When I took my first undergraduate EE class at Caltech in the late 70's they used this text. Key point here: Not written by anyone at Caltech (so maybe the profs that chose it weren't biased?). I remember it as being pretty good, it was used for several years back then. Good enough for me to refer back to many times. It has good treatments of transistor amplifier configurations which you will want for guitar amps. Maybe not so much about tubes since except for very high power at very high frequencies, and audiophiles, tubes aren't favored in real world designs anymore. The digital stuff is at a basic fundamental level, no FPGAs, PLDs, or modern uPs back then. That's OK IMO, the complexity in modern digital designs is at the system level, the rest is "cookie cutter" implementation or HDL programing languages. The input and output circuits in digital ICs are best understood as analog circuits, IMO.
I don't claim to know about others, however. The real reason I mentioned it is that you can buy a used copy for about $10. It is worth $10! Sometimes when you are learning it's good to see different treatments of a subject if your primary text is confusing on some subject.
Integrated Electronics: Analog and Digital Circuits and Systems, Millman & Halkias, McGraw Hill
From one of the Amazon reviews:
Integrated Electronics: Analog and Digital Circuits and Systems
McGraw-Hill Book Company, Inc., 1972, pp. 911
LCCN 79-172657
by Jacob Millman, Ph.D., Professor of Electrical Engineering, Columbia University
Christos C. Halkias, Ph.D., Professor of Electrical Engineering, Columbia University
Preface
1. Energy Bands in Solids
2. Transport Phenomena in Semiconductors
3. Junction-Diode Characteristics
4. Diode Circuits
5. Transistor Characteristics
6. Digital Circuits
7. Integrated Circuits: Fabrication and Characteristics
8. The Transistor at Low Frequencies
9. Transistor Biasing and Thermal Stabilization
10. Field-effect Transistors
11. The Transistor at High-Frequencies
12. Multistage amplifiers
13. Feedback Amplifiers
14. Stability and Oscillators
15. Operational Amplifiers
16. Integrated Circuits as Analog System Building Blocks
17. Integrated Circuits as Digital System Building Blocks
18. Power Circuits and Systems
19. Semiconductor-device Physics
Appendices
A. Probable Values of Physical Constants
B. Conversion Factors and Prefixes
C. Problems
Index