I’m looking to get a a QA403 to test my collection of amplifiers ( and maybe for more as a test rig for local enthusiasts going forward ) - I have a question about options for loading the amps - obvious choice is the load offered by QA but are there other more cost friendly options for the one off test case - like my 250Q speakers ?
It seems I can get dummy loads from digikey as an alternative but not too familiar how they’d look ( resistive / complex ? ) and if it’s a more realistic test to pair with speakers vs a dummy load
Testing with your speakers would get pretty loud and you may damage them in the process. I would do a search in these forums as several loads (resistive) have been presented, and of course there is the QA451 load. If you can’t find the load solutions in these forums I can post what I did.
Hi @Forwatt, the QA451 (which is in stock again) is made for fast testing and while it can do 200W for short periods, it’s not the tool you want for looking at high-powered amps in detail. Take a look at the link below. It walks through the different amp topologies and shows the build for a load that can cope with power levels up to to 1.7 kw.
All the design files are there too (gerbers, DXFs for aluminum laser cutting, schematics). See the bottom of the page.