What an Amplifier Chassis Actually Costs to Manufacture
September 18, 2026
Most hi-fi brands get their first chassis quote and assume the shop is guessing. It is usually not. The quote is made of five or six lines, and once you can see them you can also see which ones you control.
The lines in a chassis quote
| Line | What it covers | Who controls it |
|---|---|---|
| Material | Billet plate, extruded profile or sheet, plus the offcut you pay for | You, on the drawing |
| Setup and programming | CAM, fixtures, first article, paid once per order | Quantity |
| Machining time | Spindle time per piece across all operations | Geometry |
| Finishing | Deburr, brush or blast, anodize or coat, rack time | Finish choice |
| Cosmetic inspection | Checking the visible faces, and the parts rejected doing it | Finish choice |
| Secondary work | Engraving, silk screen, inserts, hardware, individual packing | Your spec |
Nothing on that list is padding. The one that surprises people is cosmetic inspection, because it is invisible until a batch fails it.
Billet, extrusion or sheet
A 10 mm thick front panel milled from 6061 plate is the expensive option and usually the right one. You get square edges, a clean chamfer and an alloy that anodizes predictably.
An extruded 6063 sleeve or heatsink costs a fraction of that per length, because the profile does the shaping and the shop only cuts, faces and drills it. The trade is colour: 6063 anodizes brighter than 6061, so a billet faceplate bolted to an extruded sleeve will not match unless both are dyed dark enough to hide it.
Folded 5052 sheet is the cheapest way to get a cover or a back panel. It is not a good way to get a front panel, because the bend radius and the sheet surface both read as cheap next to a machined face.
Why 30 units hurts
Setup is paid once. On a run of 30 chassis with four machined parts each, you are paying four setups and four first articles across 30 pieces. The same order at 300 pieces spreads those same setups ten times further.
The finish line behaves the same way. An anodizing rack has a minimum load and a fixed cycle. A part is dyed for the same time whether the rack is full or a quarter full, and you pay for the rack.
This is why a shop that quotes you 30 pieces at close to the 300 piece price is either wrong or including something you did not ask for. It is also why telling the shop your yearly volume matters even when you are ordering 30 now.
What you can change on the drawing
Four things move a chassis quote without changing the product:
- Tolerance only what matters. Panel gaps and knob fits need numbers. The back face of a heatsink does not. Every general tolerance tighter than ±0.1 mm is machine time you are buying for nothing.
- Cut the number of cosmetic faces. If only the front face and the top chamfer are seen in use, say so on the drawing. The shop can then handle and inspect accordingly instead of treating all six faces as critical.
- Choose a forgiving finish. Bead blast and clear anodize hides more than a mirror polish or a flat black. A dark colour anodize on 6061 is the least forgiving combination in common use.
- Standardise your fasteners. Three thread sizes across a chassis means three tool changes and three inserts on the bench. One size is cheaper in machining, assembly and spares.
What not to cut
Do not remove the first article with the real finish. It costs a few hundred dollars and a week, and it is the only point where you find out that the black is browner than the sample before 60 pieces exist. Any shop that tries to skip it on a cosmetic part is quoting for a different job than the one you have.
Frequently asked questions
Why is my chassis quote so much higher than a generic CNC quote?
A generic quote prices machining. An audio chassis quote prices machining plus a controlled finish plus inspection of the visible faces plus the scrap rate that comes with both. On a brushed and anodized faceplate the finish side can be half the price.
Is billet always better than extrusion?
No. Billet gives you a thick front panel with crisp chamfers and one alloy through the whole part. Extrusion gives you a long heatsink or sleeve at a fraction of the material cost. Most chassis use both, and mixing them is fine as long as you accept that the anodize colour will not match exactly between 6061 and 6063.
At what quantity does cost per unit stop falling?
Usually somewhere between 200 and 500 pieces for a machined panel. Below that, setup and the finish rack dominate. Above that, cycle time and material do, and the curve flattens.
Need a quote for this part?
Send the drawing. We match you with up to 3 shops and reply within 24 business hours.
Get matched with an audio parts shopKeep reading
- Billet, Extrusion or Folded Sheet: Choosing How to Build a Chassis
- Specifying and Machining a Heatsink Extrusion for an Amplifier
- Getting a 19 Inch Rack Panel Right the First Time
This guide is part of Audio Chassis Manufacturing: The Whole Picture, one of four sections in the guide library.