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

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orchardaudio

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Performance in in mono mode (1 x SMPS1200A100 and 1 x Starkrimson Amp) 8-ohm load:
Bench_Mode_10W_8ohm.JPG CCIF Ratio vs Measured Level_8ohm.JPG FFT Spectrum_Mutitone_8ohm.JPG SMPTE Ratio vs Measured Level_8ohm.JPG Frequency_Response_8ohm.JPG THD+N Ratio vs Freq_8ohm.JPG THD+N Ratio vs Measured Level_8ohm.jpg Wideband FFT Spectrum -40dB Output_8ohm.JPG
 
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orchardaudio

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I have had a few requests to compare my modules to Ice Power 400A2 modules. Form their datasheet here:
https://icepower.dk/download/9283/, they have the following:
1621645245035.png

Here is the same exact test for Starkrimson Ultra 8-ohm load:
THD+N Ratio vs Measured Level_100_100_6670_8ohm_.JPG

Here is the same exact test for Starkrimson Ultra 4-ohm load:
THD+N Ratio vs Measured Level_100_100_6670_4ohm_.JPG
 

JohnYang1997

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Do you think the non-ultra version is better or the ultra version if power is not a concern? Similar?
 
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Do you think the non-ultra version is better or the ultra version if power is not a concern? Similar?

I would say if you have high sensitivity speakers like ~95dB and up, then the 150W will be better as it has better noise performance and lower gain.
 
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@orchardaudio
Wondering, would you say these sound/are better than your previous model, the standard Starkrimson?
I'm slightly confused by the specs in some areas seeming better than the prior (in the 20hz-20khz THD), but in others appearing slightly lesser (the 1kHz THD and notably SINAD 97 vs. 105). Should both be within the range of inaudible - but at the same time people round here do seem to make a point of those numbers...
I've often seen examples where a more powerful amp from the same company/range sacrifices fidelity, in the pursuit of power - which can of course be worth it if you need the power, to avoid clipping or the like.

Headroom can be very good to have, but I just wonder, if you don't strictly need the higher power, which would yield the best sound?

I know this might be a somewhat tough question to ask a maker - like picking your favorite child.

*I'm aware the notion these sorts of amps might sound audibly different might be contentious, so if anyone finds issue with the question, feel free to just move along... I'm just curious in case there is something to be said on the matter for the sake of being able to make the best purchase decision, given the prices aren't too different to deter me from picking either...
 
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@orchardaudio
Wondering, would you say these sound/are better than your previous model, the standard Starkrimson?
I'm slightly confused by the specs in some areas seeming better than the prior (in the 20hz-20khz THD), but in others appearing slightly lesser (the 1kHz THD and notably SINAD 97 vs. 105). Should both be within the range of inaudible - but at the same time people round here do seem to make a point of those numbers...
I've often seen examples where a more powerful amp from the same company/range sacrifices fidelity, in the pursuit of power - which can of course be worth it if you need the power, to avoid clipping or the like.

Headroom can be very good to have, but I just wonder, if you don't strictly need the higher power, which would yield the best sound?

I know this might be a somewhat tough question to ask a maker - like picking your favorite child.

Both amplifiers use my proprietary dual feedback modulator, the modulator is what mostly gives the amps the sound signature. So both amps will sound very much alike. I decided not to modify the modulator for the more powerful amps because the 150W ones got such rave reviews and now also received their second award.

In my opinion, you have to select the correct amp for the application and in the world of digital volume controls, you don't want to have too much headroom because you are then reducing your dynamic range by never using the amp's full power.

The 150W amps have a lower noise floor and lower gain so they fit much better with high sensitivity speakers of 92dB+ sensitivity in most applications.

I have a blog post on my website to help you choose the correct amp:
https://orchardaudio.com/blog/f/how-much-amplifier-power-do-i-need
 

Lord Victor

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Both amplifiers use my proprietary dual feedback modulator, the modulator is what mostly gives the amps the sound signature. So both amps will sound very much alike. I decided not to modify the modulator for the more powerful amps because the 150W ones got such rave reviews and now also received their second award.

In my opinion, you have to select the correct amp for the application and in the world of digital volume controls, you don't want to have too much headroom because you are then reducing your dynamic range by never using the amp's full power.

The 150W amps have a lower noise floor and lower gain so they fit much better with high sensitivity speakers of 92dB+ sensitivity in most applications.

I have a blog post on my website to help you choose the correct amp:
https://orchardaudio.com/blog/f/how-much-amplifier-power-do-i-need
Interesting! based on the calculations you mention, even my inefficient (low 80s, which is about as inefficient as it gets) speakers would reach about 96db with 150watts... so at that point I wonder if the trade off would be worth it to get closer to 100dB potential, considering even loud listening would usually only be about 85db...

interesting... weird about the convention about headroom, that I’m guessing is what caused th demand for an even more powerful amp, if even an inefficient speaker like that would actually have enough/ideal results in the original...
 
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Both amplifiers use my proprietary dual feedback modulator, the modulator is what mostly gives the amps the sound signature. So both amps will sound very much alike. I decided not to modify the modulator for the more powerful amps because the 150W ones got such rave reviews and now also received their second award.

In my opinion, you have to select the correct amp for the application and in the world of digital volume controls, you don't want to have too much headroom because you are then reducing your dynamic range by never using the amp's full power.

The 150W amps have a lower noise floor and lower gain so they fit much better with high sensitivity speakers of 92dB+ sensitivity in most applications.

I have a blog post on my website to help you choose the correct amp:
https://orchardaudio.com/blog/f/how-much-amplifier-power-do-i-need

Good to know, that is about what I suspected... in that case since even 150 watts, with its ability to handle 300w peaks, should be enough to blow my head off, even with an 88dB or lower efficiency speakers, I should just go for the less powerful one for the highest sound quality with these. If additional “headroom” above my listening level isn’t really a relevant thing.
I’d realistically mostly listen at 80dB assuming my phones calibrated measurements are completely off, so being able to play back at 100dB+ probably isn’t really relevant for the most part. Having that extra power might more so just be for “security” if one were to crank it some day I guess.
 

Lord Victor

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Good to know, that is about what I suspected... in that case since even 150 watts, with its ability to handle 300w peaks, should be enough to blow my head off, even with an 88dB or lower efficiency speakers, I should just go for the less powerful one for the highest sound quality with these. If additional “headroom” above my listening level isn’t really a relevant thing.
I’d realistically mostly listen at 80dB assuming my phones calibrated measurements are completely off, so being able to play back at 100dB+ probably isn’t really relevant for the most part. Having that extra power might more so just be for “security” if one were to crank it some day I guess.

True. I currently have some of my speakers in a bigger room, playing into a kitchen area, so with the much greater distance from the speakers I’d need much more power to compensate - probably for the best that I went for the Ultra modules then! Wouldn’t want fried tweeters along with my fried eggs when cooking!
I just hope I can actually get them - very interested to hear what all the GaN FET rave is about. If not now, I’ll have to re order them some other time. Fantastic customer service like this is something I want to support!
 
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orchardaudio

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For those that have ordered bare boards, orders have started shipping. Be on the lookout for an email from shippo (goshippo.com) with your tracking information.

For those that ordered completed modules orders will start shipping in about 2 to 3 weeks.

For those interested the preorder is now also open for the fully assembled and plug and play units here:
http://www.orchardaudio.com/shop/ols/products/strkrmsn-str-ltr
 
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Both amplifiers use my proprietary dual feedback modulator, the modulator is what mostly gives the amps the sound signature. So both amps will sound very much alike. I decided not to modify the modulator for the more powerful amps because the 150W ones got such rave reviews and now also received their second award.

In my opinion, you have to select the correct amp for the application and in the world of digital volume controls, you don't want to have too much headroom because you are then reducing your dynamic range by never using the amp's full power.

The 150W amps have a lower noise floor and lower gain so they fit much better with high sensitivity speakers of 92dB+ sensitivity in most applications.

I have a blog post on my website to help you choose the correct amp:
https://orchardaudio.com/blog/f/how-much-amplifier-power-do-i-need
Do you know why the Ultra Modules in the 20-20khz THD measurement specs appear to be slightly better, even at low power, than the lower power ones by the way? Seems counter-intuitive to me when the over all noise floor and sinad etc. are better on the lower power one, how this occurs? Seems almost like the Ultra's are better in some ways, but not in others, in terms of sheer cleanliness - wondering if your experience building the first ones have just lead to even better execution here, in spite of the higher power somehow, or if its something more simple?
 
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orchardaudio

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Do you know why the Ultra Modules in the 20-20khz THD measurement specs appear to be slightly better, even at low power, than the lower power ones by the way? Seems counter-intuitive to me when the over all noise floor and sinad etc. are better on the lower power one, how this occurs? Seems almost like the Ultra's are better in some ways, but not in others, in terms of sheer cleanliness - wondering if your experience building the first ones have just lead to even better execution here, in spite of the higher power somehow, or if its something more simple?

This behavior as I see it comes from two sources.
1. Inductors (the larger inductors have slightly better frequency characteristics)
2. Feedback (ultra has higher gain and therefore more feedback)

These two coupled together means that distortion does not increase as much as the frequency increases with the ultra amplifiers.
 

AudioJester

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What is the gain of this amp?

Edit: looked up specs 19dB

Thinking of upgrading some old ucd10s in my lx521.3 setup, for midrange drivers. But other amps are more standard 26dB gain. Would have to correct/match levels in my dsp pre.
 
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