Great idea Donnie! Come up with something like that, and you will be rich. But how bout calling it the ZWUTWATT?

Easy Piezon. I thought Donnie had a good idea. I just like to joke around.

I certainly never intend to offend anyone, but your remark was way out of line.

My post was a joke. Donnie is always joking around and I'm sure can take a joke. Since you thought it offensive I deleted it, with all the seriousness in this world I would hope we are still able to make a joke and it be recognized as such. Really no need for personal attacks. I still think a BS/snake oil detector would be a nice add-on or addition to an audio system for people pursuing this hobby.

I don't know what Showme wrote and I don't care but let's keep the hyper sensitive "offended" culture off of the Forum.

You'd think one could actually do this by have some device measure the output at the speaker terminals. Just like biamping or something, but instead you keep your amp plugged into your speaker terminals and this device also attaches to those terminals measuring the output. Would let somebody see instantly what their speakers are drawing currently, like some old school vumeters (why did those leave ).

Hi Donnie

I built a couple of boxes that would do what your describing about 4 years ago.  Its transformer coupled from the speaker terminals into the box with a hi z transformer with virtually no load so its a very light load on the speaker.  Then it goes through an attenuation circuit, a simple peak rectifier op amp circuit, and then into the ADC pin of a PICAXE micro controller.  The micro controller samples the ADC pin to get the peak voltage, converts to rms, and calculates power into the programmed speaker Z.  It can be set for 16, 8, 4, 2 and other load impedance's.  The power is then stored in a 256 deep memory so the last 256 samples are available.  Finally, the power is displayed, the last sample, along with the average power of all 256 entries in the memory, as well as the peak reading in memory.  It samples a few times a second and seems to be reasonably accurate.  I just happen to be testing an amp, so I hooked it up and tried a few things.  Got some pics when I was putting an 8.2v rms sine wave into an 8 ohm dummy load with the watt meter connected.  If I had let it run longer, memory would have filled with 8.6w readings so average and peak would all be 8.6w.  










I could let you borrow one if you want.  99.9w is the current limitation, 99.9w means 99.9w or higher.  


Dan

The physics of this thread are beyond me but I wonder if such a device is possible given how Steve's amps seem to perform beyond their specs.  A couple years ago Steve did some testing with his 40W ZMA and was getting 140W output.

What would be nice is to be able to read the loudspeakers actual impedance in real time and display it with the appropriate weighting.  Setting it to 16, 8, 4 ohm because that's what the speaker claims is nominal may not always tell the real story.  Since a speakers impedance swings from on average 30 to 6 to 30 ohms based on frequency, and in extreme cases 100 to 6 to 100 ohms, a true story must be calculated based on how much time it spends at each end.  Also, there is the voltage/current created by the voice coil moving backwards through the speaker cable into the outputs of the amplifier.  Different amplifiers deal with this differently.  Tube amps really don't care.  Solid state on the other hand really do care.  Sadly I'm not smart enough to design such a device, but I'd love to compare it's results.   I'll buy the first one : )

Steve

Steve, Donnie, Dank,

Donnie is correct about the top questions asked being, "How many watts do I need?" or "Is 2 watts enough?"

If one of you could come up with the battery driven device Steve mentioned, and it could be sold cheaply enough, That would be a fantastic tool for evaluating speakers, and thus watts needed (or desired ).

Something else that I've thought about too, is that with the "Is 2 watt's enough?" question being the main one, It'd be great to keep several Zen's in stock at all times, and advertise that it can be tried at home upon request, returned if not satisfied, or paid for if satisfied. I'll bet more would be sold like that. I'm not sure if that's doable or not. (the honor system is not as prevalent these days. Of course a persons home would have to be put up as collateral ) I guess shipping cost would be an obstacle too.

Another option would be the "Randy" method. Have folks with a Zen setup (or any Decware amp), volunteer their homes as a listening station for amp and speaker evaluation. I'd be up for that, although I may be a bit outside of a lot of folks reach in central Mississippi.

Post Covid, I'd offer my system to anyone who wanted to evaluate a 25th in the Chicago area Geno.

Another way might be for us to create a sticky with our amp, speaker brand/model and room size (maybe listening SPL).  We probably have all Decware speakers covered, Caintuck, Omega, Tekton, Zu.  Any other high sensitivity brands?

Or Steve of somebody create the little box.  You put down a deposit and it's sent to your home for a 1 week evaluation.  Refunded upon return.  You are only out shipping.

Yes, I appreciate the system listing.  I've contacted a member or two and I've had a few contacts as well.

I try to keep mine updated...

Hey everyone,

I also had this question when I was trying to pick a Decware amp. This may be simplistic (or miss the point), but aren’t we talking about a dB meter?  If we can assume that all the amplifiers will sound good then it’s just a matter of if it gets loud enough. I could have sworn that Steve put up a graphic on this website that was a chart showing watts vs speaker sensitivity and the correlating dB level. I also found this:

https://myhometheater.homestead.com/splcalculator.html

Whether I’m missing the boat or not, I will second the sentiment of a great group of very helpful people.