Flex Your PCD Mettle:

[NEO Dan]

Re: Flex Your PCD Mettle:

Is that good or bad?
...

I'm still working on other ideas and hoping to get the price lower.

Hi Erich,
I think it's very good, maybe too good. I bet Earl would agree with me on this one :D

[johnnyrichards]

Re: Flex Your PCD Mettle:

This thread accounts for ~33% of all posts on Tech Talk:eek:

[Pete Schumacher]

Re: Flex Your PCD Mettle:

Is that good or bad?

A few weeks ago the company gave a higher amount, but said they'd have to go over a few things on the rear mounting plate and hoped for a lower price.

I can get it done for a decent amount cheaper, but the price of the mold is 10's of thousands of dollars. If I thought the demand would justify 1000's of parts, I'd chance it. But I just don't know.

I'm still working on other ideas and hoping to get the price lower.

Once you have one, you have all you need for the next mold. It can't cost 10s of thousands to cast a negative of the waveguide, which could be used to make more of them. I mean, can't you just use expanding foam and a release agent to create a negative that could then be filled with epoxy resin?

[Erich H]

Re: Flex Your PCD Mettle:

SEOS 15" for ~$65? WOW!!!

Is that good or bad?

About a month or so ago the company gave a higher amount, but said they'd have to go over a few things on the rear mounting plate and hoped for a lower price.

I can get it done for a decent amount cheaper, but the price of the mold is 10's of thousands of dollars. If I thought the demand would justify 1000's of parts, I'd chance it. But I just don't know.

I'm still working on other ideas and hoping to get the price lower.

[NEO Dan]

Re: Flex Your PCD Mettle:

The other company should have some me quotes shortly. They gave me estimates of about $65 for fiberglass. Shipping would be very cheap due to their light weight. I won't mind packaging them up for free because it will only take a few minutes. Once the other company commits to an accurate price, I'll let you guys know.

Besides their extremely good performance, I'm glad these actually look really nice compared to some of the other waveguides out there.

SEOS 15" for ~$65? WOW!!!

[Erich H]

Re: Flex Your PCD Mettle:

On a seperate note...Those needing help sourcing replacement waveguides for the now unobtanium QSC's......check this link

http://www.avsforum.com/avs-vb/showt...291022&page=40

Scroll down for pics, measurements and how to get em. A forum member has graciously sourced em from oversees and measurments indicate they may be as good as it gets where WG's are concerned.:D

The other company should have some me quotes shortly. They gave me estimates of about $65 for fiberglass. Shipping would be very cheap due to their light weight. I won't mind packaging them up for free because it will only take a few minutes. Once the other company commits to an accurate price, I'll let you guys know.

Besides their extremely good performance, I'm glad these actually look really nice compared to some of the other waveguides out there.

[smokarz]

Re: Flex Your PCD Mettle:

If the mic can't "see" the driver exit, it won't hear it at those frequencies. Same for a listener, which is part of why exponential horns beam up high.

I had the Behringer cx3400 and it was silent, but it did have other issues. Had a similar BBE EQ(one of their high end models) and it hissed from one channel. The sales guy said he tried it in the shop, and no hiss. Not sure if he's full of it or not, but I think to some degree it's just luck with all this mass produced and untested or not thoroughly tested stuff. The consumer has become part of the quality control team and the savings are passed on to you.:eek:

Even though the Audyssey mic is tiny, I wouldn't trust it either(at all). Personally I can't see where REW would bring on any issues, but holm should work just fine as well. On axis, my d220 did go to 20kHz, but also fell rapidly off axis. In room and 10ft away, it was always down several dB. Probably a good thing. I would definitely try a calibrated mic first and a closer distance like 3 ft or less--that way you can be sure of your results.

Dan

thanks guys,

i will take close measuremement tonight at 1m and report back. i also have a diy mic based on the pansonic capsule that i can try.

i was hoping that this falls off at the listening position is a characteristic of the d220, and that nothing terrible went wrong with my build or my driver is defective.

[Mayhem13]

Re: Flex Your PCD Mettle:

On a seperate note...Those needing help sourcing replacement waveguides for the now unobtanium QSC's......check this link

http://www.avsforum.com/avs-vb/showt...291022&page=40

Scroll down for pics, measurements and how to get em. A forum member has graciously sourced em from oversees and measurments indicate they may be as good as it gets where WG's are concerned.:D

[dantheman]

Re: Flex Your PCD Mettle:

I had the Behringer cx3400 and it was silent, but it did have other issues. Had a similar BBE EQ(one of their high end models) and it hissed from one channel. The sales guy said he tried it in the shop, and no hiss. Not sure if he's full of it or not, but I think to some degree it's just luck with all this mass produced and untested or not thoroughly tested stuff. The consumer has become part of the quality control team and the savings are passed on to you.:eek:

Even though the Audyssey mic is tiny, I wouldn't trust it either(at all). Personally I can't see where REW would bring on any issues, but holm should work just fine as well. On axis, my d220 did go to 20kHz, but also fell rapidly off axis. In room and 10ft away, it was always down several dB. Probably a good thing. I would definitely try a calibrated mic first and a closer distance like 3 ft or less--that way you can be sure of your results.

Dan

[bwaslo]

Re: Flex Your PCD Mettle:

If the mic can't "see" the driver exit, it won't hear it at those frequencies. Same for a listener, which is part of why exponential horns beam up high.

[Pete Schumacher]

Re: d220 falling off at 10khz.........

sorry, i am fairly new with diy as this is my first speaker build.

1) how do i measure the driver "raw"?

2) i use REW software with the Audyssey mic that came with my Integra processor to take measurements. the measurement above was taken at the listening position, roughly 12ft away from speakers.

thanks!

I wouldn't trust the Audessey mic at that frequency either.

[fntn]

Re: Flex Your PCD Mettle:

Raw can be with or without a baffle but in either case - not connected to the crossover. This means you need to ensure that it's protected from applying voltages at low frequencies. The software you're using should allow for a high pass signal sweep from 1khz up. I use a free standing signal generator and spectrum analyzer on my work bench. For in room measurements, I use Holm Impulse - a free tool that works well with a laptop and USB card and has some really nice, simple impulse analysis features. If you're having trouble getting a high pass sweep out of your setup - I'm sure there are others here who are very familiar with what you're using. Whatever you do, be sure to adequately fuse (fast blow less than a few amps) your test rig to protect the tweeter from the application of excessive low frequency power.

[smokarz]

Re: d220 falling off at 10khz.........

Measure your driver "raw". Most likely, you need to double check your crossover. The raw measurement will confirm that for you - or it will show your driver is damaged/defective. Room modes are a low frequency issue. How are you measuring output?

sorry, i am fairly new with diy as this is my first speaker build.

1) how do i measure the driver "raw"?

2) i use REW software with the Audyssey mic that came with my Integra processor to take measurements. the measurement above was taken at the listening position, roughly 12ft away from speakers.

thanks!

[fntn]

Re: d220 falling off at 10khz.........

does any one have experience with the d220 falling off way early, around 10khz?


or is this due to my room modes?

thanks!

Measure your driver "raw". Most likely, you need to double check your crossover. The raw measurement will confirm that for you - or it will show your driver is damaged/defective. Room modes are a low frequency issue. How are you measuring output?

[smokarz]

d220 falling off at 10khz.........

does any one have experience with the d220 falling off way early, around 10khz?


or is this due to my room modes?


thanks!