10F/8424 & RS225-8 FAST / WAW Ref Monitor

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Possibly the finest "kitchen radio" I have ever heard? My basement repairs are still not done and my main system has been sitting there unused in storage upstairs for 2 months now. So I decided to dust it off and put it in my kitchen. Here are the 10F/RS225 FAST speakers with one of Hugh's new 35w Class A amps (cooled with 4 silent PWM fan cooled CPU heatsinks) and all fed by an Amazon Dot for source. Extremely easy to use and great sounding.

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Not bad for a kitchen system! Hugh's new 35 watt Class A amps? Please tell us more. Did I somehow miss this thread or are they a commercial product he's selling?

I have a Dot on my kitchen system as well. In all honesty my $15 bluetooth receiver sounded WAY better but I've gotten used to the sound of the Dot now. It's okay.

Good luck on getting the basement finished up, X!
 
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I can’t give technical specifics since it’s a commercial design, but the sound, as you might expect from Hugh, is superb. It does everything just right. The amp has a lots of caps right on board for the built in power supply. The distance from power supply to outputs is very short and as you might expect, the impedance is very low for deep impactful bass.
 
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I changed the Dot to a dedicated Sanwu Bluetooth streamer device followed by my OPA1688 dual parallel headphone amp as a preamp, and I have to admit, the sound is much better than the Dot by itself. Although most of it may just be the preamp. The volume of course, can be turned up past clipping now if desired and this amp holds up very well. Still playing super clean at loud levels. Very clear yet loud. I even put some hip hop on and the bass kick was very good.

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Ahem, I decided to develop a more efficient version of the ALPHA, which clips on negative half cycle at -17V, a long way off 24V.
The technique is unusual but works very well. With 28V volts, only 4V more than the ALPHA rails, gives it 35W into 8R and around 60W into 4R.
When X built and auditioned we decided to develop it further to a commercial product which will be sold for dollars.

Now I'm absorbed in the case issues, having spent two months poring over the pcb design, which includes SS relay protection for the speakers.

It will be announced in three months, for Xmas, as a new product. I hope, that is, if my metal spinners are happy to deliver.......

According to X, it might be Aspen's best amplifier yet, who knows? I am still waiting on the 350x150mm heatsinks, each channel dissipates 98W, so while a CPU cooler is a great idea, I believe a very large heatsink will be just sufficient.

I'm sorry, but I cannot give too many designs to the forum open source, I have to sell a few of the best for those who do not build their own....... they want their products, and I need to make my business earn its keep.

Hugh
 
Thank you Zia, much appreciated!

I am hoping that I will have this amp going in a couple of weeks. Then I will be able to know for myself that it's good. X insists it's good but I have to experience it myself!

As you may realise, I am only half-hearted in the audio business now, but my good sense tells me that I should never spend more money on development that I can recover in sales, it is a matter of pride!

Hugh
 
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I am listening to a cover of Billie Jean by The Civil Wars. Hugh’s new amplifier with my FAST speakers sounds simply great. The guitar dynamics has great realism with the transient perfect aspect and the amp really delivers. Perhaps one of the best amps I have heard.

YouTube

Oh, and I can’t beleive how loud it can get and simply shows no sign of strain - just effortless.
 
I've been on a mission of my own.... following yours! :)

I was trying to patch up together a setup that would follow yours, but with the parts I had available to me, and hopefully would have the transients of the Harsch XO I had been experimenting with miniDSP.

It's been a couple months....

This weekend, we are house-bound with that typhoon outside our doors, so, I figured I'd spend a full day on testing combinations.

Yesterday was a complete bust. Terrible setups, even working with XSim.. it didn't produce anything good, surely because of user error and bad choices on combinations of drivers and XOs.

Went to a little gathering of friends, played music (electric ukulele on my part) and it cheered me up after that horrible day with REW and a mic.

Woke up this morning and patched up a kit I had hopes for. It was a TB W8-1363sbf subwoofer in a sealed enclosure with a 4.8mH inductor, the Visaton B80 running free in a too small sealed enclosure that I had, and that was not bad. I decided to add a ribbon on top of that with a single 2.2uF cap and a resistor to pad it down to add some air and horizontal dispersion.

Ran REW, and was a bit surprised at what I got. So, I made a second setup to have stereo and played some music.

X, now I get it when you say a transient perfect setup sounds incredible. And all that running 1st order XOs... I couldn't believe it! And there's still room for improvement! I can't imagine it being better than this, but I see it would be possible to correct a few things and improve even more.

The transients... on snappy sounds, they are drilling in the middle of both my ears.

The imaging is simply scary! Pin point accuracy.

After that, I spent close to 4 hours listening to my music library. Mesmerized. Crazy amount of detail, enough low end reach, and the transients...

I guess this is not full range forum stuff anymore... but it started out that way. And the B80 does most of the coverage. :)

Here's the FR, impulse and group delay. Still room for improvements. I'll be working on that to see how far I can take this. But, I'll be listening some more, getting stoked for a while!

All this to basically say thank you, XRK971, for showing us your experiments and steering us into good designs, and a shout out to wesayso, whose perseverance is a motivator in itself!

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Just watched a TV show with the new setup, and it was involving.
Clean and clear vocals, immersing background music. It's going to be hard to take it apart and see what really makes it tick! I'll probably do that in a week.. or a month! I'm enjoying this way too much.

For example, I like to play Little Wings, by Stevie Ray Vaughn ... If I can hear his amplifier buzz, I know I have clarity. Same with Time, by Pink Floyd... hearing the synth modulations after the clocks ringing.

I looked up the W6-1139. To play with the B80 in sealed enclosures, you'll need a carefully designed XO, or better yet, an active setup like a miniDSP. The W6 starts dropping at 100Hz, according to TB's graph. The B80 sealed start dropping at 200Hz. So, they will need careful planning. The tweeters will be easier to deal with.

The Visaton are great. They shouldn't be waiting in a box! ;)

Get busy! :)
 
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Nice work Perceval! Glad you can hear what I have been talking about. And do you agree that before hearing it, you were not sure what you were missing and it’s basically “you don’t know what you don’t know”. But having heard it, you can’t go back to what was before. You know it’s great when it makes you re-listen your collection. Congrats!
:cheers: