Seems about right. TDA1524 output noise floor is given as about 100 µV in the datasheet, while for LM1036 it's 10 µV at minimum volume, which actually is an acceptable value for a hi-fi preamp (it's about what you'd expect from a 4558/4560/4565 class opamp at +16.5 dB). It looks like the NatSemi part implements a 2-stage volume control, which permits getting along with the relatively modest 80-ish dB dynamic range afforded by its circuitry.
Neither of the two is explicitly intended for hi-fi applications, though if in doubt I'd infinitely prefer the (more recent) LM1036. You just need to watch out for its limited input level handling and output level.
BTW - if you want 100 µV of output noise or less with a 26 dB power amp of 1.5 V input sensitivity, preamp output noise needs to be 5 µV or less - the final stage needs to have an SNR of almost 110 dB (or actually more, since preamps can often output up to 6-7 Vrms or even more - that puts us at 124 dB+). In case of the LM1036 the last stage seems to be good for about 100 dB.
Neither of the two is explicitly intended for hi-fi applications, though if in doubt I'd infinitely prefer the (more recent) LM1036. You just need to watch out for its limited input level handling and output level.
BTW - if you want 100 µV of output noise or less with a 26 dB power amp of 1.5 V input sensitivity, preamp output noise needs to be 5 µV or less - the final stage needs to have an SNR of almost 110 dB (or actually more, since preamps can often output up to 6-7 Vrms or even more - that puts us at 124 dB+). In case of the LM1036 the last stage seems to be good for about 100 dB.
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