Last night I listen to a guy play slap upright Bass. His tone and his volume was spot-on perfect. He told me he was using a schatten pickup system. No preamp. He said with the head he was using he did not need a preamp. I think he was using a TC electronic bh500. My question is this. Are there only certain types of amps or amp heads that will produce a real good sound tone wise and volume wise without a preamp? But I tried using a pickup system without a preamp and felt my volume was way too low. Tell me what you think.