Just wait a few minutes to see the Synths listed here.
The SynthDB offers a lot of info about all kinds of synths from Modular to Analog ones, find newer so called virtual analog synthesisers along with old and new non-analogues under Digital .I was a bit lazy, so the Software section is a bit limited to those I had or those I know quite good, I really hope to find the time to add some SoftSynth
Beats can be done with classic Drum Machine kind of electronic drummers dedicated to beats or drumming only or to the newer way for beats and club stuff, that more or less are dedicated to live performance and melodies, some can samples, others are synths or both - but today we call those synthesizers Groovebox. Sort of dying species is the Sampler in fact it is just, what synthesizers today add more and more, so find synths that are able to play synths under digital.
The Synthesizer List