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<title>Build a Stereo LM386 Audio Amplifier</title>
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<header><div class="shell hero"><div><div class="eyebrow">Workbench guide · beginner friendly</div><h1>Build a <span>stereo</span><br>audio amplifier</h1><p>A practical, breadboardable two-channel speaker amp made from a pair of classic LM386 low-voltage power amplifier ICs. Follow the signal from a stereo source through independent volume controls to two small speakers.</p><div class="hero-tags"><span class="tag">2 × LM386N-1</span><span class="tag">9 V DC</span><span class="tag">8 Ω speakers</span><span class="tag">No soldering required</span></div></div><div class="hero-mark" aria-hidden="true"><svg viewBox="0 0 130 130"><path d="M13 65h24m0 0 20-22v44L37 65m20 0h18" fill="none" stroke="#51d9e8" stroke-width="4" stroke-linecap="round" stroke-linejoin="round"/><path d="M75 39v52l35-26z" fill="#183544" stroke="#67aaff" stroke-width="3"/><path d="M80 54h-5m5 22h-5m35-11h11" stroke="#edf5fa" stroke-width="3"/><circle cx="65" cy="65" r="60" fill="none" stroke="#284454" stroke-dasharray="2 7"/></svg></div></div></header>
<div class="shell layout"><nav aria-label="Guide contents"><strong>On this page</strong><a href="#overview">How it works</a><a href="#safety">Safety & tools</a><a href="#parts">Parts list</a><a href="#schematic">Schematic</a><a href="#breadboard">Breadboard map</a><a href="#assembly">Assembly</a><a href="#testing">Test & troubleshoot</a></nav>
<main>
<section id="overview"><div class="section-head"><span class="num">01</span><h2>What you’re building</h2></div><div class="card"><p>The LM386 is a small monaural power-amplifier IC: it raises a low-level audio signal enough to drive a modest loudspeaker. Stereo is two independent mono amplifiers—one for left, one for right—with a shared supply and ground. Each channel’s output is AC-coupled to its speaker by an electrolytic capacitor, keeping the chip’s DC bias off the speaker.</p><div class="grid2"><div class="mini"><h3><span class="icon">↗</span>Signal path</h3><p>3.5 mm stereo input → separate 10 kΩ volume pots → coupling capacitors → LM386 inputs → output capacitors → 8 Ω speakers.</p></div><div class="mini"><h3><span class="icon">⌁</span>Expected result</h3><p>A simple, useful desktop / experimenter amp for small speakers. Output is modest and depends on supply, speaker, and signal; it is not a high-power or hi-fi amplifier.</p></div></div><div class="callout"><strong>Design choice:</strong> The gain pins (1 and 8) are left open, giving the LM386 its default voltage gain of about 20. This keeps the build less hiss-prone and more stable than the optional gain-200 configuration.</div></div></section>
<section id="safety"><div class="section-head"><span class="num">02</span><h2>Safety & prerequisites</h2></div><div class="card"><div class="callout warning"><strong>Power safely.</strong> Use only a current-limited low-voltage DC supply or a fresh 9 V battery for this build. Never connect a breadboard circuit to mains voltage. Disconnect power before changing wiring; electrolytic capacitors are polarized.</div><div class="grid2"><div class="mini"><h3><span class="icon">⌕</span>Workbench & tools</h3><ul class="clean"><li>Solderless breadboard and insulated jumper wires</li><li>Digital multimeter (voltage, resistance, continuity)</li><li>Wire cutters/strippers; soldering iron is optional, not needed for the breadboard</li><li>Audio source with a 3.5 mm stereo lead; start at low volume</li><li>Two small 8 Ω speakers (not headphones)</li></ul></div><div class="mini"><h3><span class="icon">◇</span>Know before wiring</h3><ul class="clean"><li>Identify the LM386 notch/dot and count pins counter-clockwise from the notch.</li><li>Read capacitor markings: electrolytics have a marked negative stripe; ceramic capacitors are non-polar.</li><li>Breadboard rows connect internally; power rails may be split in the middle.</li><li>Use one common ground for input, both ICs, supply, and speaker returns.</li></ul></div></div><p class="small">Keep the two speaker wires for each channel paired and away from the input wires. Excessive volume, clipped audio, or shorted outputs can overheat the IC or drain a battery quickly.</p></div></section>
<section id="parts"><div class="section-head"><span class="num">03</span><h2>Complete parts list</h2></div><div class="card"><div class="table-wrap"><table><caption>One stereo build; values shown are practical starting points.</caption><thead><tr><th>Component / part</th><th>Qty.</th><th>Purpose / notes</th></tr></thead><tbody>
<tr><td>LM386N-1 low-voltage audio power amplifier, DIP-8</td><td class="qty">2</td><td>One mono amplifier per channel. Use DIP package for breadboard; verify pin-1 notch.</td></tr>
<tr><td>Solderless breadboard, full-size</td><td class="qty">1</td><td>Temporary construction platform; check whether the red/blue rails are split.</td></tr>
<tr><td>Jumper wires, insulated</td><td class="qty">~20</td><td>Power, ground, signal, and cross-row connections.</td></tr>
<tr><td>10 kΩ audio-taper potentiometer (linear works)</td><td class="qty">2</td><td>Independent left/right volume. Three terminals: input end, ground end, wiper.</td></tr>
<tr><td>10 µF electrolytic, ≥16 V</td><td class="qty">2</td><td>Input coupling: wiper to LM386 pin 3. Positive end faces pin 3.</td></tr>
<tr><td>220 µF electrolytic, ≥16 V</td><td class="qty">2</td><td>Speaker output coupling from pin 5; positive faces the IC output.</td></tr>
<tr><td>10 µF electrolytic, ≥16 V</td><td class="qty">2</td><td>Local bypass from pin 7 to ground; positive to pin 7. Recommended.</td></tr>
<tr><td>100 nF (0.1 µF) ceramic, ≥16 V</td><td class="qty">2</td><td>High-frequency supply decoupling; one close to pins 6 and 4 per IC.</td></tr>
<tr><td>220 µF electrolytic, ≥16 V</td><td class="qty">1</td><td>Bulk decoupling across the shared 9 V and ground rails near the ICs.</td></tr>
<tr><td>10 Ω resistor, ¼ W + 47 nF ceramic capacitor</td><td class="qty">2 each</td><td>Optional Zobel network, in series from each pin 5 to ground; helps output stability with real wiring/speakers.</td></tr>
<tr><td>8 Ω speakers, 0.5 W or greater</td><td class="qty">2</td><td>Small speaker loads, one per channel. Do not substitute a short or a load below 8 Ω.</td></tr>
<tr><td>3.5 mm stereo audio lead / jack</td><td class="qty">1</td><td>Tip = left, ring = right, sleeve = common ground (check your cable).</td></tr>
<tr><td>9 V battery + clip, or regulated 9 V DC supply</td><td class="qty">1</td><td>Positive to VCC rail and negative to common ground. A supply with current limit is preferable.</td></tr>
</tbody></table></div><p class="small">The 220 µF speaker capacitors and 10 µF input/bypass capacitors are polarized. If yours are rated exactly 16 V, they are suitable for this 9 V circuit. Optional Zobel parts are included for robustness; the core circuit can be tested without them.</p></div></section>
<section id="schematic"><div class="section-head"><span class="num">04A</span><h2>Schematic · one channel, duplicated</h2></div><div class="card diagram-card"><div class="diagram-title"><h3>LM386 mono stage × 2</h3><span>Build identical left & right circuits; share only supply, ground, and source ground.</span></div>
<svg class="diagram" viewBox="0 0 900 500" role="img" aria-labelledby="schTitle schDesc"><title id="schTitle">One-channel LM386 schematic</title><desc id="schDesc">Input through volume potentiometer and coupling capacitor to pin 3. Pin 2 and pin 4 grounded. Pin 6 receives 9 volts. Pin 7 has a 10 microfarad bypass. Pin 5 couples through 220 microfarads to an 8 ohm speaker.</desc>
<defs><marker id="arr" viewBox="0 0 10 10" refX="9" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path d="M0 0L10 5 0 10z" fill="#72aaff"/></marker></defs>
<!-- input/pot -->
<text x="26" y="101" class="svg-label">AUDIO IN</text><text x="26" y="120" class="svg-small">L (or R)</text><path d="M95 112H138" class="wire signal"/><circle cx="138" cy="112" r="4" fill="#72aaff"/><path d="M138 112V158H157" class="wire signal"/><rect x="157" y="145" width="92" height="27" rx="5" class="res"/><path d="M249 158V209H260" class="wire gnd"/><path d="M251 209h20m-16 6h12m-8 6h4" stroke="#d2a6ff" stroke-width="2"/><text x="242" y="239" class="svg-tiny">GND end</text><path d="M201 186V163" class="wire signal"/><path d="M195 169l6-8 6 8z" fill="#72aaff"/><path d="M201 186H269V158" class="wire signal"/><text x="164" y="139" class="svg-small">10 kΩ VOL</text><text x="163" y="204" class="svg-tiny">wiper → input cap</text>
<!-- input cap -->
<path d="M269 158H294" class="wire signal"/><path d="M304 145v26m9-26v26" class="cap"/><path d="M313 158H331V122H349" class="wire signal"/><text x="287" y="133" class="svg-small">10 µF</text><text x="299" y="187" class="svg-tiny">+ → pin 3</text>
<!-- chip -->
<rect x="349" y="91" width="212" height="248" rx="15" class="svg-chip"/><path d="M431 91a24 24 0 0 0 48 0" fill="#0c151d" stroke="#5a8393" stroke-width="2"/><text x="455" y="219" text-anchor="middle" class="chiptext">LM386</text><text x="455" y="239" text-anchor="middle" class="svg-small">gain ≈ 20 (pins 1 & 8 open)</text>
<!-- pins labels and lines -->
<path d="M349 122H320" class="wire signal"/><text x="354" y="127" class="svg-tiny">3 +IN</text><path d="M349 164H324V194H299" class="wire gnd"/><text x="354" y="169" class="svg-tiny">2 −IN</text><path d="M349 286H324V307" class="wire gnd"/><text x="354" y="291" class="svg-tiny">4 GND</text><path d="M561 122H610V91" class="wire vcc"/><text x="520" y="117" class="svg-tiny">6 VS</text><path d="M561 164H615" class="wire outwire"/><text x="520" y="159" class="svg-tiny">5 OUT</text><path d="M561 245H603V281" class="wire gnd"/><text x="520" y="240" class="svg-tiny">7 BYPASS</text><text x="520" y="194" class="svg-tiny">1</text><text x="520" y="214" class="svg-tiny">8</text>
<!-- VCC rail and local decouple -->
<path d="M610 91V55H790" class="wire vcc"/><text x="710" y="43" class="svg-label" fill="#ffb66f">+9 V</text><path d="M646 55V104" class="wire vcc"/><path d="M636 104h20m-20 8h20" class="cap"/><path d="M646 112V165" class="wire gnd"/><path d="M638 165h16m-13 6h10m-7 6h4" stroke="#d2a6ff" stroke-width="2"/><text x="661" y="112" class="svg-tiny">100 nF</text><text x="661" y="128" class="svg-tiny">near pins 6/4</text>
<!-- bypass cap -->
<path d="M603 281V296" class="wire gnd"/><path d="M592 296h22m-22 8h22" class="cap"/><path d="M603 304V335" class="wire gnd"/><path d="M595 335h16m-13 6h10m-7 6h4" stroke="#d2a6ff" stroke-width="2"/><text x="620" y="304" class="svg-tiny">10 µF bypass</text><text x="620" y="319" class="svg-tiny">+ to pin 7</text>
<!-- output cap and speaker -->
<path d="M615 164H666" class="wire outwire"/><path d="M676 151v26m9-26v26" class="cap"/><path d="M685 164H729" class="wire outwire"/><text x="667" y="140" class="svg-small">220 µF</text><text x="674" y="192" class="svg-tiny">+ toward pin 5</text><path d="M729 164h15" class="wire outwire"/><path d="M744 145v38l32-19z" fill="#183b2d" stroke="#81e0ad" stroke-width="2"/><path d="M780 151v26m7-31v36" stroke="#81e0ad" stroke-width="2"/><path d="M787 164H814" class="wire outwire"/><path d="M814 164V208" class="wire gnd"/><path d="M806 208h16m-13 6h10m-7 6h4" stroke="#d2a6ff" stroke-width="2"/><text x="731" y="126" class="svg-label">8 Ω SPEAKER</text><text x="790" y="187" class="svg-tiny">return to GND</text>
<!-- common ground -->
<path d="M299 194V400H784M324 307V400M603 335V400M814 208V400" class="wire gnd"/><path d="M533 400v13m-15 0h30m-23 7h16m-11 7h6" stroke="#d2a6ff" stroke-width="2"/><text x="552" y="425" class="svg-label">COMMON GND</text>
<!-- zobel -->
<path d="M615 164V255H665" class="wire" stroke-dasharray="5 5"/><rect x="665" y="244" width="50" height="22" rx="4" class="res"/><path d="M715 255H734" class="wire" stroke-dasharray="5 5"/><path d="M741 244v22m8-22v22" class="cap"/><path d="M749 255H770V400" class="wire" stroke-dasharray="5 5"/><text x="658" y="238" class="svg-tiny">optional: 10 Ω + 47 nF series (Zobel)</text>
<text x="26" y="468" class="svg-small">Repeat this stage for the second channel. The speakers connect to their own output capacitors; do not join the two pin-5 outputs.</text>
</svg><p class="small">Pin numbering is from the top view of a DIP-8 package with the notch at the top: left side 1–4 downward, right side 5–8 upward. Pins 1 and 8 are intentionally unconnected.</p></div></section>
<section id="breadboard"><div class="section-head"><span class="num">04B</span><h2>Breadboard wiring map</h2></div><div class="card diagram-card"><div class="diagram-title"><h3>Two ICs straddling the center trench</h3><span>Illustrative placement—not to scale; follow pin/row labels.</span></div>
<svg class="diagram" viewBox="0 0 900 480" role="img" aria-labelledby="bbTitle bbDesc"><title id="bbTitle">Stereo breadboard layout for two LM386 amplifiers</title><desc id="bbDesc">Two DIP eight LM386 chips sit across the center gap. Top and bottom rails provide shared 9 volt and ground. Input pots, coupling capacitors, output capacitors and speakers are shown for left and right channels.</desc>
<rect x="20" y="25" width="860" height="420" rx="20" fill="#13202a" stroke="#34505e" stroke-width="2"/><rect x="55" y="63" width="790" height="30" rx="8" fill="#1a2932"/><rect x="55" y="387" width="790" height="30" rx="8" fill="#1a2932"/><text x="66" y="83" class="svg-label" fill="#ffb66f">+9 V RAIL</text><text x="66" y="408" class="svg-label" fill="#d2a6ff">GND RAIL (shared)</text><path d="M160 78H818" class="wire vcc"/><path d="M160 402H818" class="wire gnd"/>
<!-- breadboard holes rows -->
<g fill="#38515e"></g>
<rect x="80" y="110" width="740" height="250" rx="10" fill="#101922" stroke="#293d49"/><path d="M80 232H820" stroke="#42535b" stroke-dasharray="4 8" stroke-width="2"/><text x="392" y="248" class="svg-tiny">CENTER TRENCH</text>
<!-- chip left -->
<rect x="264" y="164" width="170" height="61" rx="9" class="svg-chip"/><path d="M329 164a20 20 0 0 0 40 0" fill="#101922" stroke="#5a8393" stroke-width="2"/><text x="349" y="201" text-anchor="middle" class="chiptext">U1 · LEFT</text>
<!-- pins left numbered -->
<g class="svg-tiny" text-anchor="middle"><text x="280" y="157">1</text><text x="310" y="157">2</text><text x="340" y="157">3</text><text x="370" y="157">4</text><text x="400" y="157">5</text><text x="430" y="157">6</text><text x="430" y="244">7</text><text x="400" y="244">8</text></g>
<path d="M280 164V142M310 164V142M340 164V142M370 164V142M400 164V142M430 164V142M430 225V260M400 225V260" stroke="#d3e1e8" stroke-width="2"/><path d="M430 142V78" class="wire vcc"/><path d="M370 142V336H180V402" class="wire gnd"/><path d="M310 142V336" class="wire gnd"/><path d="M340 142H217" class="wire signal"/><path d="M217 142V188" class="wire signal"/><text x="127" y="207" class="svg-small">10 µF input</text><text x="127" y="222" class="svg-tiny">+ to pin 3</text><path d="M217 142H179V125" class="wire signal"/><circle cx="179" cy="125" r="5" fill="#72aaff"/><text x="105" y="118" class="svg-small">LEFT POT wiper</text><path d="M400 142V118H502" class="wire outwire"/><path d="M502 118v-12m8 0v24" class="cap"/><path d="M510 118H552" class="wire outwire"/><path d="M552 101v34l28-17z" fill="#183b2d" stroke="#81e0ad" stroke-width="2"/><path d="M580 118h20" class="wire outwire"/><text x="462" y="95" class="svg-tiny">220 µF +</text><text x="590" y="100" class="svg-small">LEFT 8 Ω</text><path d="M600 118V336H180" class="wire gnd"/>
<!-- left bypass -->
<path d="M430 260V291" class="wire gnd"/><path d="M421 291h18m-18 7h18" class="cap"/><path d="M430 298V336" class="wire gnd"/><text x="441" y="296" class="svg-tiny">10 µF</text>
<!-- chip right -->
<rect x="264" y="267" width="170" height="61" rx="9" class="svg-chip"/><path d="M329 267a20 20 0 0 0 40 0" fill="#101922" stroke="#5a8393" stroke-width="2"/><text x="349" y="305" text-anchor="middle" class="chiptext">U2 · RIGHT</text>
<g class="svg-tiny" text-anchor="middle"><text x="280" y="260">1</text><text x="310" y="260">2</text><text x="340" y="260">3</text><text x="370" y="260">4</text><text x="400" y="260">5</text><text x="430" y="260">6</text><text x="430" y="347">7</text><text x="400" y="347">8</text></g>
<path d="M280 267V245M310 267V245M340 267V245M370 267V245M400 267V245M430 267V245M430 328V356M400 328V356" stroke="#d3e1e8" stroke-width="2"/><path d="M430 245V78" class="wire vcc"/><path d="M370 245V366H180V402" class="wire gnd"/><path d="M310 245V366" class="wire gnd"/><path d="M340 245H217V278" class="wire signal"/><path d="M217 245H179V232" class="wire signal"/><circle cx="179" cy="232" r="5" fill="#72aaff"/><text x="97" y="225" class="svg-small">RIGHT POT wiper</text><text x="105" y="298" class="svg-small">10 µF input</text><text x="105" y="313" class="svg-tiny">+ to pin 3</text>
<path d="M400 245V230H502" class="wire outwire"/><path d="M502 230v-12m8 0v24" class="cap"/><path d="M510 230H552" class="wire outwire"/><path d="M552 213v34l28-17z" fill="#183b2d" stroke="#81e0ad" stroke-width="2"/><path d="M580 230h20" class="wire outwire"/><text x="462" y="207" class="svg-tiny">220 µF +</text><text x="590" y="212" class="svg-small">RIGHT 8 Ω</text><path d="M600 230V366H180" class="wire gnd"/>
<path d="M430 356V366" class="wire gnd"/><path d="M421 356h18m-18 7h18" class="cap"/><text x="441" y="359" class="svg-tiny">10 µF</text>
<!-- input jack / pot symbols and legend -->
<path d="M90 142H147" class="wire signal"/><text x="84" y="135" class="svg-tiny">TIP = L</text><path d="M90 252H147" class="wire signal"/><text x="84" y="266" class="svg-tiny">RING = R</text><path d="M91 160V377H180" class="wire gnd"/><text x="92" y="179" class="svg-tiny">SLEEVE</text><text x="91" y="193" class="svg-tiny">= GND</text>
<text x="626" y="290" class="svg-small">Both speaker returns</text><text x="626" y="307" class="svg-small">to common GND rail.</text><text x="626" y="340" class="svg-tiny">U1 / U2 pin 4 → GND</text><text x="626" y="356" class="svg-tiny">pin 6 → +9 V · pin 2 → GND</text>
<text x="64" y="438" class="svg-tiny">Add 100 nF directly between each IC's pin 6 and ground; pin 7 bypass caps go to ground (positive at pin 7).</text>
</svg><p class="small">Breadboard rows vary by model. This is a connection map, not a promise that every visible hole shares the pictured row. Check continuity on your breadboard and connect each labeled pin to the named rail/node. Keep pin 5 outputs separate.</p></div></section>
<section id="assembly"><div class="section-head"><span class="num">05</span><h2>Step-by-step assembly</h2></div><div class="card"><ol class="steps">
<li><strong>Power off; map your board.</strong><p>Disconnect the battery/supply. Use the multimeter’s continuity mode to identify connected tie rows and any split power rails. Mark a +9 V rail and a common ground rail.</p></li>
<li><strong>Place both LM386s across the center trench.</strong><p>Seat each DIP-8 so four legs are on either side of the trench. Orient both notches the same way. Identify pins 1–8 from the notch; confirm pin numbers against the schematic before adding wires.</p></li>
<li><strong>Make the shared supply and grounds.</strong><p>Connect the positive supply rail to pin 6 of both ICs. Connect pins 4 and 2 of both ICs to the ground rail. Keep pins 1 and 8 open. Do not connect power yet.</p></li>
<li><strong>Add supply decoupling.</strong><p>Place one 100 nF ceramic capacitor close to each IC, between pin 6 / +9 V and ground. Add the 220 µF bulk capacitor across the rails: positive to +9 V, negative stripe to ground. If rails are split, jumper the halves together.</p></li>
<li><strong>Wire the bypass pins.</strong><p>For each IC, place a 10 µF electrolytic from pin 7 to ground, positive lead at pin 7. This helps suppress supply-related noise; do not confuse pin 7 with the output at pin 5.</p></li>
<li><strong>Wire the two volume controls and inputs.</strong><p>For each 10 kΩ pot, connect one outer lug to its channel signal (tip for left, ring for right), the other outer lug to ground, and the center lug (wiper) through a 10 µF input capacitor to pin 3. Put the capacitor’s positive lead toward pin 3. Connect the audio cable sleeve to common ground. Leave pin 2 grounded.</p></li>
<li><strong>Connect the speaker outputs.</strong><p>For each channel, wire pin 5 through a 220 µF electrolytic to that channel’s speaker positive terminal; the capacitor positive lead faces pin 5. Connect the speaker’s other terminal to common ground. Never connect a speaker directly between the two IC outputs. If fitting the optional Zobel network, wire 10 Ω in series with 47 nF from pin 5 to ground.</p></li>
<li><strong>Inspect before power.</strong><p>Check every pin and capacitor polarity against the diagram. Ensure the +9 V and ground rails are not shorted; confirm the two pin-5 output nodes are not joined. Turn both pots fully down and unplug the audio source.</p></li>
<li><strong>Power and bring up the sound gently.</strong><p>Connect a 9 V battery or set a current-limited bench supply to 9 V with a conservative limit (about 200–300 mA for initial checks). Verify supply polarity and voltage at both pin-6 nodes. Connect the audio source at low output level, then slowly raise the volume.</p></li>
</ol></div></section>
<section id="testing"><div class="section-head"><span class="num">06</span><h2>Testing & troubleshooting</h2></div><div class="card"><h3 style="margin:0 0 12px">Before you switch on</h3><div class="checklist"><div class="check"><b>✓</b>Supply is 9 V DC, correct polarity</div><div class="check"><b>✓</b>Pin 6 gets +V; pin 4 and pin 2 go to ground</div><div class="check"><b>✓</b>Electrolytic stripe / polarity checked</div><div class="check"><b>✓</b>8 Ω speaker on each separate output</div><div class="check"><b>✓</b>Input sleeve, ICs, and supply share ground</div><div class="check"><b>✓</b>Volume at minimum; audio source unplugged initially</div></div><div class="callout"><strong>First power-up:</strong> With speakers disconnected, power the circuit and measure the DC voltage at pin 5 of each LM386 relative to ground. It should sit around half the supply (roughly 3–5 V on a 9 V supply). The 220 µF output capacitor blocks this DC from reaching the speaker. Power down before reconnecting or moving wires.</div><div class="trouble"><article><h3>No sound in either channel</h3><p>Check battery voltage, the common ground, pin-6 supply, audio cable sleeve, source output level, and that pin 3—not pin 2—receives the coupled signal. Verify the rail isn’t split.</p></article><article><h3>Only one channel works</h3><p>Swap left/right input leads to isolate the source from the amp. Inspect that channel’s pot wiper, input-capacitor polarity, pin-5 output capacitor, and speaker wiring.</p></article><article><h3>Hum, hiss, or oscillation</h3><p>Use short input wires and a common ground; keep input wiring away from speaker/output wiring. Confirm local 100 nF decouplers are close to the ICs, add the Zobel network, and avoid excessive gain or volume.</p></article><article><h3>Distorted sound / hot IC</h3><p>Lower source and pot volume; clipping is common when pushed hard. Check for an output short, wrong speaker impedance, reversed electrolytics, incorrect pin orientation, or a supply above the part’s rating.</p></article><article><h3>Pop, crackle, or intermittent audio</h3><p>Reseat the ICs and jumpers, check pot connections and breadboard contacts, and inspect for loose speaker terminals. Power down before adjusting wiring.</p></article><article><h3>Unexpected DC at speaker</h3><p>Check the 220 µF output capacitor is in series and positive toward pin 5. Do not connect a speaker directly to pin 5. A multimeter should show near-zero DC across the speaker after the coupling capacitor.</p></article></div><div class="callout warning"><strong>Stop if anything gets hot, smells, or draws unexpectedly high current.</strong> Disconnect power, let capacitors discharge, and recheck pin orientation, rail shorts, capacitor polarity, and speaker load before trying again.</div></div></section>
<footer class="footer"><strong>Build note:</strong> The LM386 is a mono IC, so this stereo circuit uses two independent devices. This breadboard design is for learning and modest listening levels; use a purpose-designed amplifier for demanding speakers or sustained high output.</footer>
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