Hi ,

I am the happy owner of Beovox Penta speakers. The speakers are in bad shape and I want to restore them. The sound is fantastic( drived by a tube amplifier)  and compared with my BL8000 they sound in every way better.  

The speakers had all the drivers replaced by B&O(maybe) but how I could be sure that the new drivers are originals B&O?

The spare parts I need for the restore project are: the top end plate (left and right),  the base for 1 speaker,  the front covers    and     the  screws neded to fix the base !  Is there a possibility to order them at B&O? I wonder also whether or not the spare parts for Beovox Penta fit with the ones from Beolab3 Penta?

Any help will be highly appreciated!,

thanks everyone,

constantine

Most everything I order for Pentas is available from B&O spares stock but at a price! Cosmetic items are common thoughout the Penta range as are the drivers. The differences are in the display and amplifiers.

I doubt whether non B&O original drivers would fit in the holes/cutouts but I am prepared to be wrong on this.

When you ask about "original drivers" you have to remember that b&o probably didn't make any of those drivers.  They were likely 3rd party.  The mid range drivers and tweeter would probably be the easiest to replace as b&o cheaped out a little here and just used metal clamps on the back of the housing to hold the drivers against the hole openings, rather than actually screwing the driver mounting holes into the back face of the plastic housing.  The 5" woofers would be a little harder to replace as you'd have to find a driver with the same faceplate shape - that rounded off square like shape.  Some drivers do come with it though.  If the person who had the speakers before knew anything about speakers it's likely that the drivers he put in were actually better than the original b&o drivers.  As much as we like b&o you have to remember that they weren't putting top of the line drivers in those speakers.  High end drivers can cost over $100 each, and there's no way b&o was going to pack those pentas with $1000 worth of drivers.

If you do end up replacing any of the drivers you can't really go wrong with SEAS and Peerless.  They're two driver brands well known to audiophiles to make high quality drivers.  B&O actually used them in their older speakers when the profit margins weren't so steep, so you could argue that they would be more true to old b&o quality than those that came stock in the pentas.  Peter and Svend would still be proud I'm sure  :-)

How great would it be for an audiophile to see your speakers and say "yeah, they look nice but the b&o sound isn't that great for the price," and you can respond "yeah I agree, so I replaced the drivers with better ones."

 Anyway, your 5" woofers in the picture do look different from stock.  Can you take a closer picture of the driver?  Or more importantly unscrew one and see what the brand and model on the back is.

If you're interested, here's a good site for selling drivers:

http://www.madisound.com/catalog/index.php?cPath=45

This is zaph's site.  If you scroll down past his speaker projects you'll find he's done some great reviews and comparisons between different drivers:

www.zaphaudio.com

Good luck,

Austin
 

thanks Austin,

 

in fact the midrange drivers are Sammi?????) ( and the bass drivers are no name!!!) and it  does not fit completely  inside  because the drivers are biggers than the original ones( I cannot find any review !!!) .  It's bizarre that the sound is so good !

I am upset and in the same time happy, but what can I do?

regards

 

 

 

PS. it seems that the Sammy drivers are shielded!!!! The shielded part looks like the one in the picture . Any ideea if there is a possibility to remove the shielded part??????

Why do people do this????? The genuine drivers are £25 each or less which is cheap in my view.

11048437:

The speakers had all the drivers replaced by B&O(maybe) but how I could be sure that the new drivers are originals B&O?

Seeing your picture, at least the woofers are not originals.

camshaft:

If you do end up replacing any of the drivers you can't really go wrong with SEAS and Peerless.  They're two driver brands well known to audiophiles to make high quality drivers.  B&O actually used them in their older speakers when the profit margins weren't so steep, so you could argue that they would be more true to old b&o quality than those that came stock in the pentas.  Peter and Svend would still be proud I'm sure  :-)

Hello Austin,

One simple thing I would say is: no, don't do this ! I'm sure more recent drivers have a better sound than the original ones (technology has evolved), but this is not just about mounting speakers in an box. A loudspeaker is a coherent system: the filters, the enclosure, the different drivers types (tweeters, mediums, woofers) are made and chosen to work together. If you change anything, you will have a great risk of completely break the balance of you speaker, and get an awful sound. Just one exemple: the volume of the cabinet is very important and you must find a speaker that has the same frequency response and needs the same volume (liters) to accomplish the same frequency response inside the cabinet. In addition the driver must have the same sensibility. And finaly, the sound (I mean the character) of the driver must be very close to the original... very very difficult task !

A friend of mine replaced a woofer on his MS 150s, and the result was so awful that he just cannot use them anymore...

So my advice is definitely find original drivers.

Hey Emmanuel, you are definitely right about the design as a whole system.  I think many times though these designs are also used to make up for the shortcomings inherent in the speakers though.  In other words if a manufacturer is using a woofer that doesn't have a frequency response as good as they'd like in the lower range, they may slightly increase the volume of the cabinet or increase the length of the bass port to compensate.  Or if the tweeter they're using doesn't sound too great below 2.5khz they may move the midrange to tweeter crossover point up to 3kz and use a midrange that handles the higher frequencies well to make up for that issue with the tweeter.  My reasoning though was that if you pick a driver that you know performs better than the old driver across the entire frequency spectrum then you're likely to end up with a sound at least as good as the original.  Yes, the sound may be different but I'd be surprised if it actually sounded worse with a high quality driver.

Even though the Pentas were high quality speakers, they were still mass produced, and there would have been significant variation in the behavior of the drivers of different speakers.  These weren't $50,000 speakers where the individual driver of every speaker produced was tested and measured for frequency response, then matched with another tested speaker, and finally connected to a custom built cross-over circuit specifically made for those individual test results.  I love b&o design, but in the handful of b&o speakers I've dismantled I've seen them do things that audiophile speaker builders would cringe at.  I've never owned pentas though, so I can't necessarily say the same for them. 

This of course is all just my opinion based on what I already know, and am by no means a speaker expert or saying that you're wrong.  I believe your story about your friend with the ms150's, and if he did indeed replace the woofer with one of very high quality then it does make me question my own arguments.  At the same time, I didn't realize the penta drivers were still available, as mentioned by Joey.  If that's the case then I would probably just get the orginal b&o ones.  I was going under the assumption that they were no longer available and that the original poster was going to have to replace the drivers with aftermarket ones, which goes back to why I had just said to get high quality ones.

 Austin
 

Hi Austin,

My answer was essentially about "best pratices", and I understand your arguments. If you find a driver that is better on all the frequency range, it will surely outperform the original one on specific frequencies. But as the cabinet is designed for specific drivers (and to compensate their weaknesses if any) you will probably get highs and lows in the frequency response with a different new driver, no matter good it is. For example Pentas go to 40 Hz. The original woofers have surely not a linear response to 40 Hz. So the cabinet and filters are designed to help at this frequency. It you find a new speaker that you know performs better than the old driver across the entire frequency spectrum, you will get a louder (boosted) response at 40 Hz. So I still think replacing a driver is quite risky. Another important point is the sensivity of the driver. In addition, sensivity depends on the frequency, and of course this varies from one driver to another.

I agree with you on the fact that Pentas (and btw several other loudspeakers in the B&O range) are not high end speakers (their body seems simple plastic...). But the combination of an adapted cabinet/filter/drivers is more about acoustic calculations than expensive materials. You can find excellent loudspeakers at a ridiculous price simply because they are very coherent. About production of drivers, I think one unit is very very close to another. I think individual calibration is very rare, and only on very expensive speakers as you say.

I am not an expert too, and my responses are essentially based on principles, in a ideal world. I'm sure it is possible to get great results with new drivers, but choosing seems a hard task to me, that's I wanted to say.

Anyway, if original drivers are not available anymore (I do not have a recent update on their availability, so I can't tell), Constantine has no choice !

Best regards

Aren't Penta woofers 6 ohms impedance ? B&O have used that trick with other dual-woofer setups, Redline 140 springs to mind.

If so, they'll be practically impossible to replace with anything but originals.

Martin