[Evan]

Glitch wrote:

Evan wrote:

et me know what you guys think.

From a general sound perspective, I don’t see any reason why it wouldn’t work. As long as you keep the cabinet volume and reflex tube length/diameter the same you will, in general, have a similar frequency response. Even if you mess up the very low frequency response, this won’t be critical for voices since they don’t contain those frequencies. Would you actually be happy with the form factor? I’m having a hard time imagining what this would look like under a TV. Did you plan to have the bottom-most mid-range close to the floor? Not having the tweeter and mids at ear level may mess with the vertical dispersion. I don’t know if this is a better or worse trade-off versus having the mid-range array horizontal. Have you considered using a (well matched) pair of Pentas (in the original configuration) placed tight to sides of the TV? The mono pair would provide the a solid centered image and the apparent sweet spot could be roughly controlled by the angle. The other “surround” speakers could also be Pentas for the full overkill effect. ? Glitch

Yeah, seems like it, right? I know it will be impossible to match the cabinet coloration but hopefully in normal listening that isn’t such a huge issue.

I’m going to take some impedance measurements of each subsystem (woofer and mid) to find the critical tuning for the cabinet volumes etc. and use that as reference in the build later on.

As for form factor that is still TBD. It should be able to fit inside an Ikea Kallax unit (height-wise). We use a 2×4 kallax shelf for the under-tv area in the bedroom and I have removed one vertical piece to open up the middle area a bit. I’ll add a picture soon to make this all a little easier to explain. The living room setup is a little more difficult and I might have to put it on a stand in front of the TV unit as it is far less accommodating. Let’s be honest, this isn’t a project for the space-conscious!

I really want to print it so that it has the aesthetic of the original Penta geometry. But if it gets made from wood it will likely sound far far superior than a plastic cabinet.

The problem with putting the same signal through both speakers is that you only serve a listener exactly in-between them. My goal is to build the center channel so that it serves all listeners, even those sat to sides etc.

My vision is that this becomes repeatable. I want to be able to share this with those who may be interested enough so that they can build their own.

[Evan]

Die_Bogener wrote:

A Penta is way to big… a simple Redline 40/60/120 will do the job. The important thing is: the speaker must fit to human voice. Too much bass will destroy the effect… and a standard Penta will not work, you must first remove the bubble wrap foil in it’s sound way.

I hear you. Many speakers fit the role but the objective here is to match as closely as possible the sound of the left and right speakers.

[Evan]

Ravsted wrote:

I got a BeoLab 7.1 (wired using both left and right channel as center channel). It is at great center speaker with lot of power and clarity. If you go for at home-brew solution with a passive speaker I would build something around a non-B&O center speaker … A good second hand B&W or whatever you prefer. I believe that will give you a way better acoustic result. You can still modify the speaker cabinet to match the Pentas in some way.

I’m quite satisfied by the performance of the Penta, its an amazingly capable speaker to my ears. The mission here is to take the capability and repackage to suit the placement more efficiently, technically correct and maybe even elegantly.

I’m chasing down the exact same speakers because I want to keep the timbre between channels as close to each other as possible. Going outside B&O would miss the objective.

[Evan]

Thanks for the replies everyone! Nice to do some brainstorming among the like-minded. This is still a thought experiment for now (many other projects still in flight, as usual). I don’t like to keep crazy ideas to myself just in case there is someone else out there who wants to join in on the fun and build this stuff along with me.

Just for context, I have a BL10. Yes, it should do the job and sometimes did deliver the power it contained (mostly in gaming situations) but the overall sound character (timbre) was very very mismatched. Basically ended up not using it most of the time. Vocals are always the focus of the center channel but there is often times far more content coming through than just voice. Also this isn’t the only experience driving this project, many systems I have heard are usually weakest in the center channel for various reasons, but usually packaging related.

[Evan]

Happy to help print the parts if you decide to do so, just PM me. Although I can’t verify the fitment as I don’t have a pair of those speakers on hand.

[Evan]

Latest addiction: new-to-me pair of M100-2’s. Have been trying to get my hands on a pair of these for years now.

Swapped them into my humble corner of the office we refer to as the “clubhouse” before they make their journey home. They are effortlessly filling our warehouse with sound. Maybe I will swap them into the listening room if I find the time. They should annoy my colleagues downstairs with ease!

[Evan]

This is sad news indeed! I am very late to this thread but I would be remiss not to acknowledge Peter’s dedication and passion for B&O – both the products and community.

From my earliest years of BeoWorld forum reading/lurking/posting I remember seeing his constant updates and refinements to his system where he built a stand-alone ICEpower amp for his Pentas. As many have said in the posts above, his drawings and diagrams are legendary.

[Evan]

TheFinisher wrote:

they do sound very good , I mean end game speakers.

You’re making me want a pair of M100s even more. Why do you tease us!!

[Evan]

Glad you enjoyed it and found it useful.

I measured a few of them but not all. The ones I had measured were very close to spec. Unfortunately I think I tossed them so I can’t go back and check – sorry!

[Evan]

Glitch wrote:

I just finished a refresh of this Beomaster 4000. This receiver was a good example of why one shouldn’t just grab a spray can of “contact cleaner/lubricant” and spray indeterminately to fix a noisy potentiometer or switch. Whatever product the previous owner used seeped everywhere inside the receiver then turned into a hard waxy substance. Fortunately, I was able to fully disassemble the receiver and clean the “gunk” out of the chassis, sliders and switches. My plan for the receiver is to pair it with four Braun speakers from the same era. Braun speakers are actually somewhat rare in the US. I like to assemble systems with a theme. This will be my “70’s Euro-system”. I’m guessing that most of the forum members would just call it a “70’s system” I’m looking forward to experiencing the Ambiophonic feature. Does anyone have suggestions for era-appropriate recordings that highlight this feature? Glitch

Nice work. Really clean 4k you have there! I can’t wait to work through my BM4k. I have a BG4002 with CD4 built in and can’t wait to get the duo playing together one day.

[Evan]

jesnystrup@gmail.com wrote:

pepps wrote:

Evan wrote:

I’m back in the US for a little while so I’m trying to sort out one of my other previous acquisitions, BL Penta MK2. They need the full overhaul so I bought all 3 cap kits and new foam surrounds. These will be the main L/R channels in the master bedroom and the basis of a surround system (eventually!).

Looking forward to seeing/reading some more on this project.

Thats ALOT of work ..Let us know how it went Jess

Hey Jess – it definitely was a lot of work and still is! The project lives on when I have time for it.

You can find the full write up here: Evan’s MK2 BeoLab Pentas

[Evan]

Great thread, have been wanting to bring up a similar topic as I have contemplated something very similar.

Inspired by a configuration for architectural speakers by Meridian, I wonder if new life could be breathed into BL6000 and BeoLab 8000 speakers by building trios for wall mounting where space might be an issue for some. Meridian offers customers the ability to “array” their in-wall speakers so their customers with very large spaces / longer than usual listening distances (or need much higher SPL in their room). In their demo theater, Meridian uses three sets of three DSP-750 speakers as the L/C/R behind the projection screen. However they are mounted vertically unlike the icon depicts.

 

[Evan]

Hey Bihu – Powerlink signals are single ended, not able to send balanced signals that an XLR connector would usually carry. Of course you can use XLR if you want you will just have to make do with the positive and ground wired only.

Each Powerlink jack/cable/plug will carry both left and right channels.

For more details on the connector, see the Powerlink diagram here.

For a quick solution, visit Steve’s site linked at the bottom of this forum.

[Evan]

Beozip wrote:

But less is more …. so is B&O thinking and had create his own horizontally tablestand. This is very flexible. Do you know this stand?

 

Yes, I knew this stand was out there. I don’t really like the look of the bent wire and didn’t feel like hunting it down.

I enjoy designing things and I’m addicted to 3D printing so it was easy for me to do. Its good to flex the creative muscles every now and then.

Edit: Just checked the analytics and a whopping 7 people have downloaded it so far. Modest take rate but I’m glad a few people out there liked it enough to download 🙂

[Evan]

OldJack wrote:

LG77 G2 and Theatre

Brilliant looking room, Jack!

[Evan]

Ha! That’s a great idea! After writing my last post I realized I could build them as a tower of amps on a single plinth so that they form a “stereo” amplifier haha!

The system I am building is turning out to be very unique thanks to all these odd ingredients (which is something I’m beginning to appreciate!). It seems to be made of chess pieces! Almost nothing matches except for the Penta content.

I think for now I am going to stick with the BeoLab 200 plan once I sort out at least two, fully functional and refreshed amps.

[Evan]

Small update for you folks. Yesterday I drove 250 miles round trip to pick up these bad boys:

This is a pair of MK2 BeoLab Penta amplifiers and I managed to also find them on FB Marketplace.

One of them is working fine but the other is blowing fuses apparently. In a little while I will go through and recap these just as I did the original pair. I’ll swap one of these (or whichever one is working) into the bad speaker and repair the original amp fully at a later date.

The cool thing about this project is once both of the naughty amplifiers are back in shape I will have a pair of spare amps to put to work! I think I will be 3D printing some accessory parts to make them look like BeoLab 200s.

[Evan]

Leosgonewild wrote:

I have been dreaming of this for 10 years…

Congrats, Leo! Please add your listening impressions of the BeoLabs after some listening time! The all-black BV7 looks awesome, too.

I’d be very interested to hear how/if you recommend the BL7-4. I’m running a BeoLab 10 as my center channel and I never thought I would need more from a center channel until I put it in-between a pair of Beolab 5s. The BeoLab 10 is of seriously outgunned on SPL and low end (not the BL10’s fault) but the timbre of the 10 and 5 are extremely different. I wish I could fit a third 5 underneath my BV. The Beolab 10 seems to be very midrange-forward compared to the 5s (much sharper in the HF). I wonder if people reading this have the same opinion? MY Beolab 10 sounds so “warm” in the middle by comparison that I wonder if the tweeter is operating correctly.

[Evan]

Tignum wrote:

Today I finally replaced some unused coax wires with Cat7 cables and re-added my BeoMaster 6500 / BeoGram CD 7000 combo to my set-up. They are in the attic (study) and connected through a 1611 to go from MCL to ML, and a BLC to go from ML to NL. I made a little overview of the whole network :-). Next trial will be to connect the BL4000s directly to the Core. Until now I kept them in the larger ML network to avoid sync issues, but if they sound better without the Active and BLC in the chain, I will see to fix any delay issues and get an IR eye connected to the Core for Beo4 control in the kitchen. Regards, Johan

This is a true “system”! Nice work integrating everything and that “little overview” is actually an epic graphic!

That BV10 looks great by the way. I always miss mine.

[Evan]

Hey Lee –

First of all, good to see you are still poking around! I am very appreciative for your efforts in running BeoWorld. This platform helped me discover and develop a subject I have become quite passionate about – it has literally changed my life. For that I will always be grateful. As well there’s no doubt that Keith is an absolute legend and powerhouse making it all work.

The diehard enthusiasts will always be here, you can count on us. In my experience, the BeoCommunity used to be very centralized around BeoWorld in its 2007-2012 iteration (maybe a few more years after that). The seemingly endless number of FB groups/pages seem to have been the main undoing of the traffic we used to see at BW. BeoWorld will always be the place I go to share, though.

I think a price increase is overdue for Gold members but I can see how that might drive membership down even further. Chicken and egg indeed.

I also see the identity of the Prize Draw (and sir BottsWorth himself) are part of the BeoWorld brand, to lose it would be like losing part of BeoWorld. How many forums do you know do this?? Truly unique. However, I understand that we can’t live in fantasy land anymore. I agree with MM on maybe working the sponsorship angle more or attempting to find a way to subsidize somehow so you aren’t footing the bill yourself.

Evan

 

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