TIP - Effective USB powered FM signal amplifier

Had previously bought the following USB powered FM signal amplifier, as part of a antenna kit, to overcome the loss of access to the building FM antenna facility (REF: http://myoldvintagehifi.blogspot.com/2019/02/alternate-analogue-fm-reception-for.html)

I can definitely recommend this USB powered FM signal amplifier as it is works very well and is a cost effective solution. Even bought a 2nd unit for another tuner in the house!

It is basically the no-frills version of the FM signal amplifier which was originally intended for use in motor vehicles but altered to draw power via USB. Hence there is no need to buy the expensive radio signal amplifiers or antenna kit as the total cost for all the items in the pix(s) below cost less than the price for a single signal amplifier unit (only) at the local shops!

Note - May need to purchase connector adapter(s) to enable connectivity and an external antenna

For the 2nd installation I used a salvaged WIFI 5dB antenna, mounted on a external SMA-connector type WIFI antenna kit - see items below. Works great and the solution does not cost "an arm-and-leg"😁

Salvaged 5dB WIFI antenna on SMA mount

Bare SMA connector and mount kit fitted with adapter(s) for connecting to tuners 

Blue-tooth receiver with audio player and ESS DAC

Just received my new Trasam DAC2PRO earlier this week. 

Trasam DAC2PRO (silver) directly connected to the Sansui B-2101 amplifier

The DAC2PRO provides a blue-tooth upgrade to my existing hifi setup with RC and remote volume control.

In addition, the unit has the ability to playback FLAC, MP3, WAV, M4A encoded audio via a ESS based DAC. The on-board DAC processes input received via a soft selector for COAX, OPT and Blue-tooth😑.

I ordered a unit with audio quality components from the Chinese eBay equivalent - came with black colour Nichicon EC capacitors on the power circuits and a OracleII-02 op-amp on a DIP-8 mount (phew!). Rest of the components are SMD types.

Was quite disappointed there was no MUSES op-amp provided with the unit. Hence I ordered a MUSES-8820 and 8920 as these are quite affordable nowadays as these have been superseded by the newer (and more expensive) MUSES-01 and 02.

Will update with more pix(s) and feedback of the sonics with the Oracle vs the older MUSES op-amps once I have the opportunity to perform the review.

In the meantime, I will have a play with my new toy 1st....😀

Changing OP-Amp(s) on the DIY TDA1541A DAC (***Update***)

Since spending more time online nowadays (due to COVID resurgent worldwide), I chance upon some good deals for better OP-Amp(s) from overseas. This was a good opportunity to swap-out the default NE5534P on my DIY TDA1541A DAC with USB interface, as I have (more or less) done all I can with capacitor replacements - not in the blog but had swap out the output capacitors for Elna Stargates since the last post for the DIY DAC.

Have decided I was not going to spend silly amounts on buying blackcaps, silver cabling or anything fancy of that sort since I wanted to see how far I can improve the unit on a budget. So will not splash out on Burson op-amps, MUSES-03 or alike.

Thus have ordered some Philips NE5534P, JRC 5534 and  OPA604AP.

Will update once I received the goodies and can do some swap-outs tests.

21Jun2021

Received the above op-amps and did the swap tests.

Ti NE5534 The default which came with the kit. My personal take is that it was the "Jack of all trades" but "Master of None" with a skewed HF reproduction and bass which was not flabby nor tight.

JRC NE5534 The minimalist choice. Has better overall balance than the Ti but came with a "English"-like reserve. Again nothing really wrong but did not excel in any particular area(s).

Philips NE5534 Best way to describe this would be to say it's alike the "Toyota Corolla" of 5534(s). Prefer it over the previous version of 5534(s) but know I could get a better replacement.

BB OPA604AP Initially the HF sounded thin with non-existant LF. After a couple of days usage, the sound stage surfaced. After another few more days, the most astonishing thing happened - the DIY DAC now sounds pretty close (after the unit has warmed up) to my Meridian 602 when performing an A-B comparison, with a slight difference in the output volume during the A-B comparisons.

OPA604AP x 4 on the DIY DAC PCB

Yup, left the OPA604AP(s) in-place  ....😁