklungen hätten. Das kann ich nicht ändern und liegt auch eher in -meiner- Natur. Ob ich sie dann wieder zurück baue oder so lasse, kann ich jetzt nicht beantworten.

Stereomensch bzw. Christophe hatte die Idee mit dem DSP, mit dem ich jetzt versuchen ein bisschen rum zu testen. Dazu werde ich mir den minidsp 2x4 ("hd" oder nicht "hd" werde ich später entscheiden) holen und und mir einen Adapter bauen, damit Powerlink trotzdem noch funktioniert, denn auf das Display möchte ich nun wirklich nicht mehr verzichten.

Ich danke euch allen, für die eure Hilfe und finde es schön, dass für die Pentas noch so viel Passion übrig ist.

Werde weiterhin berichten, wie es weitergeht und welche Erfahrung ich mit dem DSP mache.

Vielen Dank / Thank You!

Kaya


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Hallo,

also ich habe folgende Sachen gemacht:

1. Gummi-Sicken für die Mitteltöner

2. Weichen und Verstärker von einem Techniker überprüfen lassen.

Fehlende Höhen habe ich nicht, aber ich habe auch die letzte Version mit dem anderen Hochtöner.

Mich stört eher, dass die Pentas nicht so tief gehen wie die Redline 7000 Lautsprecher.

Und die sind auch nicht so tief!

Gruss C