Forum Replies Created
-
AuthorPosts
-
Close, but no cigar.
lol!
I’ve also come across the money and Legos.
Your reference to the valve-based radios happily reminded me of the console TV we had when I was a kid. My dad used to hide money (presumably from my mom) inside the cabinet. It probably never occurred to him that he was raising a future engineer that took apart everything in the house, to see how it worked, when my parents were away. 😉
Glitch
Guy: If you like speaker schematics (and I suspect that you do 😉 ) check out this one…
The cool thing that this one does is puts the speakers into series when both sets are selected. Note: the L&R channel signals originate from the upper left of the diagram.
RossJP: Just curious…
What did you have before the BC9500? Were you happy with the sound level?
Did you add the Redlines in order to get more volume or did you want rear speakers (or both)?
Glitch
But wouldn’t Beolabs reduce the load on the BC9500 because they are providing their own amplification? (Connected to BC9500’s PL output before its main amp stage)
Absolutely. My mistake. I misread the statement and was thinking “Beovox” (i.e. physically smaller speakers wouldn’t change anything).
How would the relative loudness between the front and rear speakers be controlled with a either a Beolab speaker or Passive solution?
Of course, if one wants really wants “loud”, two pair of Beolab Pentas would do the trick ;-).
Glitch
So maybe I’ll keep the 5700s up front and get some smaller Beolabs for the rear.
You will likely have the same issues with “smaller Beolabs for the rear”. The root of the problem is that the low impedance configuration that you are trying to run is pushing the BC9500 past its design limit.
How loud are you trying to achieve? I would expect that the BC9500/BV5700 would get pretty loud (louder than most people would want to listen).
Of course, “loud” is a relative term. Consider buying an inexpensive decibel sound level meter. This will give you a better idea of how loud things are actually getting. I use mine as a way to protect my precious hearing.
Have you considered running a powered subwoofer? This would allow you to offload the the power hungry low frequencies from the BC9500.
Glitch
Does anyone know is this normal? Am I just expecting too much?
You are probably expecting too much. Based on a quick search, the BC9500 appears to be only rated at 8 ohms. This typically means that the manufacturer expects you to hookup either one or two pairs of 8 ohm speakers. Running two pairs of 8 ohm speakers is roughly equivalent to running one pair of 4 ohm speakers (assuming the internal connections are in parallel). With this in mind, you shouldn’t have any issues running just your BV5700’s (which are 4 ohm) or just your Redlines (which are 8 ohm?).
The problem is when you try to run both, the equivalent impedance is roughly 2.7 ohms. Usually, one can get away with this as long as you keep the volume low, but this configuration is (probably) not how the receiver was intended to be used.
Are you having any issues running only one pair of speakers at a time?
If you don’t have any issues with running the BV5700’s by themselves, then the BC9500 is likely working properly. If you still have issues while running one pair, then they may be something else that needs to be addressed.
I wouldn’t recommend mixing different impedance speakers on the same amp from a sound level perspective. You may have noticed that one pair of speakers plays louder than the other. Matching the speaker’s impedance (and efficiency) will usually result in a better overall listening experience.
Glitch
Compare the T/S parameters of a driver restored with foam to one restored with rubber (both played in to losen up the stiff new surrounds)
How close was the driver with the new foam to the original? All of the Penta midrange surrounds that I’ve dealt with were already too far gone to make meaningful measurements.
For anyone doing a surround replacement: Running T/S parameters, even if it is a crude DIY version, is helpful to verify your work. In this scenario, you are looking for any outliers (which can be caused by a variety of reasons). It is also helpful for sorting drivers if you are trying to make your speakers as balanced (left to right) as possible.
Glitch
I don’t think that there is a consensus. The purists will say foam, since it has the best chance at delivering the same as stock performance. The rest will say rubber, presumably because they think it will last longer(?).
I’m firmly in the foam camp. My assumption is that modern foam formulations won’t have the degradation issues that the original ones did. Regardless of longevity, I’d rather listen to (possibly) higher performance than always be wondering what I gave up with the heavier rubber surrounds. YMMV.
Glitch
Glitch wrote: Are you still thinking about offering anything based on the “universal link adapter”?
(snip) Don’t want to go that way.
Fair enough. It seems like the numbers were against the ULA concept. The subset of people that have the need for such a device, would want to pay a fair price for it, and have the skills and motivation to write the supporting code would be pretty small. However, a similar argument can be made for something like the Beolab 90, yet it exists ;-).
Glitch
Who is interested in such a thing?
I’m interested in the “MasterLink USB adapter” (MUA). I would like to hear more technical details about the hardware and (of course) the price.
I’ve been planning a major redesign of my audio system/network. I’m not sure exactly what it will be, but it will include a mixture of vintage B&O equipment, as well as equipment from other manufacturers (both new, old, and older). About the only thing that I have figured-out is that nobody seems to offer a suitable solution. As such, I expect to have to develop something custom.
Are you still thinking about offering anything based on the “universal link adapter”?
I think that that platform has a lot of potential. However, I’m concerned about the “care and feeding” of it from a software build standpoint.
I like the idea that the MUA could be used from a Raspberry Pi (or other Linux based PC?). Have you considered including a DataLink interface to the MUA?
Glitch
That is the part that scares me– finding a local person (1h South of Lisbon) who can put all the required connectors (if that is what is needed) and make it all work.
I’m a fan of the terminated wall plates like Tignum suggested. They are also available for various styles of coax (RCA, RG6, etc.), banana plugs, and many others. If you go the CATx route, you will find that terminating the cables is the easiest part of the project. The crimp (and punchdown) tools are cheap and easy to use.
You may have to create your own design diagram to get things rolling. As you may have noticed from other people’s posts, there is no standard way of making one. Any drawing method (software or by hand) will work. When creating a design diagram it would be helpful to include the model name, type number, and relevant software revisions for each piece of equipment. I would also add a diagram revision number from the start to make it easier to relate a particular configuration to the current conversation.
As you have undoubtedly already figured out, the technical knowledge of some of the members of this forum is on par with (or better than) the best of the dealers and installers. Their passion for the subject matter is unsurpassed. A good strategy is to make it as easy as possible for people to help you.
Consider setting up a “bench mockup” if your system starts getting complex. The general idea behind this is you can hook up all of the equipment (in London) and test the connectivity, functionality and interactions before committing to your final layout in your house (in Portugal). This would also give you something to play with while your house is being built ;-). Open utility shelves can be handy if you have a lot of equipment.
Glitch
I am afraid it may destroy stylus by arm returning whilst stylus is still down.
FYI, you can test the operation with the cartridge removed. Remove the cartridge, put on a record, add a small weight to the tone arm to simulate the weight of the cartridge (so the arm will fall when appropriate). Hit “start”. Once the arm drops into position at the lead-in groove, give it a slight nudge toward the center of the record. The arm should continue moving to the lead-out groove, lift and return. Testing without a cartridge is the prudent way of verifying proper operation. HTH.
Glitch
22 November 2023 at 13:48 in reply to: Beolab, Beovox Pentas – Ein Lautsprecher für die Ewigkeit #33988Das Platinenlayout für R3 lässt die Frage aufkommen, ob es innerhalb von B&O einen Streit über das Tuning gab. (hopefully this “Google translated” properly)
Glitch
i am building a new home with polished concrete floors and want to cable in the floor.
Have you considered a strategy where you install conduits? You then run whatever cable that you want inside the conduit. This would allow you to “future proof” your system as switching to a new technology would be as easy as pulling out the old cabling and installing the new.
I’ve not done this for concrete floors, but a few of my friends have done something similar where a conduit is run between the basement and the attic of a two story house.
Glitch
My Beomaster 8000 is VERY heavy and I live near Portland, Oregon. Is there a repair shop in the Pacific Northwest?
Your desire to use a competent, local repair shop certainly makes sense. In the event that you can’t find one, you may want to consider alternatives.
Have you considered shipping just the amp boards for repair? This would solve the shipping weight problem.
There are (of course) downsides to this suggestion:
- You would need to do some rudimentary debugging to isolate the problem to a particular board. I suspect that several people here would be willing to help with this step.
- The main amp boards are buried pretty deep within the BM8000. They are not the easiest boards to remove.
- There is a reasonably high chance that you will break at least one other thing within the receiver while removing/replacing the boards. IMHO, this is why many shops won’t touch B&O equipment. BTW, simply shipping could also cause new issues with the receiver.
- I don’t know if any repair shops will work this way. On one hand, it helps them avoid the issues in #3 above. On the other hand, they open themselves up to having a customer botch the reinstall and try to lay the blame on the repair shop.
Glitch
Philip,
IMHO, this is the coolest thing that has been posted here in quite a while! I’m undoubtedly biased since your project aligns with many of my interests and projects.
I have many questions about what you have done so far. I will be watching this thread closely to see the level of information detail that you are willing to share.
Would you elaborate on the connectivity to the non-B&O world? Which specific “use cases” are you currently supporting?
Glitch
p.s. I fully understand how challenging it can be to find the female/board side connectors. I’ve run into a similar situation where a seemingly common connector is unobtainable new. In my case, I ended up salvaging the necessary connectors from used equipment.
Did the previous owner give you any clues on the service history of the speakers?
Personally, I would just listen to them for a while and see if I liked them. You have plenty of time to make a decision. If you decide that you really like them and they will be a “forever speaker” for you, then invest the time and money in them.
Keep in mind that any time you open up vintage electronics it can be a can of worms. You can also negatively effect the value of an item if you are not careful (i.e. a scratch from the slip of a screwdriver or broken plastic clips). I would pay more for a untouched/unrestored piece of equipment than one with an amateurish repair. YMMV.
Glitch
Could the previous owner have already replaced the foam? Are there any signs of work being done to the speakers?
Glitch
I will order new drivers off eBay. My only concern is the part numbers don’t exactly match. The one’s on eBay are 8480232, and mine is 8480239
If you can’t find drivers with the exact same part number, try to at least get a replacement with the same impedance. They probably will not sound the exactly that same as stock, but something with the same impedance has a much better chance at sounding OK than something with a different impedance.
Glitch
Epic,
I suggest that you try to remove the old surrounds and glue before ordering replacement surrounds. You may end up fatally damaging the driver cones, depending on the glue used and your skill at removing the olds parts. This also opens up the possibility of ordering surrounds that will conceal any flaws left from the previous work.
I would also be very careful with using any solvents. They can have unintended consequences. When they work, they can work very well. When they don’t, it can be a real mess. Small test areas are the prudent way to proceed.
Glitch
Can anyone provide an explanation for how the “beam width control” actually controls the beam width on the Beolab8? I understand what the feature is supposed to be. I understand how this feature is supposed to work on B&O speakers with mechanical baffles. It is not clear to me how B&O would accomplish this with a seemingly standard 3-way configuration.
Glitch
-
AuthorPosts
