Custom Shop @ Rosen Sound

The finest keyboard custom shop in Los Angeles


We have made the difficult decision to nix cosmetic customs for the next few years or indefinitely.
The amount of time, space, and money required for these total strip downs, matching of factory paints that have a short shelf life, matching of factory fonts and spacing etc etc is much too high in respects to the restoration workload we already have. There is simply not enough meat on the proverbial bone to justify these types of jobs where after all the hoopla usually results in a net loss of money for us and an excessive loss of time.
We want to be clear: We are specifically talking about the “dream looks” some people “dream” of and don’t have the budget for once all is said and done.
We are still refacing certain instruments but will not be adding to the repertoire anytime soon.

Here are some panels we can have redone for you, though, if you provide us the panel only:

ARP 2600 (vintage)
Oberheim OB-8
Oberheim OB-X
Oberheim SEM

Prophet 5 (vintage)

We have new panel overlays coming out soon for the Oberheim Matrix-12 & Xpander made of aluminum
We have new SEM panels coming soon
We are still working on a “group buy” of Jupiter-8 refinishing 

Electronic Customs

With cosmetic customs out of the way, we are still excited about your electronic customs/modification ideas. 

The most common modification we are asked to do is install MIDI in synthesizers. We are of course happy to install kits that we make as well as from other manufactures. 

MIDI retrofit manufactures we recommend:
– Our first choice in midi kits, especially for OB-X, Xa, Jupiter-8, Moog Source, etc come from Encore Electronics:
– We recommend all firmware updates that expand midi capabilities from Tauntek because they are not intrusive to the original workflow. Their firmwares are compatible with our own factory clone kits (OB-8, Prophet 5):
– For Juno-60, SH-101, Polysix, Mono/Poly we recommend kits from Tubbutec:
– We like CHD kits a lot too. Dead simple and usually not intrusive:
– We will install Kenton kits on request, but usually only for the CS-80 and Prophet-5 Rev 2:

Custom Modifications

Want to modularize your mono or poly synth or add oscillator sync and other features omitted from the original design? We can do all of these types of jobs to the highest standards, including custom PCB manufacturing and new panel manufacturing for a factory-like look. Please only note that these jobs can take a considerable amount of time and funds to accomplish. 

Wood Work & Tolex


We work with an awesome local woodworker doing synth wood work exclusively for our shop. We have had many wood cases made to the exact specification of the originals in original type and more luxurious hardwoods. We carry many wood sides for vintage synthesizers and can have almost any made. Our wood worker makes our most common sides by CNC and otherwise by hand. Wood projects, like other customs, can still take a considerable amount of time and expense,
but can result in a beautiful instrument!

At this time, please do not send wood side requests that aren’t for vintage synths. We are not going to be making MPC sides anytime soon

We stock sides for:
Oberheim OB-X
Oberheim OB-Xa
Oberheim OB-8
Roland Juno-106
Sequential Circuits Pro-One
Korg Mini-Korg

Tolex Work

Regarding tolex and the art of re-tolexing… we are happy to do the occasional tolex job but generally would rather reserve the misfortune of doing this type of work for when we must retolex a synthesizer we are selling. If your cabinet is in very bad shape, we will consider a re-tolex, but overall we will try to talk you out of it unless your tolex is torn to bits. The other challenge to consider when thinking about a tolex job is the original hardware is unlikely to be reused, so you must settle for different hardware in many cases. 

Customs Gallery

ARP 2600 & an Oberheim FVS-1 Both in brand new wood cabinets with new tolex and hardware for one customer.

Full stage rig for funk band Chromeo. All synths were stripped, chrome’d and new graphics applied. A huge and expensive process!

Korg PS-3100 housed in a brand new American Walnut case, made in house.

The “Moogerheim” we built for Synthplex 2019. Replica of Geddy Lee’s late 70’s synth rig. It worked, too!

EMA Synthi AKS with many mods, including oscillator sync, filter slew selection, CV control of wave shaping, and more!

Roland Juno-106 in a custom blacked out finish. Pitch wheel illuminated in white, white 7 segment screen, and tastefully added LED’s that aren’t blinding. Sounds as good as it looks!