Super Xiao 2x125W Power_DAC+SMPS PCBA 139x100x29mm

iWoofer

And finally the new version of H-Fi TOY! Now even smaller 127x100mm but more expensive 4 layers PCB. What's new: TAS5624(closed loop power stage i.e. with noise-shaper inside) replaced by TAS5342(open loop power stage with custom noise shaper as additional small PCB). The goal is two modes digital amplifier with the switch Open/Closed. The open loop mode stands zero feedback and quite high THD+N(.1% at 50W) but some audiophiles would prefer it doe to pleasant sound. Closed loop mode uses additional small PCB 45x25mm with noise-shaper (loop filter with very fast Opamp) THD+N .005% @ 50W. Both modes could be switched online by iPhone/Android app.
最后是新版H-Fi TOY！ 现在更小的127x100mm但更贵的4层PCB。 新增功能：TAS5624（内置噪声整形器的闭环功率级）由TAS5342（带定制噪声整形器作为附加小型PCB的开环功率级）取代。 目标是开关打开/关闭的两种模式数字放大器。 开环模式代表零反馈，THD + N相当高（50W时为0.1％），但一些发烧友会喜欢它的悦耳声音。 闭环模式使用额外的小型PCB 45x25mm与噪声整形器（环路滤波器，运算速度非常快），THD + N .005％@ 50W。 这两种模式都可以通过iPhone / Android应用程序在线切换。

iWoofer

I thinking about the die-cast heatsink ;)

gjh123

楼主确实有专业做技术的，赞一个

iWoofer

xie xie, today I've reduced the noise a lot. Closed loop mode(i.e. noise-shaper On) S/N about -108db, open loop mode(noise-shaper Off) S/N -102db.

iWoofer

This file 24/96(R/R->600:600 transformers->OPA1612 buffers->CS5381 residual S/N=-119db-A) was recorded directly from HiFi-TOY MK-I(TAS5558+TAS5624) output with 8" speakers connected https://yadi.sk/d/BUbLixUb3YqTja
This one is original track for your reference, if anyone can hear the difference https://yadi.sk/d/jrH66Sq93YqUjC

iWoofer

HiFiTOY app GUI https://www.youtube.com/watch?v=AFyk3HVTcGU
Dynamically allocated biquads between 2/4ord filters and parametric EQs ;)

ss0009671

中文字幕看久了,英文快要看不懂了.

manyouzhe

verry good!  nice!

iWoofer

Xie xie, this one link is better for china https://yadi.sk/i/JV7fGamy3ZM8cv

litguy

iWoofer 发表于 2018-7-19 20:28
Xie xie, this one link is better for china https://yadi.sk/i/JV7fGamy3ZM8cv

有淘宝 ？

iWoofer

Not yet, I still not sure, should I produce that product and sell by myself or sell the design for a good royalty.

还没有，我仍然不确定，我应该生产该产品并自己出售或出售设计以获得优质版税。

电路板

Normally we are prefer solid state amplifier more than IC or digital one. So most os us are building with classical circuits, eg. OCL,OTL...But it's not aboalute, some of us dont refuse to try latest digital AMP. If you invested much on Ad., I think you'll have many customers on your net salesment. Good luck Bro.

iWoofer

I trying to explain to audio industry people that their business shrinks not because of smartphones but due to all smart and bright engineers left audio ;)

电路板

dont think digi amp have a better audio listening performance than tranaiator amp. although digi amp has better paramerters than transiators set, the listening experience may not satisfy the user. Ofcourse digi circuit has its advantage utilize, that is small signal processing. So we'll really appriaciate if you can develope a WAV/APE player independent of IOS/Android. Its just my advice, may not right.But we hope have a high performence digi player system just composed by chipsets.

iWoofer

the boring thing is the blind test, which never let people hear the difference. I tried A/B blind test with a lot of different people who believed they can hear UcD like class D vs class AB, it's always failed. Of course, if class AB was technically good enough, like Accuphase and so on. Vintage solid state amps 1975 year plays differently indeed, as well as tube SE sounds differently vs all others.

iWoofer

Which high resolution audio interface would you like to have, HDMI or USB? HDMI doesn't need install any driver, very cheap WiFi->HDMI dongles available with Airplay ability(actually also isn't highres audio but 16/44 losless at least). USB seems perfect but only for PC users, with installed driver 24/192 no problem, Mac users will have only 16/48.

iWoofer

I just tested the SPDIF/Toslink board on PCM9211, works fine, and fully auto accepts 16-24bit 44.1-192kHz. SPDIF_TX always sending TAS5558 input data whatever SPDIF_RX/ADC or USB input selected. So it allows using more than one HiFi-TOYs together for bi/tri-amping, i.e. in-serial USB/RX1->AMP1->TX1->RX2->AMP2 etc. Due to PCM9211 has an ADC onboard, not so cool one S/N -101db 24/96, I decided to use it just in case(not sure if someone needs it if already has USB/SPDIF-Toslink). Anytime when SPDIF_RX isn't detected, HiFi-TOY automatically play from analog inputs(both 3.5mm Jacks could be an analog input either SPDIF_RX or SPDIF_TX). I think it is crazy compact design again(39x24mm the same as BT_stream board which could be optionally installed instead of SPDIF board), as the whole HiFi-TOY actually ;)

我刚刚测试了PCM9211上的SPDIF / Toslink板，工作正常，完全自动接受16-24bit 44.1-192kHz。 无论选择何种SPDIF_RX / ADC或USB输入，SPDIF_TX始终发送TAS5558输入数据。 因此，它允许将多个HiFi-TOY一起用于双/放大，即串行USB / RX1-> AMP1-> TX1-> RX2-> AMP2等。由于PCM9211板载ADC，不太酷 一个S / N -101db 24/96，我决定使用它以防万一（不确定是否有人需要它，如果已经有USB / SPDIF-Toslink）。 无论何时未检测到SPDIF_RX，HiFi-TOY都会自动从模拟输入播放（两个3.5mm插孔都可以是模拟输入SPDIF_RX或SPDIF_TX）。 我认为它再次是疯狂的紧凑设计（39x24mm与BT_stream板相同，可以选择安装而不是SPDIF板），因为整个HiFi-TOY实际上

iWoofer