Looking for UPS suggestions

Looking for suggestions on double conversion (zero switch over time) UPS's. I'm looking for models that can be placed in studios, with minimal fan noise. Fan noise is OK when in operation, but not idling. I don't want to hear these things, if they are just sitting there trickle charging batteries. Looking for suggestions on mainly 1500 VA models (rack or tower), or series. Thanks.

We use APC and Eaton (are they still made?). Hot swappable, no fan noise, 2 RU. Uncertain of the double conversion, I just know our studios stay on.

We had tried STACO and switched them all out to less important areas when they all showed issues. We still use them, but they had some major issues on power outages that required full "power off" resets to get them back working, not great for critical applications.

I have not had good luck with APC's if they need to run off of a generator. When we lose power, a generator kicks in in about 20 seconds. The APC's really don't like this particular generator. YMMV. We have several Cyberpower rack mount UPS systems that are variable about running on a generator. Some like it, some do not, even though they all look cosmetically the same and have the same model number. Most recently we purchased a Trippe-Lite "Smart 1500" that seems quite happy on a generator. I don't believe it is dual conversion, but it has worked well through several power outages this spring. The equipment plugged into it has not lost a beat. I like that. This UPS is also pretty reasonably priced (about $165 from Amazon).

I've got a Tripp-Lite SMART3000 2U Rackmount (don't know about double conversion). Besides replacing the batteries over the years, it has worked perfectly. I'm running several servers in that rack, my EAS, and Audio Processors. It'll run for about 45 minutes which easily covers most of our power outages. Tripp-Lite also makes a 2U Extra Capacity Battery Pack that plugs right in to the SMART3000 (will double runtime). When active, I can't hear the fan but I can hear the inverter running (not annoyingly loud). I've also used some Belkin 800's in the past that worked well. For whatever reason, the batteries didn't seem to last over a year. However, they worked when I needed them.