I need some techy help in order a preamp--resistor values.

1. I've used passives and a slew of actives for 40+ years. Each has a sound. Each interacts with cables and associated electronics. There is no free lunch.

SMD resistors have lower inductance and thus have a different sound than leaded parts. However, they require a PCB and a different switch and thus have a different sound.

Each passive topology has its proponents. Each has a different sonic characteristic dependent on the associated components and cables.

^^ +1!

OK I'm not a fan of passive controls- so often I've seen them reduce bass impact and dynamic quality while otherwise seeming to be 'neutral'.
But having been in the industry for over 4 decades I can tell you that expensive resistors are expensive :)  Not only that but the lower the overall value of the control, the less effect they have.

If I were you I would see about auditioning first. If you are really stuck on a passive control, the best we have heard (and it really pains me to say this) is the Lightspeed. Its fairly cheap too as these things go.

But if it were me I'd do an active line stage before I used a passive. One problem not mentioned so much (particularly by manufacturers of passive controls) is that they are more susceptible to the variability of the sound of the interconnect cables themselves. Put another way, the lower the output impedance of whatever is driving the cable, the less you will hear the cable itself. Passives hive higher output impedances and thus often force you to audition lots of cables to find one that sounds right in your system- and even then, the only reason that cable is working is that you didn't find or hear about the one that works better than that.