Vandersteen 5a battery biased crossovers


I've been using my 5As nearly every day for over 2 and a half years now and I feel they are the best move I ever made in audio. I researched them (and many other speakers)thoroughly before I made my purchase. I must say that everything incorporated in this design makes more sense to me than any other speaker I've encountered(Richard Hardesty's review covers this all very well for those not familiar) The one feature I still wonder about though is the battery biased crossover. How much does this help the sound? I believe that after about 5 years the battery needs to be changed on each crossover. Has anyone here had the 5A long enough that this had to be done? Did you do it yourself or does it require shipping to the factory?( I think the batteries are soldered in place to keep from rattling)Also, has anyone just let this go and not really noticed a difference?
sonofjim
I am not sure what caps are used but any high voltage signal path application for caps generally requires high quality caps.

Most speakers use high quality polypropylene caps for the crossover ($5 to $10) as do Vandersteens (I think) - these do not need reforming like electrolytic caps (although like any cap they drift with use with most drift occuring in the first 100 hours). So I am not sure what the battery actually does unless? As for peformance - within a few minutes the capacitors within your speakers should perform optimally so I am not sure the advantage there either. (The rubber surround on the speaker drivers will also ease up after a few minutes each time you power up too and thermal heating of the voice coil will change the way the speaker behaves too - do you have a "block heater" on the driver motor assembly as we Canadians have on our cars? It would be a sensible addition if one is worried about capacitor warm up)
Sono, I have not heard my Vandys with dead batteries, but I have heard Audioquest DBS cables with batteries dead and after a day or so they sound like the cables that "come in the box" .Richard does nothing without due consideration. It is the dielectric he wants to keep constant. The batteries are marked/dated for replacement. Not to insult, but anyone can perform changing them.
Dead batteries in the crossover/filters make a difference. The bass response sheds some "body" or shall I say become somewhat anemic.

In my case, I bought a pair of the Vandersteen 5A's used and immediately placed them in storage for almost 3 years. I recently installed them about 3 weeks ago for the first time and my local dealer mentioned the batteries possibly needed replacement by now. He sold the pair to the original buyer.

Anyways the speakers sounded great from the start so i did not mess with batteries. However, I was chasing down a troublesome grounding hum in my system when I swapped my power conditioners around including power cords. When I finally isolated the culprit, I noticed that my 5As, sounded like the "soul or body" was just not there. I kept checking the bottom to feel if the subs were working. Mind you the bass was still there but just lacked WEIGHT.

Well Lo and behold, I picked up a brand new pair of filters yesterday evening (because I thought the original filters were lost after all these years in storage and I had to order a new set from my dealer) I installed the filters with all settings in the off position in my haste and frankly it just did not feel right. Luckily I was listening to the 2ce's at my dealer that afternoon paired with a GRAAF OTL so I knew this 5A was just MIA.

So I opened the filter, adjusted for my amp and VOILA, the 5A delivered. That was an eye opener. The batteries barely had enough juice after all these years and eventually shut off the filters, hence the anemic sound

The batteries are your typical 9V batteries and did not look difficult to change. I will watch my dealer change the batteries in the filters next week before I put them up for sale here.
I have thought a bit more about it and since a battery typically has about 1.7 ohms of internal resistance and since it must be part of the circuit somehow then you may need to worry about it. A leaky or corroded battery or a change in the battery internal resistance over time might affect the sound. If you think about it - a chemical battery will likely change properties over time quite a bit more than a stable polypropylene capacitor - so it might be advisable to replace/check this regularly....
It makes sense to keep them operational. I just wanted to see if anyone has crossed this bridge before me. Is there anyone here that has actually changed them already and can confirm that it requires no special ability or precautions?
I did some digging around. JBL use this Vandersteen idea in their K2 speaker. As you are probably aware capacitors vary in quality and linearity. If you bias a polypropylene cap then the distortion products (due to non-linearity) will still be there but they will all be even harmonics (more benign to our ears). Also the circuit should be such that it won't matter about the battery aging (normally connected to a 1 K or more resistor). It does mean that the circuit requires two much larger (more expensive) capacitors in series of twice the value of what you would need if you used one capacitor. Since capacitor non-linearities tend to increase with size, a lot will depend on a the careful choice of components if it is to be an improvement over a single capacitor.

It also opens the door to using polarized capacitors in a crossover although I don't think Vandersteen does this (he uses polypropylene)

Anyway - interesting stuff - I hope this helps. I have found an AES paper on this subject if you are interested.
Ask Boobtube he had a pair of 5's that needed batteries, he pulled the units out and sent them to Vandersteen.
Ion Long life type.
There is a total of 8 9V batteries you must install
one 9V in each X 5 High pass
and also three 9v in each of the speakers Internal Modular Crossover.
Make sure you are are a class act with soldering pencil as its important the 9Vs be soldered in tightly.
Removing the Back plate removing the screws and pulling out the modular Xovers then either perform yourself, Mail them out to Vandersteen Audio or Call you local Vandy dealer.
Cheers Johnnyr
Thanks,
I knew this wouldn't be as simple as changing a flashlight battery. Luckily, it looks like the originals have a life of around 5-7 years so I'm jumping the gun on this more than I thought. For a while I guess I'll just continue to sit back and enjoy this fabulous speaker.
When you decide to replace your 5a's batteries, you may want to consider using the longer-life Lithium version. When I shipped my crossovers to Richard Vandersteen for battery replacement, I included 6 new RadioShack 9V "Ultralife" Lithium batteries (3 per crossover).
Helpful thread, thanks all. When I pulled the crossover boards out of my speakers I found that one battery had apparently shorted, and had blown its guts out the bottom. I'm the original owner and do not know when this happened, my guess is that it has been like this since the factory test floor. The batteries are series connected so the blown open battery would have removed all 3 from the circuit.
All 8 batteries have fairly heavy wire soldered on to them and generous amounts of solder, I strongly suspect that the heat required to solder does internal damage to many of the batteries at installation.
I normally am a Vandersteen fan, but this is just a really awful design.
Jeff,

I see you have your 5As listed for sale. Will you be switching to a different speaker? If so, do you mind me asking what that might be?
Actually, getting the crossovers out is not hard at all...send back the silver boxes that the amps plug into as well. I've done it, sent it back to Vandersteen and reinstalled all of it....result is better sound....easily heard
Mr JeffJones you said the batteries are a bad design.
Bias on a coupling cap improves transparency dramatically, ask anybody who has replaced dead ones with new ones.
The batteries don't usually do that unless they are beyond the date written in the owners manual.
This hurts nothing and is easily cleaned up.
I like using the new 10 year Duracell's
The connections need to be soldered because any noise because of the connection passes through the cap as an audio signal, so push on connectors would be a problem (think about the battery in your remote).
Best JohnnyR
I changed them myself when I had the 5's with the help of jeweler friend. He supplied me with some nice silver. I agree about the heat on the batteries but what else can he do. He seems to have "mastered" this design.
Audioconnection - I didn't say that the batteries are a 'bad' design. I said "really awful" :). Not disputing their function in providing bias voltage, I just think that they were probably added as an after thought/ improvement subsequent to testing and soldered only because there is not ample room to provide for connectors (we do circuit design & prototyping at my place of work and stuff like this happens, redoing boards is expensive, for premium priced components though I think it is time to bite the bullet and give the poor buyer a cheap, simple, and reliable means to swap batteries, the other thing is that sometimes when board layout is done you remember all components but forget things like connectors that are unique to one component).

Not sure what you mean about the battery in my remote, pressure connectors are typically found throughout every component of a stereo system, including several wire to lug points on the Vandy's, and they work just fine, which is a good thing because soldering to my TT cartridge would be a real nerve wracking job :). If I was going to be concerned about a pressure connection in the Vandy's (and I'm not) I'd worry about the tiny spring loaded contacts in the impedance matching dip switch arrays. The contacts on a 9v battery are huge - gigantic - enormous (pick your favorite word here :) ) in relation to their electrical requirements.

Sounds like I'm anti Vandy & I'm really not, the big things (sound quality, value etc) I'm happy with, just expected he would have cleaned up some detail level / attention to detail things better (the batteries, one speaker was missing the screws that hold crossover to speaker, both 110v subwoofer amp receptacles required bending so power cords would be securely connected, I think that is it, all easy enough to fix but I don't think the buyer should have to).

Sonofjim - not sure about which. Am thinking I want to take to whole system to something SET like though. Midrange lush, less truth but more beauty. May just keep the Vandy's and push them with an original issue BAT VK75 for a while. May go all the way to a flea amp and super high efficiency speakers.

Bjesien - If you swap them again, a lighter gauge wire will let you cut down on battery heating and still get a good connection. If you have the occasion to see a 9v battery with the innards on the outside you will see some very light gauge wire used in a series connection, it works.
Jeff Jones
Put connectors on if you like, there is room for them but remember any noise in the connection will be passed by the caps as noise.
In circuits like this where there is no current flow over a 7 year period of time (basically shelf life) the solder and wire is cheap insurance.

The M5-HP being run un soldered is very risky as 9 volts of noise into a typical amplifier will be one hell of a damaging pop!
As far as quality, I defy you to find another speaker with as much technology and raw parts count for twice the price.
Much of the technology found in the 5A can't be found in any speaker for any price.
By the way the new Model Seven has 36 volts of lithium SOLDERED onto the crossover board. Some how I don't think that was an oversight also.
Best
JohnnyR
Audioconnection - Actually I soldered lighter gauge wire (less chance of damage from overheating) as I could not find room to fit the connectors on the high pass filters and doing the + - arrangement at the speaker crossovers would have been a real nuisance.

Do not understand your risk comment, 9v battery connectors work great and they have been around for 20's of years and used in millions of circuits, I don't think you can find anything that is more well proven rock solid reliable. If you are saying that an open circuit will create a pop, well, I've already had an open circuit when a battery blew up in my 5a, apparently from overheating due to soldering (my best guess) and you mentioned in your previous note that you have seen this also (and it is easy to clean up :)). I have never seen a 9v battery blow up in any other application, if I was concerned about blowing up components my first move would be to stop grossly overheating the battery terminals with soldering irons.

Sorry to hear that Vandy is hanging on to the solder thing in newer designs. Not in the customers best interest in my opinion, but as a once in 7 year thing it is something I think folks will be ok with.

As far as quality, I think you are right and the Vandy's are high quality in general but I suspect that you would agree that missing screws and loose connections and an exploded battery are not what I should have expected to find on my 5a's. As I noted before, none of this was hard to fix, just kind of figured I shouldn't have to.
Jeff Jones, I have changed the batteries on dozens of 5 and 5a and have never found a blown battery on one that was within the date noted in the owners manual.

You never said if your batteries were within the recommended date.
Where they new speakers or demos?
I have sold hundreds of Vandersteen speakers and find
them to have the highest quality control standards.
Disparaging a great product should be done carefully
with honesty and should not be trivial.

About the high-pass, if the connection has any noise or a intermittent connection the caps will couple this voltage change into the input of the amplifier with potentially bad results. Again the solid reason for not offering 9V clip on types as you had suggested, hope this clarifies.

My garage opener uses a 9 volt battery and corrosion is a problem. Some speakers end up in very humid conditions or salt air. If it is too much trouble for you, put in the 9V lithium's which last 11 to 12 years. Best JohnnyR
Audioconnection - "Disparaging a great product should be done carefully with honesty and should not be trivial."
Seems like you are implying that either I'm not being truthful or else some of the problems I had should be considered trivial and not reported? Every manufacturer has to keep on top of quality control and usually the customer gets feedback more in the way of "thank you for the information and we are sorry you had problems with our product".
Batteries were due for a change in 01/13 and I swapped them 03/13 so I guess I was 2 months past the explosion date :).
Jeff, did you contact(Vandersteen Audio) about this information and get an unsatisfactory response via phone or FAQ? Best JohnnyR
Audioconnection - We could just quit and declare peace on the topic if you want to.
Have talked to R.V. in the past, he said he had a reputation as a grouch but I found him personable and straightforward. Have not bugged him about the minor quality control things noted here (screws missing and loose receptacle to plug connections) or the battery thing which really just came up.
My previous comment was in response only to your "Disparaging a great product should be done carefully with honesty and should not be trivial."