Yes you can.
You would have to have a separate EMM server. Normally, the master server is the EMM server (holds the database), If you have a physically separate EMM server, this can support multiple master servers.
The only advantage I see to this, is perhaps better performance, but you are adding another layer of complexity to the environment which will possibly lead to longer troubleshooting times if there is an issue.
It is very rare to see this, I believe Symantec have only seen this a very few times. If it gave any great advantage, it would be more common,
My personal view, and one I know is shared by serveral backline engineers, is that multiple separate environments are better, certainly, I have seen very very high, consistant backup success rates using this approach. Eg, instead of one master/emm and 9 media servers, split this to 2 masters with 4 media servers each, I know of one customer who reported 100% success rate in a 24 hour period, they may have had failures, but had the ability to rerun - and this was on a reasonably large number of clients.
It comes down to cost, in a previous life my old firm had multiple masters (30 - 40) with mutiple medias on each, but, none of them were backing up 24/7, there was serveral hours a day in which maintainance could be done, or, perhaps more importantly, if we had an issue, we had the ability to fix the issue and then catch up on any important backups. If we really were in trouble with one, the other servers could be used to tempoarily carry out the backups for the clients of the broken server. We consistantly ran a success rate of about 98.5%, of 2500 servers and 70-80 TB backed up a day.
Consider the oposite, and I see this a lot - server usually backs up 20+ hours a day (or duplications etc ...) there is some issue and things fail. Straight away, what is perhaps technically a minor issue, is major problem beacuse as soon as you are a few backups 'behind' it is impossible to catch them up, as the new backups need to run.
My approach may have a slightly higher cost, but it is lot less stressful to maintain.
Martin