Dear Talkbassers, after listening .... and recording... and analyzing the way my new electric bass (4 months) sounds, i got the conclusion that the onboard Glockenklang 3-bands preamp rolls of the high frequencies when the volume pot is not full maxed. Even if i take it back just a bit, i hear a difference. And i mean in active mode. It's not something like "fletcher-munson curve", etc...... I analyzed several time the spectrum of recordings i made with 100% volume and then with not 100% volume, at 24bit @ 96 Khz. The long story is that months ago i had several units sent back to the Glockenklang factory because these units suffered from electromagnetical interferences and the volume pots where not precise. This last unit they sent me had a different push-pull volume pot, and they told it was an upgrade, besides the upgrade in an integrated circuit which picked up every sort of interference nearby (before). So, i've already had my dose of communicating with these folks... and honestly i'm fed up with this...... The fact is: i rarely max out the volume in my basses. I'm used to older Bartolini preamps (especially the TBIBT, which i cannot find anywhere for this new bass, else i'd bought it in a second), and these don't rolloff highs, anywhere, even at 5% of volume. I use, for the 90% of time, the volume at 3/4 of its course, because i need adjustment. With the Glockenklang i cannot do it anymore, because it sounds different. I don't care if old Glock units sounded different: now they do it this way. And i don't like it. And i didn't find anywhere in the web were it was said, otherwise i'd have never bought it. So, my question is: are you aware if other current onboard preamps in the market now suffer from the same rolloff? In particular, i'm interested in the Aguilar OBP3. Does it rolloff highs? ..... And i absolutely don't care to have a passive mode. But i don't want to drill or fill the holes in the bass. I want something with 5 pots, and with a good hi-fi sound. Another question: as the Glockenklang preamp has a 1:1 ratio regarding active/passive output level, and i really would benefit from a boost in volume in active mode (i never go passive), in your experience has the OBP-3 a sufficiently hotter output, more than if we were going in passive with the PUs ? Thank you for your eventual replies. And thank you once more if someone has a TBIBT unit he wants to sell .... Greetings.