BillFitzmaurice.info

Also, if it seems too good to be true, then it probably is.

That's a tolerable output for a low power Wedgehorn application or a good driver in bridge mode to run a THT.

For under $400 might be worth a listen. I think I'll order one in just to put it through some paces.

tcorder wrote:Update time.

I measured the voltage on the inuke and is was a disappointing 27 to 28 volts which by my reconing makes it less than 200w channel and the fan started to run seriously fast. I feel I've been done. Oh well, should have expected it really.

As a matter of interest, I just did the same thing on my Yamaha P3500S. This is quoted at 450W Output power(20Hz-20kHz) at 4 ohms. I measured just under 20V.

tcorder wrote:pink noise in, volt meter on the output. When the limit lights came on read the voltage.

I see two problems with this approach:

1. Most regular DVM:s won't measure pink noise very well. They're usually designed for 50-60Hz sine wave.
2. That's not how amp manufacturers usually spec their products. Most common is a 1000Hz tone. The cheaters run a short pulse and ignore any power supply sagging. The honest run a continuous tone. Having both measurements is more valuable, but steady is most important.

Since it's about running amps for subwoofers measuring lower frequencies should be more important, and going below the mains frequency (50/60Hz) would possibly tell a little bit more about the power supply capacity.

RichardH wrote: This is quoted at 450W Output power(20Hz-20kHz) at 4 ohms. I measured just under 20V.

According to Yamaha the 3500 consumes 450w, total, at full output into 4 ohms. Running with 100% efficiency that makes its actual continuous long term capacity 225w/ch, so your 20v figure looks to be spot on.
If you dig deeper into the specs they say 1/8 power into 4 ohms is 148w, and that '1/8 power is typical of program material with occasional clipping. Refer to these figures for most applications.'
They also state that 1/3 power is 393w, and warn that ' 1/3 power represents program material with extremely heavy clipping.'

In other words the rated power figures are just so much piffel.

So then is the best way to choose a power amp to go to Guitar Center with a tone generator and a DMM? I think the dorks working there would give you strange looks.

ncgrove wrote:So then is the best way to choose a power amp to go to Guitar Center with a tone generator and a DMM? I think the dorks working there would give you strange looks.

Who cares if they do. Perhaps you will find one or two interested in the truth.

ncgrove wrote:So then is the best way to choose a power amp to go to Guitar Center with a tone generator and a DMM? I think the dorks working there would give you strange looks.

That's half the story. If you simply measure voltage just before the clip light, you'll find out a rough idea of what the amp can put out, but some amps sound really nasty at that point, and some are decent. My IPR amps can be full-on into the DDT limiters (effectively just below clip) and you can't tell at all. My Crown XLS402 sounds awful if the clip lights barely flash... they're both reputable amps in the same price range at close to the same output... the Crown will measure slightly more than the IPR, but you can't use it, so it doesn't matter much. It apparently has higher THD at the clip point.

So, measure voltage, but also read about others experience with the amp, and LISTEN to it at high volume (if you're going to run it that way). Trust your ears... if it sounds good... it is good. If you can't trust your ears... well... that's kind of like being a colorblind lighting director...

While trying the inuke out with bass, one channel only as I only had one cab 4 ohm, when the clip light came on there was no noticeable change in sound.

tcorder wrote:While trying the inuke out with bass, one channel only as I only had one cab 4 ohm, when the clip light came on there was no noticeable change in sound.

That may indicate a conservative clip indicator, which is wise, as not all users are judicious enough to keep it as it should be, only sporadically flashing.

When I tested my old amp, as in really old, made when mosfet was still a selling point, the clip indicator glowed up very gradually just as it hit 35V, right on for 300W @ 4 ohm. Right on 1.4V sinewave input at 0dB input attenuation. I guess they just used to trust operators back then.

A quick update on my inuke 3000. I used it for the first time 'live' last night driving the horns in my Otop 12s. It worked perfectly, ran all night without getting hot and the amp rack was considerably lighter so apart from the output power, it's not a bad amp at all so far.

tcorder wrote:A quick update on my inuke 3000. I used it for the first time 'live' last night driving the horns in my Otop 12s. It worked perfectly, ran all night without getting hot and the amp rack was considerably lighter so apart from the output power, it's not a bad amp at all so far.

If all it's driving is HF horns I doubt it's pushing more than 25 watts per cab. It may not be a bad amp at all, it's just unfortunate that it's so badly misrepresented.

It's still working.