Big Joanie’s Sistah Punk EP was recorded almost two years ago now. The London band’s first release is gloriously lo-fi: you can hear fingers sliding over strings, drum beats are simple, vocals are delivered with blunt nonchalance. A solitary woman peers out from the front of the cassette case – beehived, beautiful and self-assured.

“We don’t really know who the woman on the front is,” says guitarist Steph Phillips via email. “Chardine [Taylor-Stone, drummer] found a book of photo-booth pictures from the 50s and 60s in America and this one stood out to her for our EP cover. She looks pretty confident and sure in herself; she seemed like a great visual definition for sistah punk.”

Sistah punk is an important term for Big Joanie. It’s their self-described genre and the name of their newly-formed record label. Mostly, it’s a reaction. Black, female, queer, the band formed within a music scene that has traditionally been calibrated for the tastes of angry white males.

The band’s first gig was in 2013 at the inaugural First Timers event — a weekend festival in which all bands perform their debut show. The festival was formulated to address the lack of diversity in the London DIY music scene by helping to break down barriers to entry. Bands can sign up for workshops in the lead up to the show, encouraging people who may never have picked up an instrument before.

“First Timers was really important for Big Joanie,” says Phillips, “I had a few songs lying around for years and kinda of had an idea to start a band. It was only when I saw a callout for First Timers that I plucked up the courage to ask around if anyone wanted to start a black punk band. First Timers gave us a reason to form and a target to aim for right from the start.”

Phillips’s Facebook post caught the attention of Taylor-Stone, who decided to pick up drumsticks for the first time, and Kiera Coward-Deyell joined on bass. They pooled their influences to meld a sound they describe as “The Ronettes filtered through 80s DIY and riot grrrl with a sprinkling of dashikis”.

Gear-wise, they keep things deliberately minimal. “I used to play a white Mexican Strat that I bought with my student loan,” says Phillips, “Now I just got a Squire aqua green Jaguar so I’m really loving playing that. I don’t like too many pedals so I just have a Boss blues distortion.”

Since they began, the band members have been outspoken about the state of the punk scene. Last year, they got some online attention for posting a fierce list of propositions to the music venues they play in (“To make your night inclusive you need to do more than book a black punk band. We will not solve all your problems on our own”).

Phillips says the band plays in a supportive scene, but there can still be a lack of understanding on racial issues. “No one’s ever walked up to us and told us they hate us, but we do only gig in a pretty small scene at the moment. There are still problems though. We’ve had to deal with cultural appropriation at gigs or people just generally not understanding race.”

But attitudes do seem to be shifting: “When I started playing in my first punk band about six or seven years ago, there were barely any people of colour in bands in the scene. Now there are good handful of people being creative and making noise about the punk scene’s lack of diversity.

“Outside of the small DIY scene though I think we’re still at that level where the idea of black women in a band is still weird to some people.”

Last week, the band announced a new 7 inch, to be released in May. The title track, ‘Crooked Room’, has been posted as a teaser. It’s notably cleaner than the songs of Sistah Punk, but has a kind of discordant malice; where the melodies of Sistah Punk were soothing, ‘Crooked Room’ unsettles.

The song was inspired by a quote from American writer and political scientist, Melissa Harris-Perry: “when they confront race and gender stereotypes, black women are standing in a crooked room, and we have to figure out which way is up”. The release will also include ‘Baby Rust’, sung by bassist Coward-Deyell, and a cover of TLC’s ‘No Scrubs’.

I ask if Phillips ever gets exhausted by the constant quizzing on racial and gender politics, but she says no. “Some people think that we’re limiting ourselves by talking about our identity, but a black woman knowing that we’re a black feminist punk band wouldn’t think too much more about it. A white guy on the other hand might see that as super radical as it’s far from his comfort zone or what he knows.”

Phillips offers a summation that is as matter-of-fact as her vocal delivery: “I think identity is a reality, so I personally am happy to discuss it. How a person wants to take that information all depends on who they are and their view on my identity.”

Crooked Room’ is out 20 May via Sistah Punk Records.