- +Truly complete kit — horns, waterproof compressor, steel tank, switch, plumbing, and wiring all included
- +Loud, full triple-trumpet locomotive chord rather than a thin single note
- +Well-documented specs (dimensions, weights, duty cycle, PSI, part numbers) for clean planning
- +Waterproof, oil-less, sealed compressor suited to under-vehicle mounting
- +Established US brand with wide retailer availability and easy replacement parts
- −Decibel rating published without a test distance
- −Trumpets are chrome-plated ABS plastic, not brass or steel
- −Priced at the top of the mid-range (MSRP up to ~$620)
- −1-year defect warranty is short versus some competitors
- −1.5-gallon tank refills quickly under heavy honking
Methodology
This review aggregates publicly available information from manufacturer specifications, retailer listings, and verified user reviews. We do not perform hands-on testing. Last reviewed May 29, 2026. Our spec figures come primarily from Kleinn’s official Model HK6 product page, cross-checked against Summit Racing and other established retailers. Where Kleinn discloses a number we use theirs; where it doesn’t, we say so rather than guess.
Quick verdict
The Kleinn HK6 “Pro Blaster” is a complete, ready-to-install triple train horn system that pairs three chrome ABS trumpets with a waterproof compressor and a 1.5-gallon steel tank. It earns a 4.2/5 from us: the kit is well-documented, genuinely loud, and backed by a real US brand with strong parts support — but it’s priced toward the top of the mid-range, the trumpets are ABS rather than metal, and Kleinn quotes its decibel figure without a test distance. For a truck or SUV owner who wants a no-shopping-list, brand-name kit with everything in one box, it’s an easy recommendation.
What it is
The HK6 is a universal triple train horn kit — meaning it isn’t cut for one specific vehicle, but ships with a full onboard air system so it can be mounted on most trucks, SUVs, Jeeps, and larger vehicles with room under the bed or frame. The “triple” refers to three tuned trumpets of different lengths mounted on a single tri-mount block, which produce the layered, chord-like tone people associate with a real locomotive rather than a single flat blast.
Because the kit bundles the horns, compressor, tank, switch, wiring, and plumbing, it’s aimed at the buyer who wants one part number that covers the whole job instead of sourcing an air system separately. It’s a step up from Kleinn’s compact dual kits and sits just below the company’s steel-trumpet “Demon” series.
Specifications
| Spec | Value |
|---|---|
| Sound output | 151.8 dB @ 150 PSI (test distance not disclosed) |
| Trumpets | 3 (tri-mount block) |
| Trumpet lengths | 15.5” / 13.5” / 11.25” |
| Horn material | Chrome-plated high-impact ABS |
| Horn dimensions | 15.5”L × 11.5”W × 11.5”H |
| Compressor | Model 6275RC, 12V DC, oil-less, waterproof sealed |
| Compressor duty cycle | 50% @ 100 PSI |
| Compressor max amperage | ~20 A |
| Compressor weight | 9 lbs |
| Air tank | 1.5 gal all-steel, internal anti-corrosion coating |
| Max pressure | 150 PSI |
| Operating range | 140–160 PSI (pressure switch) |
| Solenoid | 12V chrome (P/N 307) |
| Warranty | 1-year limited (manufacturer defect) |
| Price | ~$465–$620 |
Kleinn does not publish chord frequencies (Hz) for the HK6, so we don’t list any — anything you see elsewhere is unverified.
What’s in the box
- Model 500 Sentinel tri-mount triple train horns with solenoid
- 6275RC waterproof, oil-less 12V air compressor (150 PSI)
- 6275RT 1.5-gallon all-steel air tank
- 2151 pressure switch (140–160 PSI)
- Horn button and wiring/installation harness
- 12 ft of 1/4” airline plus 12 ft of 3/8” intake airline
- Brass drain valve, safety blow-off valve, and high-pressure outlet fitting
- Thread sealant and mounting hardware
Pros
- Truly complete kit — horns, waterproof compressor, steel tank, switch, plumbing, and wiring all included, so there’s no second shopping trip.
- Loud and full-toned: three tuned trumpets give the layered locomotive chord rather than a thin single note.
- Well-documented specs (dimensions, weights, duty cycle, PSI, part numbers) make planning a clean install easier.
- Waterproof, oil-less, sealed compressor is a sensible choice for under-vehicle mounting and tolerates wet/dusty conditions.
- Established US brand with widespread retailer availability (Summit Racing, Offroad Alliance, others) and easy access to replacement parts.
Cons
- Decibel rating (151.8 dB) is published without a test distance, so it can’t be directly compared to brands that disclose theirs.
- Trumpets are chrome-plated ABS plastic, not brass or steel — fine for most users, but not the premium-durability tier.
- Priced at the top of the mid-range; MSRP runs to roughly $620, more than several comparable triple kits.
- 1-year defect warranty is on the short side versus competitors offering longer coverage.
- 1.5-gallon tank refills relatively quickly with repeated honks; heavy users may want a larger reserve.
Alternatives
- Kleinn HK9 — Kleinn’s step-up “Demon Steel” triple kit with steel trumpets and a beefier air package; worth it if you want metal horns and don’t mind paying more.
- Kleinn 230 — a more compact triple horn option from the same brand for tighter installs or buyers who already own an air source.
- HornBlasters Admiral 544K — a competing complete kit built around a 5-gallon tank, for buyers who prioritize air reserve and longer sustained blasts.
If raw output ranking is your main interest, our loudest train horns guide puts kits like this in context, and our decibels explained guide covers why test distance matters so much.
Install / compatibility notes
The HK6 is a self-contained 12V system: it needs a switched power source, a solid chassis ground, and a mounting spot for the compressor and the 1.5-gallon tank (15”L × 6”W × 8”H), typically under the bed, in a wheel well area, or along a frame rail. Because the compressor is waterproof and oil-less, under-vehicle mounting is acceptable, but Kleinn still recommends keeping the air intake away from direct water and road spray.
Wiring runs the compressor through the included pressure switch (cycling between roughly 140 and 160 PSI) and the horn through the 12V solenoid and dash button. Budget for an inline fuse and a relay appropriate to the compressor’s ~20A draw — standard practice for any air-system install. The tri-mount horn block measures 15.5” across, so confirm you have clearance before committing to a location. For a general walkthrough, see our how to install a train horn guide. Always check your state’s rules first — our legality pages cover where aftermarket horns are restricted.
FAQ
How loud is the Kleinn HK6 really?
Kleinn rates it at 151.8 dB at 150 PSI, but does not publish the test distance, so treat that as a marketing peak rather than a measured-at-X-feet figure. In practical terms it is extremely loud — comparable to other full-size triple train horn kits and far beyond any factory vehicle horn.
Is the HK6 a complete kit or do I need to buy an air system?
It’s complete. The HK6 includes the horns, a 12V waterproof compressor, a 1.5-gallon steel tank, the pressure switch, solenoid, airline, fittings, wiring, and hardware. You supply the vehicle, power, and mounting hardware location.
Are the HK6 trumpets metal or plastic?
They’re chrome-plated high-impact ABS plastic. That keeps weight and cost down and resists corrosion, but if you specifically want metal trumpets, Kleinn’s steel “Demon” series (such as the HK9) is the upgrade path.
Will the HK6 fit my truck or SUV?
It’s a universal kit designed for most trucks, SUVs, and Jeeps with room for the compressor and the 1.5-gallon tank. Always measure your intended mounting area against the published horn (15.5” wide) and tank (15” × 6” × 8”) dimensions before ordering.
What warranty does it come with?
Kleinn covers the kit with a 1-year limited warranty against manufacturer defects. Keep your receipt and register if the brand offers it, since warranty terms apply from date of purchase.
How does it compare to the Kleinn HK9?
The HK9 is the step-up model with steel trumpets and a larger air package, generally louder-sounding in tone quality and more durable, at a higher price. The HK6 is the value-oriented ABS choice that still delivers the genuine triple-horn chord.
Sources
- Kleinn — Model HK6 Triple Train Horn Kit (official product page) — dB rating, trumpet count and lengths, materials, compressor/tank specs, duty cycle, pressure range, solenoid, warranty, included items, price
- Kleinn — Model HK6 (NOB variant) — variant pricing and gallery photo
- Kleinn — Model HK6 (SOD variant) — variant pricing and gallery photo
- Summit Racing — Kleinn HK6 ProBlaster Triple Train Horn Kit — retailer specs and availability cross-check
- Offroad Alliance — Kleinn HK6 Pro Blaster Triple Air Horn Kit — compressor/tank confirmation, retail pricing cross-check
- Dales Super Store — Kleinn HK6 — third-party spec and price cross-check
Train Horn Hub aggregates publicly available data. We do not test products in-house. All trademarks belong to their respective owners.
A complete, well-documented, genuinely loud triple train horn kit from an established US brand — the right pick for a truck or SUV owner who wants everything in one box and doesn't mind paying mid-range-plus for ABS trumpets.