DRV134PA 单端转平衡有兄弟玩过没？

ttcq

因为测试用的声卡是平衡输入的，接成单端输入指标大幅下降，想加一级转换。DRV134PA 单端转平衡有兄弟玩过没，还有平衡转单端的ina137.

gxvhxv

并不会大幅下降，只会影响增益。说句实话，diy不过关的话，加个香炉比冷端直接接地参数会差很多，那才是大幅下降

ttcq

gxvhxv 发表于 2026-8-28 17:44
并不会大幅下降，只会影响增益。说句实话，diy不过关的话，加个香炉比冷端直接接地参数会差很多，那才是大 ...

看到ASR上有个贴，
E2x2 输入不平衡——性能不佳
Thread startercelstark  Start dateNov 22, 2025
celstark
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Joined  加入Feb 17, 2025  2025 年 2 月 17 日
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Nov 22, 2025
#1
I'm looking to use a new Topping E2x2 as a measurement rig as its ADC is quite solid. When I do a loopback test on the unit itself, going from its balanced TRS line output to its balanced TRS line input, I can get nice, expected results. THD is down -104 dB or so in quick testing in REW and MultiTone and life is good (yes, odds are its DAC is holding this back and yes, I know to make sure the phantom power is off before connecting).
我打算使用新的 Topping E2x2 作为测量设备，因为它的 ADC 性能相当出色。当我对该设备本身进行回环测试时，从它的平衡 TRS 线路输出到平衡 TRS 线路输入，我得到了令人满意的结果。总噪声比下降了-104 分贝左右，在 REW 和多声道测试中效果很好。不过，我知道在连接设备之前，必须确保电源已关闭。

When I try to use an external, unbalanced DAC as the source, however, things fall apart. I've got a cable setup to go from the RCA's hot to the TRS tip and its gnd to go to either both the ring and sleeve or just the ring (doing a ground lift). No matter what, THD shoots up to -85 dB or so with lots of 2nd harmonic. I've tried two different DACs so far, so I doubt it's a faulty DAC. Cables are all just a few feet on the desk.
当我尝试使用外部的非平衡式 DAC 作为源时，情况却变得很糟糕。我使用了一种电缆连接方案，将 RCA 接口的正极连接到 TRS 接口的尖端，而地线则连接到环和套管之间，或者仅仅只连接到环上（采用接地方式）。不过，无论采用哪种连接方式，总谐波失真都会上升到-85 分贝左右，而且会产生大量的二次谐波失真。我已经尝试了两种不同的 DAC，所以我认为问题并不在于 DAC 本身有故障。这些电缆都放在桌面上几英尺远的地方而已。

What am I missing here? I'd have thought one of those two wiring setups would work.
我到底忽略了什么？我原以为这两种接线方式中的其中一种应该是可行的吧。