Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Need help troubleshooting my Dampp Chaser system

Loren, that is a great example. Let me fill in the rest of the details so we are comparing apples to apples.

It is 20 degrees farhenheit outside and the furnace hasn't been turned on all day so it si 40 degrees F in the house.

I turn the furnace on for an hour and the house temperature reaches 55 degrees.

Then, I turn it off again and let the house get back down to 40 degrees.

Then, I do what you sggest and set the thermostat to 70 degreees and turn the furnace on for an hour...guess what the house is after an hour....55 degrees.

If you work at a level below the thermostat setting it won't be different.

You may not want a powerful humidifier inside the piano.

In your extraordinarily dry conditions, to get the kind of rapid response you seem to want, you would obviously need a more powerful humidifier.

But, is is really a good idea to have a humidifier that powerful so close to the strings and other metal parts?

Edit: Also, is it a good idea to have the humidifier running continuously next to the strings and other metal parts without cycling off? ? Even if the piano has not yet reached the "ideal" humidity?

One other thing just came to mind...

Even though D-C Corp. has explained to some extent the functioning of the humidistat, there may be proprietary aspects of its design that they simply cannot reveal without injuring themselves. If so, we may never be able to fully resolve all questions relating to it.

Tim, we've covered this before. The goal here is not to humidify the air; it's to maintain a certain EMC in the wood itself, to prevent condensation, and to create some airflow without any moving parts. Different problem; different solution.



Again, incorrect. Across all the wild theories of wood cell membrane moisture transfer, and all the other hypotheticals spun out of thin air, the rubber meets the road at the pitch of the piano. When it's too dry, the piano goes flat. End of story, and something measured by every technician when tuning.

--Cy--

Thank you! I think you may have finally interjected into this thread exactly what was needed, and something I never even considered, EMC. The humidity level of the air is not what is being addressed, the moisture content of the wood is; and that is something that takes time. I knew waiting at least three weeks before any measurable effect on the piano could be gauged was key.

Sorry to disappoint you Loren, but moisture content and air humidity are related. DC and other folks know that 42% is ideal RH...know why? because at 42% air humidity, wood eventually gets to 7 or 8% moisture content. (Check me on the 7 or 8%, but the point is that they are related)

So if I can't get the air to 42%, the wood moiture content won't get to 7 or 8%. Not in a day, a week, 3 weeks, or 3 years.

Equilibrium moisture content is where the wood is losing and gaining moisture at the same rate, whatever level that may be, which is the goal of the system. This may or may not equal the level of the surrounding air.

The true measurement is a stable piano.

I would contend that exactly the opposite is true.

Regardless of the pitch motions of that piano, if the DC is not maintaining the air relative humidity that it claims to, it is NOT working. Something might be working but it is not the DC.

It is quite possible to have the humidity maintained correctly and still have a piano's pitch unstable.

It is quite possible to NOT have humidity maintained correctly and still have a piano's pitch stable.

What is not possible is to have a DC NOT work, and take credit for stable pitch. Having the DC work is the first step in this process, and a step that apparently most technicians skip. And most piano owners, obviously.

And by the way, it would be dead simple (and no more expensive) to design that control system correctly. That would give you much more time in the correct humidity range, much slower swings, and some small energy savings.

You would be amazed at how many people do not believe this.

I frequently get a complaint of a cold area where I work, and the first request is always to raise the thermostat. (most of our thermostats are set by computer)

I try to explain that if the temperature isn't getting to setpoint, raising the setpoint won't help. Something is broken and I'll send a mechanic. But the reaction is almost always "well just try it." Even from people who should know better.

Unstable humidity = unstable piano pitch, Tim. Simple as that.

As I said...the moisture content percent of the wood is most definitely lower than the RH% of the air but they are directly related.

You can find lookup tables and calculators that can tell you what the EMC will be for a given type of wood in a specific relative humidity.

The ture measurement of whether or not a DC is maintaining a relative humidty of 42% is to measure what the DC is measuring when the humidistat turns t humidifier / dehumidifier on and off...relative humidity in the air.

Pitch stability is also directly related to the moisture content of the soundboard which is directly related to the moisture on content of the air. So, yes...no argument there (not a surprise) the pitch stability is what we are after.

Here's the rub...there are more variables that affect the pitch stability:
1. how much the piano is played and how hard
2. how old the strings are (new strings stretch more than old strings)
3. how loose the tuning pins are
4. There's probably more...you would know better than I

So my point is why not measure something that only has one thing influencing it vs. something that has several things influencing it. My problem is also that my pitch stability is lousy since I put my DC in...4 cents flat in 4 weeks. This is why I started testing the thing. (note that I haven't taken any pitch measurements since I have been experimenting.)

I'll give you another example to make my point clear. My uncle has a grand piano with no Dampp Chaser installed and his tuner is always impressed with how stable his instrument is. It is almost always within 2 or 3 cents. So I guess his Dampp Chaser must be working perfectly...oh wait...he doesn't have a dampp chaser.

Here's another example that I will will make up. If I buy a brand new piano with new strings and install a DC, do you think the pitch stability will still be perfect in 3,6, 12 months? I doubt it. So I guess I can conclude that the DC wasn't working. Nope...the strings were just new so they were stretching.

Hard playing will put improperly tuned/set strings/pins out if tune, but will not change the overall pitch of the piano. Loose pins will put individual notes out of tune, some more than others. But an expanding or contracting soundboard is what most influences pitch in a piano.

This is becoming a futile argument. Humidity affects pianos. Period! The more stable an environment, the more stable the piano. Period! This is not even debatable.


Ok, I feel better now.

Deleted with apologies.

No- that's not the case-- wood will absorb water from any direction; if this were not the case, you would find it very difficult to apply stains and such things and have them penetrate... So, not "mostly", no-- it is certainly easier at the end-grains.


This is an excellent example of what I face--- are you not saying by this that you wuold recommend a piano D-C system for just about anyone who opens their windows in for spring and summer air?-- as, merely opening your windows in the spring will shoot your ambient RH% from 23% to 60%...
This is why I want the verification from D-C!



Again-- great minds don't always make for great thinking (I already mentioned Steinway's teflon age). So endorsement does not necessarily mean intelligence.


By the way, to ridicule DCB is not your answer either. Besides, I believe I am your target for those words, not him.
I've been in the business 10 years-(grew up around this business)--- my dad was in it for 40+ before we lost him...
These concerns are not coming from off the cuff--- nor from an average customer who may not understand the ins and outs.

I've exhausted anything useful I can contribute to this thread, and am getting cranky and sarcastic, so at this point I'm done. Good luck with it all!

You don't have to... It's been done-- you can get the consumer report on such things. They don't just say/insinuate/claim it will last 40,000 mi.- they prove it.

D-C's customers should not have to feel the need to do what DCB is doing...
-------

Now-- (clears throte)--- if I may take up page 7 of this thread? I didn't get to post this yesterday or last night.



That's not my entire position on D-C...but yes, you could summarize it like that, I suppose.
---------------------
We did get that email today from D-C.
I read their report--- actually it was an article for The Guild Journal by Don Galt, of only 1 page.
It dealt with a piano ("a 45" Studio of good quality") that was kept at Wash. University for nearly 3 years in the studio of its music building- being meither played, nor tuned during that time... This was Puget Sound-- indoor avg. RH 30-60%.
The RH% was recorded weekly from June-March.
To make a short report shorter-- it showed what we all knew-- that a piano is subject to widely varying humidity levels throughout the year.
Humidity levels on the chart were at their highest Dec.23-28 and Feb.-March (again Washington State-- i.e. rainy winters)...
Interesting enough, this report spoke nothing about D-C, except for the bold red banner at the top---- "The Piano Being Tested Was Not Protected by the Piano Life Saver System"...
The Data (again this is for the year):
C-52 varied on the chart from 9 cents sharp to 1 cent flat.
C#-29 12 cents sharp to 6.5 cents flat.
C-28 7 cents sharp to 1.5 cents flat.
They look at the variance overall I guess…and they note of course the bass break and how it varied so much more there.
Again- no surprise.
Notice the overall variance? In its natural environment, ranging 30-60% RH---- 12 cents off from the origin was the largest swing in a year.

My own note to go with this- it appears that the piano was not tuned before the test was taken. I think we know that a freshly tuned piano would hold a bit better than a piano that has been left to itself for say, 2 years and then recorded for the final year?
I set pins when I tune- as I'm sure many of you set strings...
Why? To get the tuning to hold better!
If this wasn't done before the test- we can assume that the variance might not have been quite so great. But- as it was- one year- 12 cents was the largest swing one way? Sounds like what I am experiencing.
But- again---- this proves nothing. Only that a piano in Puget Sound will fluctuate in its pitch due to humidity... This was somehow to get us to assume that IF this piano was "protected by a Piano Life Saver System" it would have performed much better. Perhaps it would-- there was no record of such made.

NOW- I'm frustrated with ALL of this topic, as it appears it is full of nothing but man's/woman's empty vain speculation (my own included).
I've come away with what I came.
(((Perhaps this is why you too are tired of the debate, Loren)))
I still have a sense that there is a very strong push to sell an item that has no verification that it can live up to what is 'insinuated'. Insinuation is not a guarantee- so I guess Dampp-Chaser is safe in that. But claims need supporting evidence (not opinion).

I'm far from sold. I'm sure I'll be looked at as closed-minded again for this. But- I cannot imagine another business or corporation on the market getting away with selling an item under such statements as have been made---- AND not being called to put forward evidence. To bring up your tires scenario- Firestone was torn into for 'insufficient testing'-- they tested and had results, but overlooked something.

Now, "doubling the life of a piano" (if this is truly a claim they make) is a silly statement to make. I could stand here and tell DCB that his piano's life will be seriously and permanently damaged. Does that make it true? Of course not---- BUT, I can prove it with just as many such tests. If I shout it loud enough and long enough, it still won't make it Truth. If I get innumerable people to join my shouting, still not truth.
So---- my stance with Dampp-Chaser is still unchanged…
Get some testing done and I'll give you my support----- when I see that the system doesn't do what my logic tells me it would over a long period of time--- that's when I'll change my opinion. This system costs a lot of money.

I do give my customers the options---- but, Loren, I ALWAYS push them to get the room controlled rather than the piano.
We both agree to this I'm sure. Only, I understand that spring through summer it's going to be open window time...the piano will go a little out---- this will be taken care of with the next tuning. ( By the way, isn't a piano with the system still getting tuned yearly?- does the customer actually get told that they now don't have to get it tuned as much- and scheduled so?)

When controlling the room RH can't be done---- AND, when I 'know' the piano is going to be seriously damaged from what is taking place--- I discuss the D-C as a possibility…Otherwise I do what was done for many, many generations before D-C came along--- I work with nature and the piano.

We've got another email in to D-C trying to get more…I'll come back to this topic (create a new post for you all)- if and when something meaningful comes up…You guys do the same for me- but please no more opinions to me as evidence...
And one more time here- I do not question that you guys have pianos that you see performing good right now (I have pianos I've seen performing the same as before the system- ie. the system not working).
I have never questioned any of your posts about your experience.
This has always been about verifying facts.

Thanks for hearing me out.

Sounds like we are done. That's cool with me. I'd always rather be around passionate people with an opinion so I got something out of this conversation. I'm a very curious person and enjoy doing research and troubleshooting problems. I also like my piano to be fairly on pitch. This is why I want to make sure the humidty levels are right in my piano. (My piano playing sounds bad enough on a well-tuned piano)

I once bought some Michelin tires that were guaranteed to last 60,000 miles. they only lasted 50,000 miles based on Michelin's criteria so the company gave me a prorated amount of money towards my next set. I love Michelin tires and always buy them. The second set I bought lasted over 60,000 miles. I think they are a great company that makes a great product.

By the way, just to be clear once again. There is no debate and I have never said that humidity doesn't affect pitch. If I believed that, than why would I have ever purchased a DC? I go to bed at night feeling good about this because it is one thing we can all agree on.

Happy Holidays everyone.

Nice. 10 years? Is that all? You're telling some of us who have been in it for 3 decades + times longer than you have that we're wrong and disagreeing with us on our personal views and findings? Hmmmmm.

Here's my family history.

My grandfather started my business in 1926. My father took it over him and was in it for 55 years. He built it up to the point where he also tuned, serviced, installed and sold pipe organs and tuned and serviced pianos. Full time, of course. Dad had two brothers who were in it full time one working with him, one working for him.

I started tuning after school when I was 12. I'm 54. I've been in it counting all of that for 42 years, or, 36 years full time tuning on average 1,000 pianos + per year. There is a lot of experience in my family history with pianos and Dampp Chaser systems. However, not that this matters but, I am "trying" to slow down a bit.

I have a cousin, my dads brothers son, who has also been in it for 37 years full time. With all of our knowledge and experience with these systems, working for colleges and many various other organizations, if one technician (YOU) is not willing to "apparently" take the word of ANY other technicians in this business, something is mighty screwy with this picture in my opinion.

Other technicians views are usually, "appreciated in here." You're new in town. There are and have been lots and lots of various posts in here regarding Dampp Chasers or Damp Chasers as some people spell them and lots of various contributions over time. Do a search and read up on some of them and their opinions.

I'm new to this forum so I don't know as much as someone who's been here longer, but I think these conversations would be more effective and civil if people focused more on the debate and observations vs people's credibility.

It's human nature to become defenisve when someone questions your opinion but debate is healthy. (I'm guilty of being defensive as well.)

I would encourage anyone who disagrees with my opnions or my testing to do their own testing and see what happens. It is pretty easy to test these things. Then we could have a really cool conversation about the results.

I would think you guys would enjoy experimenting and questioning conventional wisdom. Don't you experiement with tuning methods, voicing methods, etc?

This field is part art and part science. The art part makes one technician amazing when another one is just great. The science part can be measured and tested. I thought this was a perfect thing to try and test...so I did and continue to do so.

By the way, I have been logical and detail focused for 36 years. I am 5th generation of a very logical and detail oriented family and have a sister, many aunts and uncles who also share this approach. I even won a science fair in the 5th grade. (Just trying to keep this light...we should all get along and not take ourselves so seriously...)

I have a nephew that can play "Dixie" with his armpit. Light enough for ya?