Starkrimson® Ultra Amplifier Modules -- 250/500W into 8/4ohm

[orchardaudio]

All preorders have shipped.

Thank you for your support.

 

[David_M]

All preorders have shipped.

Thank you for your support.

Seriously ... do you have an orchard? If so, what type of fruit do you grow?

 

[orchardaudio]

Seriously ... do you have an orchard? If so, what type of fruit do you grow?

I grow nuts and pears.

 

[David_M]

The way my brain is wired is that once I saw your forum name, it was hard to read past "orchard"

 

[David_M]

Have you thought of modifying your amp design for multichannel uses? It'd be nice if it was possible to put 8 or 16 amplifier cards in one chassis to satisfy DTX or Dolby Atmos specifications for home audio theater. What would be involved in such a design? How would you implement it and still be cost-effective?

 

[Veri]

Have you thought of modifying your amp design for multichannel uses? It'd be nice if it was possible to put 8 or 16 amplifier cards in one chassis to satisfy DTX or Dolby Atmos specifications for home audio theater. What would be involved in such a design? How would you implement it and still be cost-effective?

Probably too niche though. As a smaller manufacturer everything needs to move and sell or Orchard will incur losses himself.

 

[orchardaudio]

Have you thought of modifying your amp design for multichannel uses? It'd be nice if it was possible to put 8 or 16 amplifier cards in one chassis to satisfy DTX or Dolby Atmos specifications for home audio theater. What would be involved in such a design? How would you implement it and still be cost-effective?

If an integrator wants to pursue something like this I am open to working with them.

 

[orchardaudio]

The rare moment when I get to enjoy my own products...
Qobuz --> Galaxy S10+ (BubbleUPnP) --> PecanPi Steamer (Volumio) --> Starkrimson Stereo Ultra --> Paradigm Monitor 9

My playlist for those interested:
https://open.qobuz.com/playlist/3288137

 

[orchardaudio]

Preorder pricing ends June 30th for the Starkrimson Stereo Ultra
https://orchardaudio.com/shop/ols/products/strkrmsn-str-ltr

 

[orchardaudio]

Just finished testing a production unit. Very happy with the results.

 

[David_M]

Congratulations on the nice and clean test report...One question though .... Is there a reason why the 32-tone test is at -25dB and not 0dB? I believe Amir tests at 0db, if I'm not mistaken, hence raises the noise a bit to truly determine the device effective bit-depth(ENOB) referenced to 0dB, as is the standard for ADCs and DACs.

Ditto for the 1MHz spectral plot, which is referenced to -40dB. Curious to see what level the switching frequency will be at...

Thanks!

 

[Koeitje]

Preorder pricing ends June 30th for the Starkrimson Stereo Ultra
https://orchardaudio.com/shop/ols/products/strkrmsn-str-ltr

View attachment 137501

I'm not a designer, but I would make the logo a little bit smaller. Give it some space to breathe.

 

[DSS]

I'm not a designer, but I would make the logo a little bit smaller. Give it some space to breathe.

That is only your perception. I perceive it as the trees in the orchard have space plenty to breath. And especially the speakers connected to it.

 

[orchardaudio]

I'm not a designer, but I would make the logo a little bit smaller. Give it some space to breathe.

If you look at all the purchase options, you will see there is option to purchase the amps with no logo at all.

 

[Zabloc]

Congratulations on the nice and clean test report...One question though .... Is there a reason why the 32-tone test is at -25dB and not 0dB? I believe Amir tests at 0db, if I'm not mistaken, hence raises the noise a bit to truly determine the device effective bit-depth(ENOB) referenced to 0dB, as is the standard for ADCs and DACs.

Ditto for the 1MHz spectral plot, which is referenced to -40dB. Curious to see what level the switching frequency will be at...

Thanks!

Can anyone answer this question, I am very interested?

 

[orchardaudio]

Can anyone answer this question, I am very interested?

So 0dB = 44.72Vrms which equates to 250W into 8ohms. Each tone cannot be at 44.72V because then the total power would way exceed 250W. So the sum of the powers of all tones is 250W which is why each tone is not at 0dB. @Amir must somehow compensate for this.

 

[orchardaudio]

Ditto for the 1MHz spectral plot, which is referenced to -40dB. Curious to see what level the switching frequency will be at...

https://www.audiosciencereview.com/...d-modules-starkrimson-ultra.18644/post-789630

 

[dougi]

So 0dB = 44.72Vrms which equates to 250W into 8ohms. Each tone cannot be at 44.72V because then the total power would way exceed 250W. So the sum of the powers of all tones is 250W which is why each tone is not at 0dB. @Amir must somehow compensate for this.

The multitone plot notes in the report indicate the "crest factor" (total peak to average ratio) due to multiple tones of about 13dB. This results in peak value of 13-3=10dB. Not sure why it seems to have peaks <-20dBFS though. Amir inhis probably just references to the top of each tone. You can that in REW as well for multitone and others by using the dBr scale. Play with the REW multitone generator to get a feel for these peak values. The more tones you use, the peak value actually gets less.

 

[David_M]

https://www.audiosciencereview.com/...d-modules-starkrimson-ultra.18644/post-789630

Thanks .... so why are the 2 spectral plots (one referenced above and one in the test report shown below) so different? I see much more distortion products at multiples of 1khz (before 20kHz) plus a much different (noisier) profile for the switching frequency by-products for the former spectral plot. I'm assuming these plots pertain to the exact same amplifier design.

Lastly, what are the 1-Watt and full-power bandwidths of this amp in 8 and 4 ohms. Is it also rated for 2 ohms operation?

 

[dougi]

The multitone plot notes in the report indicate the "crest factor" (total peak to average ratio) due to multiple tones of about 13dB. This results in peak value of 13-3=10dB. Not sure why it seems to have peaks <-20dBFS though. Amir inhis probably just references to the top of each tone. You can that in REW as well for multitone and others by using the dBr scale. Play with the REW multitone generator to get a feel for these peak values. The more tones you use, the peak value actually gets less.

To add, you have the adjusted crest factor of 10dB plus the RMS addition of the tones of 10*log(32)=15dB so 25dB total needs to be backed off from 0dBFS for each tone.