This Group Buy relates to this thread:
This is an interesting list, and I’ll keep updating it whenever someone expresses interest. Once we have 10 people, I’ll produce a batch.
1, Ricardxgf,
2, Extreme_Boky,
This is an interesting list, and I’ll keep updating it whenever someone expresses interest. Once we have 10 people, I’ll produce a batch.
1, Ricardxgf,
2, Extreme_Boky,
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Thanks for asking. My expected cost is $500 per unit due to the high BOM cost and the significant time and effort involved in making it. However, since you're showing the courage to try out this new stuff, I'd like to offer a 30% off, bringing the price down to $350 per unit!
Are you saying 1 unit as in a single channel or are you saying 1 unit as in a set for stereo?
Either way, I'm in for a stereo set.
Which PSU do you recommend?
1, Ricardxgf,
2, Extreme_Boky,
3, Uptownsquash
4, KaffiMann
Either way, I'm in for a stereo set.
Which PSU do you recommend?
1, Ricardxgf,
2, Extreme_Boky,
3, Uptownsquash
4, KaffiMann
Thank you for your interest! To clarify, 1 unit refers to a single-channel module. For a stereo amplifier, you will need 2 units. I have added the default number of units to the buying list, but please feel free to adjust or correct it as needed.
1, Ricardxgf, (2 units)
2, Extreme_Boky, (2 units)
3, Uptownsquash, (2 units)
4, KaffiMann, (2 units)
1, Ricardxgf, (2 units)
2, Extreme_Boky, (2 units)
3, Uptownsquash, (2 units)
4, KaffiMann, (2 units)
For the PSU, I would like to suggest the following two options. Both are PFC-enabled, fanless switch-mode power supplies. Please select the 48V version.
I also recommend using a separate power supply module for each channel. This not only delivers powerful sound output but also ensures perfect isolation between the two channels.
If using a single power supply, it is recommended to choose one with a power rating of at least 400W. Additionally, it is recommended to add a 470µF/100V capacitor at the power input of each module.
1, MEAN WELL 350W Slim Type with PFC Switching Power Supply
https://www.aliexpress.us/item/3256...t_main.20.671f1802yjBXI1&gatewayAdapt=glo2usa
2, TOPPCB 400W PFC Switching Power Supply
https://www.aliexpress.us/item/3256...ene:pcDetailBottomMoreOtherSeller|query_from:
I also recommend using a separate power supply module for each channel. This not only delivers powerful sound output but also ensures perfect isolation between the two channels.
If using a single power supply, it is recommended to choose one with a power rating of at least 400W. Additionally, it is recommended to add a 470µF/100V capacitor at the power input of each module.
1, MEAN WELL 350W Slim Type with PFC Switching Power Supply
https://www.aliexpress.us/item/3256...t_main.20.671f1802yjBXI1&gatewayAdapt=glo2usa
2, TOPPCB 400W PFC Switching Power Supply
https://www.aliexpress.us/item/3256...ene:pcDetailBottomMoreOtherSeller|query_from:
Nice design! This is the first Class D amp that looks like it was built like like aerospace milspec avionics with internal metal chambers to prevent RF leakage between stages. Very cool.
Is the final amp still “no feedback” Class D as the title suggests? All the block diagrams I have seen show a feedback loop.
Is the final amp still “no feedback” Class D as the title suggests? All the block diagrams I have seen show a feedback loop.
Hi Flmhhh,
Can you please summarize the specs on this thread so that we don’t have to distill it from the last thread? I have looked but still not clear to me if this is a zero feedback Class D amp and what is power, output impedance, THD specs, etc. I am even confused if it is a headphone amp or a speaker amp?
A block diagram or basic schematic would be nice to see (or is that proprietary?).
Thanks
Can you please summarize the specs on this thread so that we don’t have to distill it from the last thread? I have looked but still not clear to me if this is a zero feedback Class D amp and what is power, output impedance, THD specs, etc. I am even confused if it is a headphone amp or a speaker amp?
A block diagram or basic schematic would be nice to see (or is that proprietary?).
Thanks
I have demonstrated two projects in the thread under the Class D category. This thread, under ‘Group Buys,’ refers to the monoblock Class D amplifier, which shown as figure and it has the following specifications:
- Dimensions: 84mm (L) x 54mm (W) x 12mm (H)
- Modulation Mode: High-order differential sigma-delta modulator, 3.2MHz
- Idle Power: ~18W
- Power Voltage: 48V ±5%
- Output Stage Type: BTL only
- Rated Output Current: 15A
- Output Power: 100W RMS @ 8Ω, 200W RMS @ 4Ω
- Input: Balanced and single-ended (depending on the input connection configuration)
- Gain: 13dB / 26dB (configurable via switch)
- Distortion: Unknown yet; expecting less than 0.00x% across the entire audio bandwidth, please referring to the measurements of the headphone project, they shared the same modulator which I spent few years to fine tune.
The following is a brief block diagram outlining the amplifier module's architecture. Please understand that I cannot disclose further circuit details, as the PDM modulator is a proprietary design.
Within the PDM modulator, three feedback mechanisms are applied:
For anyone interested in a more technical discussion on the feedback, we can continue the conversation in the Class D thread.
Within the PDM modulator, three feedback mechanisms are applied:
- Negative feedback for the integrator.
- Positive feedback for hysteresis setting.
- Positive feedback for modulator oscillation.
For anyone interested in a more technical discussion on the feedback, we can continue the conversation in the Class D thread.
These are good technical summaries (specifications) to put on the first page of a GB vs making people look back at the technical thread, which may or may not have it clearly laid out.
That’s a very compact format and cool looking. $700 for a stereo pair is pricey without some measurements of the prototype at rated power or even at something like 25wrms though.
Thank you.
That’s a very compact format and cool looking. $700 for a stereo pair is pricey without some measurements of the prototype at rated power or even at something like 25wrms though.
Thank you.