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orchardaudio

orchardaudio

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Can you show wideband plot beyond 500 kHz

Here you go, it's from an older version of the amp but you will get a good idea.

64k Wideband FFT /w -40dB Output
FFT.jpg
 
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orchardaudio

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Another great write-up: 2 weeks with the Orchard Audio BOSC HiFi Monoblock Class-D GaN Amps
Before I go into any detail, let me say up front that these amps are something special. Detail and clarity galore with a transparency that grabs your attention and doesn't let go. The amps run cool to the touch and are so small that they can be easily stashed away out of site in any system. In my opinion, they punch way above their price point and easily turn a background music system into something that cannot be easily ignored... or at least, that was my experience.
 
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orchardaudio

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One more: https://www.audionervosa.com/index.php?topic=7264.msg91698#msg91698
This is an extremely good amplifier, something I could live with easily if I didn't own the Modulus 286. The noise floor is very low, and you hear tiny details into the background on many recordings. The amplifier is very similar sounding to the Modulus 286 which is a major compliment! Big, bombastic dynamics, excellent tight very well delineated bass and yes, ethereal high end. Soundstaging was wide, and performers were well placed, such that you could easily distinguish the differences between them.*
 

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I TRUST in the subjective review made by Anand, who I read for years in others forums (Audiocircle and Diyaudio). Putting your first amplifier at the level of Modulus 286 (by Tom Christiansen) is very worthwhile for you.

Based on the Asgard's spec of 0.2ohm output impedance it will have no issue with driving BOSC.

BOSC has best performance in the 10 to 25W range so it will pair well with the 95dB speakers. This is exactly what Anand had.

From the graphs that you have published it seems that it does very well also at greater power, because the difference in distortion is very small.

As for the heat, being the power supply in another module it is assumed that it does not get very hot due to the great efficiency, although it would not hurt to measure the temperature with the stressed amplifier.

Except for Purifi, all the amplification modules that have caught my attention these years are sold from the US, which is a nuisance living in Spain :confused:

If I lived in NY I would go to your demonstration, bringing my own selection of music, very different and demanding with the amplifiers and speakers.

Good luck with your business adventure.
 
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Eljimador

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@orchardaudio - Your web page for Bosc says it will have two options for gain — e.g. “Gain: 16.8dB or 6.92 (For 8 and 6Ω speakers)”. How is the gain adjusted - does it involve opening the case?
Also, you’ve said there are two different versions of the amps: a 4-ohm version and an 8-ohm version. I don’t think I’ve seen that before with solid-state equipment, although I believe some tube amps have different output taps for different speaker impedance. Can you explain the reasons for creating two versions and whether the 4-ohm version would perform suboptimally with higher-impedance speakers (say, if a user changed equipment in the future)?
 
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orchardaudio

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@orchardaudio - Your web page for Bosc says it will have two options for gain — e.g. “Gain: 16.8dB or 6.92 (For 8 and 6Ω speakers)”. How is the gain adjusted - does it involve opening the case?
Also, you’ve said there are two different versions of the amps: a 4-ohm version and an 8-ohm version. I don’t think I’ve seen that before with solid-state equipment, although I believe some tube amps have different output taps for different speaker impedance. Can you explain the reasons for creating two versions and whether the 4-ohm version would perform suboptimally with higher-impedance speakers (say, if a user changed equipment in the future)?

The 4 ohm version of the amp will have lower gain and higher input impedance. Both amplifiers are identical otherwise.

Either can be used with 4 or 8 ohm speakers.

The amps will come with the gain set, it is not adjustable by the user.

If you want to use the amp with the higher gain for 4 ohm speakers you can, but you have to ensure no voltage above 3.75Vrms (~170W) on the input. In the review quoted above, Anand used the higher gain version with 4 ohm speakers, but since his speakers are 96dB efficient he was maxing out at 15-20W.
I TRUST in the subjective review made by Anand, who I read for years in others forums (Audiocircle and Diyaudio). Putting your first amplifier at the level of Modulus 286 (by Tom Christiansen) is very worthwhile for you.

You can also use the lower gain amp with 8 ohm speakers but realize you will need 7Vrms on the input to get the amp to 150W.
 

Eljimador

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If you want to use the amp with the higher gain for 4 ohm speakers you can, but you have to ensure no voltage above 3.75Vrms (~170W) on the input.
I assume these are made to pair with PecanPi, which has 5Vrms max output on XLR. So the 8 ohm amp with 16.8dB gain will avoid clipping at 5Vrms input, driving a 6 ohm (or 8 ohm) load, and the 4 ohm amp with 13.8dB is needed in order to use the full output of PecanPi into a 4 ohm load without clipping?
[EDIT: Just did the math and the 16.8dB version does indeed give 150W at 5V input into 8 ohms, while the 13.8 dB version gives 150W at 5V into 4ohms. 150W is the rated power of the amp, although I don’t see an impedance given. With the 16.8dB version you get should 200W into 6 ohms at 5V, while the 13.8 dB version would only put out 100W into that load. So, may I assume no issues with 200W into 6 ohms?]
 
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orchardaudio

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So, may I assume no issues with 200W into 6 ohms?]

No issues.

I assume these are made to pair with PecanPi, which has 5Vrms max output on XLR.
While the BOSC amp was designed with the PecanPi in mind, that in no way means that it cannot work with other equipment (DACs, pre-amps, etc).
 

Eljimador

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No issues.


While the BOSC amp was designed with the PecanPi in mind, that in no way means that it cannot work with other equipment (DACs, pre-amps, etc).
Thanks for the responses.
And I didn’t mean to suggest there would be any problem mixing and matching with other equipment — just that the gain settings of Bosc logically should be a good fit with the output of PecanPi. And it happens that I have a PecanPi...
 
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orchardaudio

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BOSC quality...

Every BOSC amp is hand-assembled and tested in the USA, by yours truly.

The circuit board (PCB) uses a high-quality dielectric, has a gold finish (ENIG), and is assembled in Eatontown, NJ.

The components all come from high-end semiconductor manufacturers: Texas Instruments; Analog Devices; Murata; Panasonic; and NXP; to name a few.

The output filter inductors use oxygen-free copper (OFC) and are specifically made for Class-D amplifiers.

Even though Orchard Audio is new to the market, I have multiple patents and over a decade of experience in designing audio electronics.

I believe that you will be very happy with both the sound and quality of BOSC amplifiers.

Contact me with any questions!

https://www.kickstarter.com/projects/orchardaudio/bosctm-hifi-monoblock-audio-amplifier?ref=1hvtb6
 
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orchardaudio

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I was, unfortunately, unable to reach the BOSC Kickstarter goal.

The good news is that there is another chance to get your hands on the BOSC amplifiers! I hope that you will support Orchard Audio and preorder BOSC directly through the website, here:
https://orchardaudio.com/shop?olsPage=products/bsc-mplfr

The preorders are available at $999 (33% off MSRP), for a pair of amps.

Once 40 preorders are placed, I will start manufacturing the BOSC amplifiers, and shipments will start 8-12 weeks after that.

Pricing is as follows:
$999 for the first 40 preorders
$1099 for orders 41 through 60
$1199 for orders 61 and up
 
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