VIABLUE QTC XL Spikes
Pickup available at The Listening Room Storefront
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Third-generation owner
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Availability
Availability
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Family-Owned Authorized Dealer
Family-Owned Authorized Dealer
We're an authorized dealer for every brand listed on this site, so your warranty is valid and fully supported. We're a real brick-and-mortar shop in Chestertown, MD with shelves of actual inventory, not a drop-shipper. Family-owned and run for three generations, since 1978.
Delivery and Shipping
Delivery and Shipping
Free shipping for most items over $100! Local delivery up to 500 miles more with minimum qualifying purchase.
See our shipping policies for details. We will contact you after your order.
The VIABLUE™ QTC XL (Quarter Tone Calibration Extra Large) Spikes are the ultimate heavy-duty solution for reference-grade audio isolation. Designed specifically for massive floor-standing speakers and high-weight equipment, these extra-large spikes are scaled up in every dimension to handle extreme loads without compromising acoustic precision. By channeling vibrations through a single point of maximum pressure, the QTC XL Spikes eliminate resonance, delivering a soundstage with unparalleled depth, clarity, and bass control.
KEY FEATURES
- Extreme Load Capacity: Engineered to support up to 300 kg per 4-piece set, perfect for flagship speakers.
- Extra Large Dimensions: Features a massive 48mm diameter body and 35mm discs for maximum stability.
- Smart Height Adjustment: Integrated mechanism offers a 3mm range for precise leveling.
- Vibration Control: Concentrates weight onto a microscopic point to eliminate disruptive resonance.
- Surface Protection: Includes XL Ø 35mm discs with stainless steel inlays to protect floors.
- German Craftsmanship: Precision-machined metal bodies with a 27mm fine thread for wobble-free performance.
BUILT FOR GIANTS: XL STABILITY
The "XL" isn't just a label; it’s a re-engineering of the spike concept for the heaviest gear on the market. With a substantial body diameter of 48mm and a total weight of nearly 1.5kg per set, these spikes provide a rock-solid foundation that smaller spikes simply cannot match. The massive 27mm fine thread connecting the two body parts ensures that even under loads of hundreds of kilograms, there is zero mechanical play or instability.

INTELLIGENT LEVELING
Leveling heavy equipment usually involves awkward adjustments with thin threaded rods that reduce stability. The QTC XL solves this with its "Simply Smart" height adjustment system. You can fine-tune the height by up to 3mm directly at the spike body. Because the adjustment happens over a wide 27mm thread, the spike remains perfectly rigid at any height setting, ensuring your massive speakers are both perfectly level and acoustically grounded.

MASTERING PRESSURE
The QTC XL Spikes operate on the principle of extreme pressure concentration. By pooling the massive weight of your equipment onto a tiny, exchangeable stainless steel peak, vibrations are prevented from traveling into the floor. This "mechanical diode" effect clears up muddy frequencies and allows your speakers to perform exactly as designed, free from the coloration of room resonance.

The Listening Room Difference
We’re a third-generation family business with a brick-and-mortar showroom in Chestertown, Maryland, and a reputation built on trust, not hype. Whether you’re visiting in person or ordering online, we bring decades of experience, personalized service, and honest guidance to every interaction. We don’t just ship boxes. We help build systems, answer your questions like real humans, and make sure every detail of your setup is right, from the cables to the final connection. Our passion is helping you get the most out of your gear, with support that lasts well beyond the sale.
SPECIFICATIONS
| Specification | Value |
| Model | VIABLUE™ QTC XL Spikes |
| Material | Coated metal bodies / Stainless steel peaks |
| Max Load | 300 kg (per 4-piece set) |
| Height Adjustment | 3 mm range (Integrated) |
| Total Height | 67 mm – 70 mm |
| Max Diameter | 48 mm |
| Item Weight | 1440 g (per set) |
| Adjustment Thread | 27 mm Fine Thread |
| Included Accessories | 4 XL Spikes, 4 XL Discs (Ø 35 mm), M6 Adapters |
| Finish | Available in Black or Silver |
| Origin | Made in Germany |

