Small stereo active FRFR cab at last...

[Hhuent]

As @Rex
By using a non-flat, limited high extension speakers like the Spark, you're effectively putting another low pass filter on top of your output from the Axe-Fx. Again, not going to translate well to FOH, they'll get a much harsher signal.

Which, if that's what you want, then OK. I guess it doesn't matter if you're using it as backline, and not sending anything to FOH. But if you do send to FOH, you're always going to need another flat monitor source to double-check.

Sorry, Ican‘t follow you: the Spark has „nonflat limited high extension speakers“? The specs say 2x 10-inch speaker + 2x neodymium tweeter. They took this monitor for a testdrive against the usual suspects like RCF, Friedman, Yamaha and 5 others in a musicians magazine and it came out best. But maybe I got you wrong and I‘m barking up the wrong tree.
I can’t speak for the Spark but the test chart of my driver goes up to 17 kHz and the maker offered to check the cab to make sure. Sticking at trifles right now, the cab sounds terrific with my electric guitar and quite good with my acoustic and it renders the character of the IRs better than any cab I had before. I will keep you posted after the cab got inspected.

 

[yeky83]

Sorry, Ican‘t follow you: the Spark has „nonflat limited high extension speakers“? The specs say 2x 10-inch speaker + 2x neodymium tweeter. They took this monitor for a testdrive against the usual suspects like RCF, Friedman, Yamaha and 5 others in a musicians magazine and it came out best. But maybe I got you wrong and I‘m barking up the wrong tree.
I can’t speak for the Spark but the test chart of my driver goes up to 17 kHz and the maker offered to check the cab to make sure. Sticking at trifles right now, the cab sounds terrific with my electric guitar and quite good with my acoustic and it renders the character of the IRs better than any cab I had before. I will keep you posted after the cab got inspected.

Look at @merlin17's post, the Spark (his at least) isn't flat, and rolls off quite a lot past ~5 Khz, despite the Blueamps website rating of "80-25.000 Hz (-6 dB)":

View attachment 43728
Here‘s one of the measurements....

@Hhuent You've got a test chart of your custom made one? Cool, care to share?

 

[merlin17]

You've got a test chart of your custom made one? Cool, care to share?

No, that's my measurement.

I read the testdrives. The Spark came out as the only one not sounding harsh at higher frequencies. AFAIK they didn't measure its response. My measurement shows WHY it isn't on the harsh (or thruthful) side. I'd love to see a more professionally made measurement by BlueAmps (and not just a written specsheet). BUT (as I've said) it sounds good (at least with E-Gtr.), and so far my FOH people have not complained.

 

[yeky83]

No, that's my measurement.

I read the testdrives. The Spark came out as the only one not sounding harsh at higher frequencies. AFAIK they didn't measure its response. My measurement shows WHY it isn't on the harsh (or thruthful) side. I'd love to see a more professionally made measurement by BlueAmps (and not just a written specsheet). BUT (as I've said) it sounds good (at least with E-Gtr.), and so far my FOH people have not complained.

Meant to direct that question to Hhuent, edited my previous post to show it.

 

[Hhuent]

@Hhuent You've got a test chart of your custom made one? Cool, care to share? [/QUOTE]

Sorry, deleted the Mail of the builder already. It was only the chart of the driver and I remember a slight dip between 4 or 5 and 9 kHz and the roll off after 17 kHz. Don‘t know about the method. However, the sound is smooth, has that certain guitar cab feeling including higher frequencies, acoustic guitar sounds fine minus the “zing“ of the very top frequencies. If a totally flat curve would introduce harshness I would not want it. My Fender presets with Austinbuddys IRs, reverb and delay in stereo, coming from such a small box, make me more than happy. It better should considering the dough I spent. Let’s see what happens in a bigger room when I crank it up to drummer levels and Fletcher-Munson kicks in. Will post a follow-up.

 

[yeky83]

It was only the chart of the driver and I remember a slight dip between 4 or 5 and 9 kHz and the roll off after 17 kHz.

Chart of the driver? It would have to be a chart of the combined woofer & tweeter drivers in the cab, since that's the only way to get a full-frequency chart, no?

If a totally flat curve would introduce harshness I would not want it.

Totally flat speaker will not introduce harshness if your output from the Axe-Fx doesn't have harshness.
So harshness is better fixed from the Axe-Fx rather than by a non-flat speaker IMO, but whatever works!

My Fender presets with Austinbuddys IRs, reverb and delay in stereo, coming from such a small box, make me more than happy. Let’s see what happens in a bigger room when I crank it up to drummer levels. Will post a follow-up.

Thanks for sharing about the custom speaker, looking forward to the follow-up!