• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Fosi Audio TB10D teardown and review

Pixelwarfare

Member
Joined
Oct 3, 2022
Messages
16
Likes
40
Fosi Audio TB10D teardown and review

The packaging:
NL68CtdwmP3a_lTPh8RSoJn-bq9RjcPRpzGjsH_RENyVTS8khbPqRbvan-NT5QiFkcujkTmkQjP91N08h8wrbwPgClMaUHDEtIvRq1ES1mXoOBMOWJIB5iwwXIC1IRSrx3vfkfohCyhKh7_h6L9ZWeGGGb4WPOaFr4bKQVb-mj6Whf5WYH57DIRoxNpC

Front:
N1hEiK0Ah5W-jg_utBjspAHrUTN7lWmNOZiS2cQIP9pMehK3Ca2UpMjygUNbK-sbTcpegiuMMtP8CFSoaRvMdQgDGOklXh6CkE0lrqf5gjrdPC5akAy0qvtzfwJQrvjVMZT1KfoG3TwGKVyZzaT2fMwcqZaGLy6nPadrQCRjHcZ3fQgUq6SQceIcFhNr


Back:
vcCc_D08is8U5qxmeFLkNi0M_QfpktM8lxwmZW4S1wn4_VfAlTmxktCZaRAUvC1AmUaUHW3-6M3cbjrzYG7wlYKz7cIh7YaNgobEpyUazKXknsQEY27Z5JY6v5KBKPpuYYCbGM_mShyVtKz0HdytfwzTrfNZANxb5gc-Rt-cvA6kKXcop545zLu61vLf


Teardown:
BHHVkXynoAkJbwda7jt_zPL-K5B_u3yhPX23vO3D0pL5vnYDelU1BHy1pDSRcXMqLyIkAJ2h24cvYsVbaV0fd4I02BD3E7r_BPArnvziho7AVcNwGSSzRpcfpgGEOfR705eqbzQlUYOdvW3K-2vNLZ4T-wn-RJQwGsayZJy4oRSXNVrETeWQ-pfhNv8x

WKiVzHQQ6VFzzsmfTB1OGwufaL9NyoBWOFQrz5UOJKUsG0in-MYI_f8KFUtb9ELqv-J7jI6fECIDRBkT3kC_J6Q1KeN8LFjsVhXJETk28uEdi6jqUWdQEQu2KYjsfK6-cfpzyIncJ3g3BzjMYKPVfda2OBvu9Ba9DzNHyt3LvFTjg9qaOUG8xGxcO8gD
1jQi2jQqjag9uaUXhPXY_cll88zCuCjV3_sCYc2KFSu85-8gm5uorU2WQNhHhmoxBUec6VEvJJEiqjWaSzQC7kTvObU7zfa9r22yZTgsC2dcEv94NiEEc2U5NQ1C7t2XZb_Vi0_p-6q6bIS_9BsEiyQ00ncyHWcycziu7ja5vrNYsL9nuljIQ4cIB9Mz


TPA3255 chip under the heatsink:
bwHdlkqGeey4Hs1_mmbMuVq_ptF8wujnnU2wFKmFeb27l6VNJVrEHuVHVxQX5whCnfLvUkRF09wQqXniyVbNeGHm0C0UasQsTvZvxiDbWboJgzIClco4FB3BAU7fmznERPuMLnclHxCP11KT0-e9XHZ_DI8mJAxhQsmBEIjWIfOR6rzrmM-c58GETUjF


Thermography on dummy loads (4ohm):
tHc68JouctTe2KTAFftAT3SPvlKw_UPD7NzXvhVgJqWF5fUlgtl-VmnzOvfMRNQUjDRYxoA6oUx-D1J77ATyGf-EYYPM36bQC35xLMEpJB17qYSsij5WoU3AFfIt6SyiBw7M6YK6PQW9ux5WHNgqDZwdMSwVScHh3xXcFEHtNheLpyc8EsTHnxlWy2Nj


Heat issue:

One thing that is not often discussed regarding mini class-D amps is thermal management. I was planning to delve further into this issue. I encountered multiple thermal protections being triggered on the chip while using it at full power (160w rms 2ch) on 4 ohm loads for about 5 minutes. The enclosure was warm, but not hot. However, when I ran the amp again with the PCB exposed, I was able to measure the temperature of the aluminum heatsink.

The aluminum heatsink has a reflective surface, making it difficult to measure. I placed a volume knob on top of the fin to absorb the heat, since the volume knob has a black matte surface and is not polished, its emissivity can be picked up by a FLIR imaging device.

Another technique I used was putting 2 drops of distilled water between the heatsink fins. The water has excellent emissivity and will heat up until it boils into vapor, allowing me to accurately measure the temperature until it reaches above 100C or dried up. As you can see in the picture below, the heatsink was extremely hot (85C). Imagine what it would be like if it were enclosed in a sealed enclosure.

Since heat is the number one enemy of all electrical components, cramming all the heat inside the enclosure will not make the components last. For example, the capacitor will have a short lifespan.

If you only listen to music casually, you probably don't need to worry much about the lifespan of the components. However, if you are constantly blasting your ears with loud music, don't expect the components to last for a long time.

Since this issue is widespread and not just limited to one manufacturer, I hope that manufacturers will incorporate some form of active thermal management or improve their enclosure designs to address this problem. Hint: use the casing as a heatsink!

86.6C is the temperature of distilled water trapped between aluminum fins. I didn't have the opportunity to measure the temperature directly above the chip with water because it evaporates rapidly. I assume it was over 100C.

Nqaf2e3ptiabs3-RQQDburkrxgGns3bb0xv1usjwg3i2Oiy-GmYVGh7bZ8_BpIGwLHZuOd3gj1EGcSvYB-7PcCJBiR4C5MFxDly03PvxDXZKCelWjmmAuaA56rRR8l7IWfDpzgxt0c14tSx-G_rPxP8HZqX8djNRPKkrHz3qbsGKrRaDapGRaO1A9YzN

Matt black alu volume knob have much better emissivity to be picked up.
F1MA63mUa9ZuzSqJZvpvhVghypJhI22kbbqyrmx8ZKDpJRzxQFP-kqvkTn_u1de2RZ65qF9EFQJef0nJO6iCcfDDnT4fRM3jSO915mhHS9Vv5n0JOLBmD_XU5NUN1i0dha6g6C5MnkRvQ1etpfKYtBWayHDermEIQhGC0mp0lZmMVVzu6e5rRJHuOgZk
cKW5uly0Z2DdcK2bukkSE7VqwGWIRdDVW7sKmz4OneOEV07dKBrNz5rkyMPyrfI7Y3qQyBw_4Jsrau_fFojZYGpO3ijvYPnLgiH0ORV8G4qO8AUOtFQaQnCVfwveKa6CHBVyodKXTkRHX7IhCBAtoGS6fJZy9d-GjH8Tw_lrteJsWybBHlwZI4aLioEJ



How does it sound?

I conducted a comparison between the Onkyo RZ50 in pure output mode (RCA) and the BT30D Pro (RCA), both using RP5000F towers and an amp selector switch. I was unable to hear any difference between them, which is good news. It appears that the well-implemented TPA3255 chip sounds the same in all cases.

Same 32V-5A adapter used for multiple models.
7-qCKnEVzgXcBhEIefNtKbxnfm6ATCX8Iw8lnPADuLtqCDCml-llMCm2JklJA6T9aNZeCM5NPWuDJdjlU-qIh0jYNScWNUVEIbgcZUxFWl91H9rYkuWa5cMDkVU_l7Qq4BiZBQtZXrCbpDGazXPOnyIfYBNAHS-3Tr65pqEqpXsVDWRHgPcm1kBSo3CX


Everytime I plugged in the male power plug, there were sparks. I can see and hear it.


The power measurement:

Setup:
RCA Input signal @ 1000hz, 1Vrms
Tone control at half way

L & R both driven, 8 ohm load, 50W rms per channel, before clipping. Volume knob at 2.5 o’clock
1R3S1NbT0VNY8ApIgHuSMrxjVMruc_sek5hFlWNdM3btWrHPo7J7fp7Uz-LlrT8x8rz-zNC3a5eX1mbaZyG-IZgQPzlfztMOo69Z783BBGtkyPUbX_x3ygjit86A9dwK5LZQoL1mrRGru1KxcPK1dx0aKLa8eg8KbE5IqQgNK9cobzlXDfPl4dUsif02


L & R both driven, 8 ohm load, 60W rms per channel, clipping, Volume knob at 3 o'clock
o8_bO-NbwEYh51o9YpNYJp0Nbv8_VcuY3JnpMz1tIGrekTV_zyMOS1gDROCJElNbjd05XMAe8Zfq3qhhC2Tnqd_3fqU7yH4zhy8VRD3FUzCaDPrZD6F2bx_BZ3JcIl8tYOzcHDo3jGdE8f83TpCoGczCeWrVb8yX2x4NLX0ZdKo_3TIf5gobyJHwUVbH


L & R both driven, 4 ohm load, 85W rms per channel, before clipping. Volume knob at 2.5 o’clock
U2rAoMJdJoMpgW4fNfHl5hJUhtDuDCXq6SgUZvPCnj6Ibyql_xmK4r1m8Wj6SGBhkqOrQT09vcWWfPDOQP46kn1gqsyGS3YI9ge9EgrW3zmqADzamZN3bks03mxDXTEkxXs6wILXFEO1xtIGwAcV6z6X9Gw_wTapU3TwTpZTOzWkBNZAZWDvhSpt0G3I


I wasn't able to reach clipping at 4 ohm load. Either the amp or power adapter goes into OCP protect mode everytime.


Noise was tested at maximum volume. There was a barely audible hiss from the speakers, which could only be heard if you put your ear close to the tweeter. There is no circuit to shut off the signal because it is not audible when sitting away from the speakers.

0jBb6z-qLyKvm4HK4hF0h3VEoYaTfwrqS6Z88oMmMqO-YXxj-ghJlad3UHEbm_quKadufNlCEETV48S2oX_ku5Q36sQe2XCA3DZGKAqFKAHdIVMvh2pm2HLBP5iUZYvdpKBU67UVOZQIXXf5rAYwqvHjXNJaTXkXs1f9W3nVazGJcqRp0CQ7k03NGwRL


The TPA3255 chips are efficient and can produce a significant amount of power for their size.. You can increase the power output of these chips by upgrading upto 48V power adapter. However, because on the heat issue, I wouldn't do it unless you modify the enclosure with active cooling.

It appears that many manufacturers using this chip have set their power limits based on the capabilities of the power adapter.


Pros:
  • Great build quality
  • Excellent sound quality, to my ear it’s on par with the RZ50 and BT30D Pro
  • Low noise floor
  • Excellent price / performance ratio

Cons:
  • Thermal management
  • Sparks
 
Last edited:

Jacob8275

Member
Joined
Oct 6, 2022
Messages
37
Likes
23
Thank you for your review, it's a great little amp for this low price, I have one but no sparks issues.
 

Schlippwhip68

Addicted to Fun and Learning
Joined
Nov 28, 2020
Messages
511
Likes
198
Location
Essex, UK.
Fosi Audio TB10D teardown and review

The packaging:
NL68CtdwmP3a_lTPh8RSoJn-bq9RjcPRpzGjsH_RENyVTS8khbPqRbvan-NT5QiFkcujkTmkQjP91N08h8wrbwPgClMaUHDEtIvRq1ES1mXoOBMOWJIB5iwwXIC1IRSrx3vfkfohCyhKh7_h6L9ZWeGGGb4WPOaFr4bKQVb-mj6Whf5WYH57DIRoxNpC

Front:
N1hEiK0Ah5W-jg_utBjspAHrUTN7lWmNOZiS2cQIP9pMehK3Ca2UpMjygUNbK-sbTcpegiuMMtP8CFSoaRvMdQgDGOklXh6CkE0lrqf5gjrdPC5akAy0qvtzfwJQrvjVMZT1KfoG3TwGKVyZzaT2fMwcqZaGLy6nPadrQCRjHcZ3fQgUq6SQceIcFhNr


Back:
vcCc_D08is8U5qxmeFLkNi0M_QfpktM8lxwmZW4S1wn4_VfAlTmxktCZaRAUvC1AmUaUHW3-6M3cbjrzYG7wlYKz7cIh7YaNgobEpyUazKXknsQEY27Z5JY6v5KBKPpuYYCbGM_mShyVtKz0HdytfwzTrfNZANxb5gc-Rt-cvA6kKXcop545zLu61vLf


Teardown:
BHHVkXynoAkJbwda7jt_zPL-K5B_u3yhPX23vO3D0pL5vnYDelU1BHy1pDSRcXMqLyIkAJ2h24cvYsVbaV0fd4I02BD3E7r_BPArnvziho7AVcNwGSSzRpcfpgGEOfR705eqbzQlUYOdvW3K-2vNLZ4T-wn-RJQwGsayZJy4oRSXNVrETeWQ-pfhNv8x

WKiVzHQQ6VFzzsmfTB1OGwufaL9NyoBWOFQrz5UOJKUsG0in-MYI_f8KFUtb9ELqv-J7jI6fECIDRBkT3kC_J6Q1KeN8LFjsVhXJETk28uEdi6jqUWdQEQu2KYjsfK6-cfpzyIncJ3g3BzjMYKPVfda2OBvu9Ba9DzNHyt3LvFTjg9qaOUG8xGxcO8gD
1jQi2jQqjag9uaUXhPXY_cll88zCuCjV3_sCYc2KFSu85-8gm5uorU2WQNhHhmoxBUec6VEvJJEiqjWaSzQC7kTvObU7zfa9r22yZTgsC2dcEv94NiEEc2U5NQ1C7t2XZb_Vi0_p-6q6bIS_9BsEiyQ00ncyHWcycziu7ja5vrNYsL9nuljIQ4cIB9Mz


TPA3255 chip under the heatsink:
bwHdlkqGeey4Hs1_mmbMuVq_ptF8wujnnU2wFKmFeb27l6VNJVrEHuVHVxQX5whCnfLvUkRF09wQqXniyVbNeGHm0C0UasQsTvZvxiDbWboJgzIClco4FB3BAU7fmznERPuMLnclHxCP11KT0-e9XHZ_DI8mJAxhQsmBEIjWIfOR6rzrmM-c58GETUjF


Thermography on dummy loads (4ohm):
tHc68JouctTe2KTAFftAT3SPvlKw_UPD7NzXvhVgJqWF5fUlgtl-VmnzOvfMRNQUjDRYxoA6oUx-D1J77ATyGf-EYYPM36bQC35xLMEpJB17qYSsij5WoU3AFfIt6SyiBw7M6YK6PQW9ux5WHNgqDZwdMSwVScHh3xXcFEHtNheLpyc8EsTHnxlWy2Nj


Heat issue:

One thing that is not often discussed regarding mini class-D amps is thermal management. I was planning to delve further into this issue. I encountered multiple thermal protections being triggered on the chip while using it at full power (160w rms 2ch) on 4 ohm loads for about 5 minutes. The enclosure was warm, but not hot. However, when I ran the amp again with the PCB exposed, I was able to measure the temperature of the aluminum heatsink.

The aluminum heatsink has a reflective surface, making it difficult to measure. I placed a volume knob on top of the fin to absorb the heat, since the volume knob has a black matte surface and is not polished, its emissivity can be picked up by a FLIR imaging device.

Another technique I used was putting 2 drops of distilled water between the heatsink fins. The water has excellent emissivity and will heat up until it boils into vapor, allowing me to accurately measure the temperature until it reaches above 100C or dried up. As you can see in the picture below, the heatsink was extremely hot (85C). Imagine what it would be like if it were enclosed in a sealed enclosure.

Since heat is the number one enemy of all electrical components, cramming all the heat inside the enclosure will not make the components last. For example, the capacitor will have a short lifespan.

If you only listen to music casually, you probably don't need to worry much about the lifespan of the components. However, if you are constantly blasting your ears with loud music, don't expect the components to last for a long time.

Since this issue is widespread and not just limited to one manufacturer, I hope that manufacturers will incorporate some form of active thermal management or improve their enclosure designs to address this problem. Hint: use the casing as a heatsink!

86.6C is the temperature of distilled water trapped between aluminum fins. I didn't have the opportunity to measure the temperature directly above the chip with water because it evaporates rapidly. I assume it was over 100C.

Nqaf2e3ptiabs3-RQQDburkrxgGns3bb0xv1usjwg3i2Oiy-GmYVGh7bZ8_BpIGwLHZuOd3gj1EGcSvYB-7PcCJBiR4C5MFxDly03PvxDXZKCelWjmmAuaA56rRR8l7IWfDpzgxt0c14tSx-G_rPxP8HZqX8djNRPKkrHz3qbsGKrRaDapGRaO1A9YzN

Matt black alu volume knob have much better emissivity to be picked up.
F1MA63mUa9ZuzSqJZvpvhVghypJhI22kbbqyrmx8ZKDpJRzxQFP-kqvkTn_u1de2RZ65qF9EFQJef0nJO6iCcfDDnT4fRM3jSO915mhHS9Vv5n0JOLBmD_XU5NUN1i0dha6g6C5MnkRvQ1etpfKYtBWayHDermEIQhGC0mp0lZmMVVzu6e5rRJHuOgZk
cKW5uly0Z2DdcK2bukkSE7VqwGWIRdDVW7sKmz4OneOEV07dKBrNz5rkyMPyrfI7Y3qQyBw_4Jsrau_fFojZYGpO3ijvYPnLgiH0ORV8G4qO8AUOtFQaQnCVfwveKa6CHBVyodKXTkRHX7IhCBAtoGS6fJZy9d-GjH8Tw_lrteJsWybBHlwZI4aLioEJ



How does it sound?

I conducted a comparison between the Onkyo RZ50 in pure output mode (RCA) and the BT30D Pro (RCA), both using RP5000F towers and an amp selector switch. I was unable to hear any difference between them, which is good news. It appears that the well-implemented TPA3255 chip sounds the same in all cases.

Same 32V-5A adapter used for multiple models.
7-qCKnEVzgXcBhEIefNtKbxnfm6ATCX8Iw8lnPADuLtqCDCml-llMCm2JklJA6T9aNZeCM5NPWuDJdjlU-qIh0jYNScWNUVEIbgcZUxFWl91H9rYkuWa5cMDkVU_l7Qq4BiZBQtZXrCbpDGazXPOnyIfYBNAHS-3Tr65pqEqpXsVDWRHgPcm1kBSo3CX


Everytime I plugged in the male power plug, there were sparks. I can see and hear it.


The power measurement:

Setup:
RCA Input signal @ 1000hz, 1Vrms
Tone control at half way

L & R both driven, 8 ohm load, 50W rms per channel, before clipping. Volume knob at 2.5 o’clock
1R3S1NbT0VNY8ApIgHuSMrxjVMruc_sek5hFlWNdM3btWrHPo7J7fp7Uz-LlrT8x8rz-zNC3a5eX1mbaZyG-IZgQPzlfztMOo69Z783BBGtkyPUbX_x3ygjit86A9dwK5LZQoL1mrRGru1KxcPK1dx0aKLa8eg8KbE5IqQgNK9cobzlXDfPl4dUsif02


L & R both driven, 8 ohm load, 60W rms per channel, clipping, Volume knob at 3 o'clock
o8_bO-NbwEYh51o9YpNYJp0Nbv8_VcuY3JnpMz1tIGrekTV_zyMOS1gDROCJElNbjd05XMAe8Zfq3qhhC2Tnqd_3fqU7yH4zhy8VRD3FUzCaDPrZD6F2bx_BZ3JcIl8tYOzcHDo3jGdE8f83TpCoGczCeWrVb8yX2x4NLX0ZdKo_3TIf5gobyJHwUVbH


L & R both driven, 4 ohm load, 85W rms per channel, before clipping. Volume knob at 2.5 o’clock
U2rAoMJdJoMpgW4fNfHl5hJUhtDuDCXq6SgUZvPCnj6Ibyql_xmK4r1m8Wj6SGBhkqOrQT09vcWWfPDOQP46kn1gqsyGS3YI9ge9EgrW3zmqADzamZN3bks03mxDXTEkxXs6wILXFEO1xtIGwAcV6z6X9Gw_wTapU3TwTpZTOzWkBNZAZWDvhSpt0G3I


I wasn't able to reach clipping at 4 ohm load. Either the amp or power adapter goes into OCP protect mode everytime.


Noise was tested at maximum volume. There was a barely audible hiss from the speakers, which could only be heard if you put your ear close to the tweeter. There is no circuit to shut off the signal because it is not audible when sitting away from the speakers.

0jBb6z-qLyKvm4HK4hF0h3VEoYaTfwrqS6Z88oMmMqO-YXxj-ghJlad3UHEbm_quKadufNlCEETV48S2oX_ku5Q36sQe2XCA3DZGKAqFKAHdIVMvh2pm2HLBP5iUZYvdpKBU67UVOZQIXXf5rAYwqvHjXNJaTXkXs1f9W3nVazGJcqRp0CQ7k03NGwRL


The TPA3255 chips are efficient and can produce a significant amount of power for their size.. You can increase the power output of these chips by upgrading upto 48V power adapter. However, because on the heat issue, I wouldn't do it unless you modify the enclosure with active cooling.

It appears that many manufacturers using this chip have set their power limits based on the capabilities of the power adapter.


Pros:
  • Great build quality
  • Excellent sound quality, to my ear it’s on par with the RZ50 and BT30D Pro
  • Low noise floor
  • Excellent price / performance ratio

Cons:
  • Thermal management
  • Sparks
IMG_0601.jpeg

The heat is real which is why i did this to my A07.
 

Schlippwhip68

Addicted to Fun and Learning
Joined
Nov 28, 2020
Messages
511
Likes
198
Location
Essex, UK.
Fosi Audio TB10D teardown and review

The packaging:
NL68CtdwmP3a_lTPh8RSoJn-bq9RjcPRpzGjsH_RENyVTS8khbPqRbvan-NT5QiFkcujkTmkQjP91N08h8wrbwPgClMaUHDEtIvRq1ES1mXoOBMOWJIB5iwwXIC1IRSrx3vfkfohCyhKh7_h6L9ZWeGGGb4WPOaFr4bKQVb-mj6Whf5WYH57DIRoxNpC

Front:
N1hEiK0Ah5W-jg_utBjspAHrUTN7lWmNOZiS2cQIP9pMehK3Ca2UpMjygUNbK-sbTcpegiuMMtP8CFSoaRvMdQgDGOklXh6CkE0lrqf5gjrdPC5akAy0qvtzfwJQrvjVMZT1KfoG3TwGKVyZzaT2fMwcqZaGLy6nPadrQCRjHcZ3fQgUq6SQceIcFhNr


Back:
vcCc_D08is8U5qxmeFLkNi0M_QfpktM8lxwmZW4S1wn4_VfAlTmxktCZaRAUvC1AmUaUHW3-6M3cbjrzYG7wlYKz7cIh7YaNgobEpyUazKXknsQEY27Z5JY6v5KBKPpuYYCbGM_mShyVtKz0HdytfwzTrfNZANxb5gc-Rt-cvA6kKXcop545zLu61vLf


Teardown:
BHHVkXynoAkJbwda7jt_zPL-K5B_u3yhPX23vO3D0pL5vnYDelU1BHy1pDSRcXMqLyIkAJ2h24cvYsVbaV0fd4I02BD3E7r_BPArnvziho7AVcNwGSSzRpcfpgGEOfR705eqbzQlUYOdvW3K-2vNLZ4T-wn-RJQwGsayZJy4oRSXNVrETeWQ-pfhNv8x

WKiVzHQQ6VFzzsmfTB1OGwufaL9NyoBWOFQrz5UOJKUsG0in-MYI_f8KFUtb9ELqv-J7jI6fECIDRBkT3kC_J6Q1KeN8LFjsVhXJETk28uEdi6jqUWdQEQu2KYjsfK6-cfpzyIncJ3g3BzjMYKPVfda2OBvu9Ba9DzNHyt3LvFTjg9qaOUG8xGxcO8gD
1jQi2jQqjag9uaUXhPXY_cll88zCuCjV3_sCYc2KFSu85-8gm5uorU2WQNhHhmoxBUec6VEvJJEiqjWaSzQC7kTvObU7zfa9r22yZTgsC2dcEv94NiEEc2U5NQ1C7t2XZb_Vi0_p-6q6bIS_9BsEiyQ00ncyHWcycziu7ja5vrNYsL9nuljIQ4cIB9Mz


TPA3255 chip under the heatsink:
bwHdlkqGeey4Hs1_mmbMuVq_ptF8wujnnU2wFKmFeb27l6VNJVrEHuVHVxQX5whCnfLvUkRF09wQqXniyVbNeGHm0C0UasQsTvZvxiDbWboJgzIClco4FB3BAU7fmznERPuMLnclHxCP11KT0-e9XHZ_DI8mJAxhQsmBEIjWIfOR6rzrmM-c58GETUjF


Thermography on dummy loads (4ohm):
tHc68JouctTe2KTAFftAT3SPvlKw_UPD7NzXvhVgJqWF5fUlgtl-VmnzOvfMRNQUjDRYxoA6oUx-D1J77ATyGf-EYYPM36bQC35xLMEpJB17qYSsij5WoU3AFfIt6SyiBw7M6YK6PQW9ux5WHNgqDZwdMSwVScHh3xXcFEHtNheLpyc8EsTHnxlWy2Nj


Heat issue:

One thing that is not often discussed regarding mini class-D amps is thermal management. I was planning to delve further into this issue. I encountered multiple thermal protections being triggered on the chip while using it at full power (160w rms 2ch) on 4 ohm loads for about 5 minutes. The enclosure was warm, but not hot. However, when I ran the amp again with the PCB exposed, I was able to measure the temperature of the aluminum heatsink.

The aluminum heatsink has a reflective surface, making it difficult to measure. I placed a volume knob on top of the fin to absorb the heat, since the volume knob has a black matte surface and is not polished, its emissivity can be picked up by a FLIR imaging device.

Another technique I used was putting 2 drops of distilled water between the heatsink fins. The water has excellent emissivity and will heat up until it boils into vapor, allowing me to accurately measure the temperature until it reaches above 100C or dried up. As you can see in the picture below, the heatsink was extremely hot (85C). Imagine what it would be like if it were enclosed in a sealed enclosure.

Since heat is the number one enemy of all electrical components, cramming all the heat inside the enclosure will not make the components last. For example, the capacitor will have a short lifespan.

If you only listen to music casually, you probably don't need to worry much about the lifespan of the components. However, if you are constantly blasting your ears with loud music, don't expect the components to last for a long time.

Since this issue is widespread and not just limited to one manufacturer, I hope that manufacturers will incorporate some form of active thermal management or improve their enclosure designs to address this problem. Hint: use the casing as a heatsink!

86.6C is the temperature of distilled water trapped between aluminum fins. I didn't have the opportunity to measure the temperature directly above the chip with water because it evaporates rapidly. I assume it was over 100C.

Nqaf2e3ptiabs3-RQQDburkrxgGns3bb0xv1usjwg3i2Oiy-GmYVGh7bZ8_BpIGwLHZuOd3gj1EGcSvYB-7PcCJBiR4C5MFxDly03PvxDXZKCelWjmmAuaA56rRR8l7IWfDpzgxt0c14tSx-G_rPxP8HZqX8djNRPKkrHz3qbsGKrRaDapGRaO1A9YzN

Matt black alu volume knob have much better emissivity to be picked up.
F1MA63mUa9ZuzSqJZvpvhVghypJhI22kbbqyrmx8ZKDpJRzxQFP-kqvkTn_u1de2RZ65qF9EFQJef0nJO6iCcfDDnT4fRM3jSO915mhHS9Vv5n0JOLBmD_XU5NUN1i0dha6g6C5MnkRvQ1etpfKYtBWayHDermEIQhGC0mp0lZmMVVzu6e5rRJHuOgZk
cKW5uly0Z2DdcK2bukkSE7VqwGWIRdDVW7sKmz4OneOEV07dKBrNz5rkyMPyrfI7Y3qQyBw_4Jsrau_fFojZYGpO3ijvYPnLgiH0ORV8G4qO8AUOtFQaQnCVfwveKa6CHBVyodKXTkRHX7IhCBAtoGS6fJZy9d-GjH8Tw_lrteJsWybBHlwZI4aLioEJ



How does it sound?

I conducted a comparison between the Onkyo RZ50 in pure output mode (RCA) and the BT30D Pro (RCA), both using RP5000F towers and an amp selector switch. I was unable to hear any difference between them, which is good news. It appears that the well-implemented TPA3255 chip sounds the same in all cases.

Same 32V-5A adapter used for multiple models.
7-qCKnEVzgXcBhEIefNtKbxnfm6ATCX8Iw8lnPADuLtqCDCml-llMCm2JklJA6T9aNZeCM5NPWuDJdjlU-qIh0jYNScWNUVEIbgcZUxFWl91H9rYkuWa5cMDkVU_l7Qq4BiZBQtZXrCbpDGazXPOnyIfYBNAHS-3Tr65pqEqpXsVDWRHgPcm1kBSo3CX


Everytime I plugged in the male power plug, there were sparks. I can see and hear it.


The power measurement:

Setup:
RCA Input signal @ 1000hz, 1Vrms
Tone control at half way

L & R both driven, 8 ohm load, 50W rms per channel, before clipping. Volume knob at 2.5 o’clock
1R3S1NbT0VNY8ApIgHuSMrxjVMruc_sek5hFlWNdM3btWrHPo7J7fp7Uz-LlrT8x8rz-zNC3a5eX1mbaZyG-IZgQPzlfztMOo69Z783BBGtkyPUbX_x3ygjit86A9dwK5LZQoL1mrRGru1KxcPK1dx0aKLa8eg8KbE5IqQgNK9cobzlXDfPl4dUsif02


L & R both driven, 8 ohm load, 60W rms per channel, clipping, Volume knob at 3 o'clock
o8_bO-NbwEYh51o9YpNYJp0Nbv8_VcuY3JnpMz1tIGrekTV_zyMOS1gDROCJElNbjd05XMAe8Zfq3qhhC2Tnqd_3fqU7yH4zhy8VRD3FUzCaDPrZD6F2bx_BZ3JcIl8tYOzcHDo3jGdE8f83TpCoGczCeWrVb8yX2x4NLX0ZdKo_3TIf5gobyJHwUVbH


L & R both driven, 4 ohm load, 85W rms per channel, before clipping. Volume knob at 2.5 o’clock
U2rAoMJdJoMpgW4fNfHl5hJUhtDuDCXq6SgUZvPCnj6Ibyql_xmK4r1m8Wj6SGBhkqOrQT09vcWWfPDOQP46kn1gqsyGS3YI9ge9EgrW3zmqADzamZN3bks03mxDXTEkxXs6wILXFEO1xtIGwAcV6z6X9Gw_wTapU3TwTpZTOzWkBNZAZWDvhSpt0G3I


I wasn't able to reach clipping at 4 ohm load. Either the amp or power adapter goes into OCP protect mode everytime.


Noise was tested at maximum volume. There was a barely audible hiss from the speakers, which could only be heard if you put your ear close to the tweeter. There is no circuit to shut off the signal because it is not audible when sitting away from the speakers.

0jBb6z-qLyKvm4HK4hF0h3VEoYaTfwrqS6Z88oMmMqO-YXxj-ghJlad3UHEbm_quKadufNlCEETV48S2oX_ku5Q36sQe2XCA3DZGKAqFKAHdIVMvh2pm2HLBP5iUZYvdpKBU67UVOZQIXXf5rAYwqvHjXNJaTXkXs1f9W3nVazGJcqRp0CQ7k03NGwRL


The TPA3255 chips are efficient and can produce a significant amount of power for their size.. You can increase the power output of these chips by upgrading upto 48V power adapter. However, because on the heat issue, I wouldn't do it unless you modify the enclosure with active cooling.

It appears that many manufacturers using this chip have set their power limits based on the capabilities of the power adapter.


Pros:
  • Great build quality
  • Excellent sound quality, to my ear it’s on par with the RZ50 and BT30D Pro
  • Low noise floor
  • Excellent price / performance ratio

Cons:
  • Thermal management
  • Sparks
I get a spark when connecting my Mac Mini 2020 M1....just saying.
 

Joe Smith

Addicted to Fun and Learning
Joined
Jan 4, 2019
Messages
983
Likes
1,027
Yeah, I wish Aiyima would offer a truly improved version of the A07 with higher-quality caps, better heat separation via a larger case, improved Op-amps, integral power (like the SMSL AO100), subwoofer outputs and ventilation holes in the case. The competition is really high now with SMSL, Fosi, Aiyima, others are working the same space... But if Aiyima had all of the above, priced at about $160, it would do OK I think... Their recent offerings don't do much for me...
 

Birdy

Member
Joined
Jan 11, 2022
Messages
70
Likes
31
Location
Brazil
Yeah, I wish Aiyima would offer a truly improved version of the A07 with higher-quality caps, better heat separation via a larger case, improved Op-amps, integral power (like the SMSL AO100), subwoofer outputs and ventilation holes in the case. The competition is really high now with SMSL, Fosi, Aiyima, others are working the same space... But if Aiyima had all of the above, priced at about $160, it would do OK I think... Their recent offerings don't do much for me...
Agree, but this would narrow their market quit a lot. I have no idea how far you could go to improve the A07 with real world SQ improvement for a reasonable price?
 

antcollinet

Master Contributor
Joined
Sep 4, 2021
Messages
7,408
Likes
12,291
Location
UK/Cheshire
What has happened to all your links? (I assume they were meant to be links - they just look like random text to me now. Perhaps they were images? Either way they are not working now)
 
OP
Pixelwarfare

Pixelwarfare

Member
Joined
Oct 3, 2022
Messages
16
Likes
40
The links of picture are broken, and I have no way to edit the original post...
 

Schlippwhip68

Addicted to Fun and Learning
Joined
Nov 28, 2020
Messages
511
Likes
198
Location
Essex, UK.
Yeah, I wish Aiyima would offer a truly improved version of the A07 with higher-quality caps, better heat separation via a larger case, improved Op-amps, integral power (like the SMSL AO100), subwoofer outputs and ventilation holes in the case. The competition is really high now with SMSL, Fosi, Aiyima, others are working the same space... But if Aiyima had all of the above, priced at about $160, it would do OK I think... Their recent offerings don't do much for me...
I agree Joe. At least certainly expand the case allowing vents and upgrade the caps. Then BRZHIFI have done something you might be interested in, the BRZHIFI 3255XLR. In my opinion and in many others for that matter it has a more muscular sound than the A07 (I have both) and it runs a lot cooler. It also has Neutrik balanced outs. You can check it out on Ali Express.
 
Top Bottom