What Is Speaker Reconing?

Reconing is a loudspeaker repair process in which the damaged moving assembly of a speaker is removed and replaced with new components.

Depending on the design and repair kit, the replacement assembly may include:

• Cone
• Voice coil
• Spider
• Surround
• Dust cap
• Tinsel leads
• Adhesives

The purpose is to restore the mechanical and electrical operation of the original driver as closely as practical.

Why Do Speakers Need Reconing?

A loudspeaker may require reconing when one or more of its major moving components has been damaged beyond practical repair.

Common causes include:

• Burned voice coil
• Open voice coil
• Damaged cone
• Torn surround
• Damaged spider
• Damaged dust cap
• Severe mechanical deformation
• Excessive excursion
• Thermal damage
• Age-related deterioration

Reconing vs Speaker Repair

Not every damaged speaker needs a complete recone.

Some problems can be repaired individually.

A complete recone becomes appropriate when several moving components need to be replaced or when the damaged parts are normally supplied as a matched kit.

The Main Components of a Recone

A typical recone assembly consists of several interconnected parts.

                Dust cap
                   │
                   ▼
             ┌─────────┐
           /             \
          /     Cone      \
         /                 \
        │                   │
        │   Voice coil     │
        │       │          │
        │      Spider      │
         \                 /
          \_______________/
              Surround
                  │
               Basket
                  │
                Magnet

All of these parts must work together mechanically and electrically.

Before Starting a Recone

Before removing anything, inspect the speaker carefully.

Determine:

• Speaker diameter
• Nominal impedance
• Voice-coil size
• Voice-coil configuration
• Magnet and basket condition
• Spider condition
• Surround condition
• Cone condition
• Terminal condition

The magnetic motor and basket should be in good condition before a recone is attempted.

Check the Magnetic Gap First

A recone cannot compensate for a badly damaged magnetic motor.

Inspect the pole piece, top plate and magnetic gap for:

• Foreign particles
• Rust
• Physical damage
• Magnet displacement
• Signs of voice-coil rubbing

The gap must be clean and mechanically stable before the new voice coil is installed.

Check the Basket

The basket must be structurally sound.

Check for:

• Cracks
• Bent frame sections
• Damaged mounting holes
• Loose motor assembly
• Damaged spider landing
• Corrosion

A badly bent basket can make accurate voice-coil alignment impossible.

Choosing a Recone Kit

The replacement parts should be appropriate for the specific speaker.

Important specifications include:

• Speaker diameter
• Nominal impedance
• Voice-coil diameter
• Voice-coil winding
• Former dimensions
• Cone dimensions
• Spider dimensions
• Surround dimensions
• Overall moving-assembly geometry

Using parts that merely look similar can produce a driver with different mechanical and acoustic characteristics.

Matching the Voice Coil

The voice coil is one of the most critical parts of a recone.

The replacement coil must be compatible with the magnetic gap and electrical requirements of the speaker.

Important characteristics include:

• Coil diameter
• Winding height
• Former material
• Wire size
• Impedance
• Winding configuration
• Thermal capability

Voice-Coil Impedance

The replacement voice coil should have the intended nominal impedance.

For example, an 8 Ω driver should not normally be converted into a 4 Ω driver simply because a replacement coil is available.

Changing the impedance changes the electrical loading presented to the amplifier.

Single Voice Coil vs Dual Voice Coil

Some speakers use a single voice coil while others use two separate voice coils.

Single voice coil:

Terminal ── Coil ── Terminal


Dual voice coil:

          ┌─ Coil 1 ─┐
Terminal ─┤          ├─ Terminal
          └─ Coil 2 ─┘

A dual-voice-coil recone must reproduce the correct coil configuration and connections.

Removing the Old Cone

The first major stage of reconing is removing the damaged moving assembly.

The cone, surround, spider and voice coil must be separated from the basket without damaging the magnetic motor or basket.

The removal method depends on the original adhesive and construction.

Removing the Dust Cap

The dust cap is often removed to gain access to the voice-coil area.

It should be removed carefully to avoid damaging the cone if the cap will be reused.

In a complete recone, the old dust cap is normally replaced.

Removing the Surround

The old surround must be separated from both the cone and basket.

Old adhesive should be removed carefully from the attachment surfaces.

The goal is to create clean surfaces for the new suspension components.

Removing the Spider

The spider is normally attached to the basket and voice-coil former.

It must be removed without damaging the basket or leaving excessive material that interferes with the new spider.

The spider landing area should be clean and smooth before installation.

Removing the Voice Coil

The damaged voice coil is removed together with the old moving assembly.

The magnetic gap should then be inspected carefully for debris or damage.

Even a small particle inside the gap can cause the new voice coil to rub.

Cleaning the Magnetic Gap

Gap cleaning is one of the most important steps in reconing.

The objective is to remove:

• Dust
• Old adhesive particles
• Metal particles
• Voice-coil debris
• Other contaminants

The cleaning method must avoid damaging the precision surfaces of the magnetic circuit.

Why the Magnetic Gap Must Be Clean

The clearance between the voice coil and magnetic structure can be very small.

A tiny particle can cause:

• Voice-coil rubbing
• Scraping noise
• Distortion
• Premature voice-coil damage

Installing the New Voice Coil

The new voice coil must be positioned accurately inside the magnetic gap.

This is one of the most critical stages of the entire recone process.

The coil must remain centered while the spider and other suspension components are attached.

Voice-Coil Alignment

The voice coil must have the correct position relative to the magnetic gap.

Correct:

      ┌─────────────┐
      │   │     │   │
      │   │ COIL│   │
      │   │     │   │
      └─────────────┘


Incorrect:

      ┌─────────────┐
      │ │           │
      │ │  COIL     │
      │   │         │
      └─────────────┘

Incorrect alignment can cause rubbing and distortion.

Voice-Coil Shims

During many recone procedures, temporary shims are used to center the voice coil in the magnetic gap.

The shims are inserted between the voice-coil former and the magnetic structure.

They hold the coil in the correct position while adhesives cure.

The exact shim dimensions depend on the voice-coil and magnetic-gap clearance.

Why Shims Are Important

Without reliable centering, the voice coil can move away from the centre of the magnetic gap during assembly.

Once the adhesive cures, this incorrect position can become permanent.

Accurate shimming therefore helps prevent voice-coil rubbing.

Installing the Spider

The spider connects the moving assembly to the basket while helping maintain voice-coil centering.

The spider must be positioned accurately and attached securely.

Its inner and outer attachment surfaces must be compatible with the replacement components.

Installing the Cone

The replacement cone is positioned over the voice coil and spider.

The cone must be aligned with the basket and suspension.

Its geometry must match the intended surround and voice-coil configuration.

Installing the Surround

The surround connects the outer edge of the cone to the basket.

It must be positioned without creating unwanted tension or misalignment.

The surround and spider must work together to keep the moving assembly centered.

Spider and Surround Alignment

The spider and surround must be installed so that the cone remains centered relative to the basket and magnetic motor.

An uneven or incorrectly positioned suspension can produce:

• Voice-coil rubbing
• Uneven excursion
• Mechanical noise
• Changed suspension characteristics

Installing the Tinsel Leads

The tinsel leads connect the voice coil to the speaker terminals.

They should be routed so that they can flex freely with the moving assembly.

They must not be too short, too stiff or positioned where they can strike the basket.

Tinsel Lead Attachment

The electrical connection between the voice coil and tinsel lead must be secure.

The connection also needs to withstand continuous mechanical movement.

A poor joint can cause intermittent operation or complete electrical failure.

Installing the Dust Cap

Once the moving assembly is correctly installed and the adhesives have cured as required, the dust cap can be attached.

The cap should be centered over the voice-coil area.

Its size and material should be appropriate for the driver.

Choosing Recone Adhesives

Different joints in a loudspeaker may require different adhesive properties.

The adhesive must be compatible with the materials being joined and with the mechanical stresses involved.

Important considerations include:

• Bond strength
• Flexibility
• Temperature resistance
• Vibration resistance
• Cure time
• Compatibility with cone and suspension materials

Do Not Use Excessive Adhesive

Using too much adhesive can add unnecessary moving mass.

It can also create stiff areas on the cone or suspension.

The objective is to create a strong and reliable joint with the minimum practical amount of adhesive.

Adhesive Curing

The adhesive must be allowed to cure according to its manufacturer's requirements.

Moving or testing the speaker too aggressively before the adhesive has fully developed its required strength can damage the repair.

Curing time varies considerably depending on the adhesive and environment.

Checking Cone Movement

After the repair has cured sufficiently, the cone should be checked for smooth movement.

With the speaker disconnected from the amplifier, gently move the cone using even pressure.

Listen for:

• Scraping
• Rubbing
• Clicking
• Buzzing
• Uneven movement

Any significant rubbing should be investigated before applying power.

Checking the Voice Coil Electrically

Use a multimeter to measure the resistance across the speaker terminals.

The reading should be consistent with the expected DC resistance of the voice coil.

An open circuit indicates a problem with the voice coil, tinsel leads or connections.

An unusually low resistance can indicate an electrical fault.

Initial Low-Power Test

A newly reconed speaker should initially be tested at low power.

This allows the repairer to listen for:

• Voice-coil rubbing
• Buzzing
• Loose components
• Abnormal distortion
• Tinsel-lead noise

Only after the speaker has passed low-level testing should it be considered for higher-power operation.

Break-In After Reconing

A newly reconed speaker may have suspension characteristics that change during its initial period of operation.

The spider and surround can become more compliant as the driver is used.

The exact amount of change depends on the materials and construction.

A cautious initial operating period can allow the suspension to settle before demanding maximum excursion.

Reconing and Thiele-Small Parameters

A recone can change the mechanical and electrical characteristics of a speaker.

Important parameters can include:

• Fs
• Qms
• Qes
• Qts
• Vas
• Mms
• Cms
• Re
• BL

If the replacement parts differ significantly from the original components, the resulting driver may no longer have exactly the same Thiele-Small parameters.

Why a Recone May Sound Different

A reconed speaker can sound different from the original if the replacement components have different characteristics.

Differences can result from:

• Cone mass
• Voice-coil mass
• Spider compliance
• Surround compliance
• Cone stiffness
• Damping
• Dust-cap mass

This is why using a proper matched recone kit is generally preferable to selecting unrelated components.

Reconing a Professional Woofer

Professional woofers can be good candidates for reconing because the magnetic motor and basket may remain usable even when the moving assembly is damaged.

The replacement kit should match the driver's intended design.

Particular attention should be given to voice-coil diameter, winding height, spider geometry and cone dimensions.

Reconing a Subwoofer

Subwoofer reconing requires particular attention to excursion and mechanical clearance.

The replacement spider and surround must allow the intended excursion without excessive restriction.

The tinsel leads must also tolerate the required movement.

Reconing a Tweeter

Tweeter repair is different from reconing a large woofer.

Many tweeters use specialized diaphragms and voice-coil structures that are difficult to replace without the correct repair parts.

A manufacturer-specific diaphragm or replacement assembly is often the most practical solution.

Reconing a Midrange Driver

Midrange drivers can have specialized cones and suspension systems designed for their particular frequency range.

The replacement cone and voice coil should therefore match the original geometry and intended operating range.

Common Reconing Mistakes

• Using the wrong voice-coil impedance.
• Using the wrong voice-coil diameter.
• Failing to clean the magnetic gap.
• Incorrect voice-coil centering.
• Using an unsuitable spider.
• Installing the surround off-center.
• Using excessive adhesive.
• Using ordinary wire instead of proper tinsel leads.
• Testing at high power before the adhesive cures.
• Ignoring mechanical rubbing during initial testing.

Why Voice-Coil Centering Is the Most Critical Step

The magnetic gap is a precision mechanical structure.

The voice coil must remain centered within it during operation.

Even if every other component is installed correctly, poor voice-coil alignment can make the reconed speaker unusable.

For this reason, centering should receive particular attention during the entire assembly process.

Reconing Workflow

Inspect speaker
       │
       ▼
Check basket and magnet
       │
       ▼
Remove damaged assembly
       │
       ▼
Clean magnetic gap
       │
       ▼
Install voice coil
       │
       ▼
Center voice coil
       │
       ▼
Install spider
       │
       ▼
Install cone
       │
       ▼
Install surround
       │
       ▼
Connect tinsel leads
       │
       ▼
Install dust cap
       │
       ▼
Allow adhesives to cure
       │
       ▼
Check cone movement
       │
       ▼
Electrical test
       │
       ▼
Low-power test

When Reconing Is Not Practical

Reconing may not be worthwhile when the magnetic motor, basket or other major components are severely damaged.

A speaker with a shifted or damaged magnetic structure can be particularly difficult to restore accurately.

The cost and availability of replacement parts should also be considered.

Reconing vs Replacing the Speaker

Tools Used for Reconing

Typical reconing work may require:

• Small knives or trimming tools
• Scrapers
• Adhesive application tools
• Multimeter
• Voice-coil shims
• Cleaning materials
• Clamps or suitable positioning tools
• Fine brushes
• Replacement recone kit

The exact tool selection depends on the speaker design and repair method.

A Clean Work Area Is Important

Reconing should be performed in a clean environment.

Dust and metal particles are particularly dangerous because they can enter the magnetic gap.

A clean work surface and careful handling can significantly reduce the risk of contamination.

Protecting the Magnetic Gap

During reconing, the magnetic gap should be protected from loose particles whenever possible.

Avoid working directly above an exposed gap with dusty materials.

Small pieces of adhesive, wire or metal debris can cause problems once the new voice coil is installed.

Reconing and Speaker Polarity

The new voice coil must be connected to the terminals with the correct polarity.

This is especially important when multiple speakers are installed in the same system.

Incorrect polarity can cause speakers to move in opposite directions, reducing acoustic output in some frequency ranges.

Reconing Quality Checklist

• Correct recone kit selected.
• Correct voice-coil impedance confirmed.
• Magnetic gap inspected and cleaned.
• Basket inspected.
• Voice coil accurately centered.
• Spider correctly positioned.
• Cone correctly aligned.
• Surround correctly attached.
• Tinsel leads correctly routed.
• Dust cap centered.
• Adhesives fully cured.
• DC resistance checked.
• Cone movement checked.
• Low-power audio test completed.

Key Takeaways

• Reconing replaces the damaged moving assembly of a loudspeaker.
• A recone can involve the cone, voice coil, spider, surround, dust cap and tinsel leads.
• The magnetic motor and basket must be in good condition before reconing.
• The magnetic gap must be clean before installing the new voice coil.
• Correct voice-coil alignment is one of the most critical parts of the process.
• Voice-coil shims are commonly used to maintain accurate centering during assembly.
• The spider and surround must be correctly positioned and securely attached.
• Tinsel leads must provide both electrical conductivity and mechanical flexibility.
• Excessive adhesive can add unwanted moving mass and stiffness.
• A reconed speaker may not have exactly the same Thiele-Small parameters if the replacement components differ from the originals.
• The repaired speaker should be checked mechanically and electrically before applying high power.
• Low-power testing should be performed before demanding full excursion or power.
• A proper matched recone kit is generally preferable to mixing unrelated components.
• Reconing can restore an expensive or professional loudspeaker when its magnetic motor and basket remain usable.