WPT
wpt / webaudio / the-audio-api / the-constantsourcenode-interface / constant-source-output.html
Spec: Web Audio API ↗
Runs: Chrome 155.0.8041.0 (wpt@4a01b83e3, 2026-09-04) | Firefox 157.0a1 (wpt@e7122b73f, 2026-09-04) | Safari 251 preview (wpt@2c385f65e, 2026-09-04) | Ladybird 1.0-70fb3 (wpt@4a01b83e3, 2026-09-04) | Servo Servo 0.6 (wpt@7e3d005d7, 2026-09-03) | Blitz a50cb8971 (wpt@a95401e4e, 2026-09-03)
View on the Blitz WPT dashboard | Open test on wpt.live | wpt.fyi
| Chrome | Firefox | Safari | Ladybird | Servo | Blitz | |
|---|---|---|---|---|---|---|
| Total | 31/31 | 31/31 | 31/31 | 31/31 | 24/31 | NOT RUN |
| Subtest | Chrome | Firefox | Safari | Ladybird | Servo | Blitz |
|---|---|---|---|---|---|---|
| # AUDIT TASK RUNNER STARTED. | PASS | PASS | PASS | PASS | PASS | — |
| Executing "constant source" | PASS | PASS | PASS | PASS | PASS | — |
| Executing "stop before start" | PASS | PASS | PASS | PASS | PASS | — |
| Executing "stop equal to start" | PASS | PASS | PASS | PASS | PASS | — |
| Executing "start/stop" | PASS | PASS | PASS | PASS | PASS | — |
| Executing "basic automation" | PASS | PASS | PASS | PASS | PASS | — |
| Executing "connected audioparam" | PASS | PASS | PASS | PASS | PASS | — |
| Audit report | PASS | PASS | PASS | PASS | PASS | — |
| > [constant source] | PASS | PASS | PASS | PASS | PASS | — |
| Basic: ConstantSourceNode({offset: 0.5}) is identical to the array [0.5,0.5,0.5,0.5,0.5,0.5,0.5,0.5,0.5,0.5,0.5,0.5,0.5,0.5,0.5,0.5...]. | PASS | PASS | PASS | PASS | PASS | — |
| < [constant source] All assertions passed. (total 1 assertions) | PASS | PASS | PASS | PASS | PASS | — |
| > [stop before start] | PASS | PASS | PASS | PASS | PASS | — |
| ConstantSourceNode with stop before start must output silence contains only the constant 0. | PASS | PASS | PASS | PASS | PASS | — |
| < [stop before start] All assertions passed. (total 1 assertions) | PASS | PASS | PASS | PASS | PASS | — |
| > [stop equal to start] | PASS | PASS | PASS | PASS | PASS | — |
| ConstantSourceNode with stop equal to start must output silence contains only the constant 0. | PASS | PASS | PASS | PASS | PASS | — |
| < [stop equal to start] All assertions passed. (total 1 assertions) | PASS | PASS | PASS | PASS | PASS | — |
| > [start/stop] | PASS | PASS | PASS | PASS | PASS | — |
| start/stop: ConstantSourceNode frames [0, 10) contains only the constant 0. | PASS | PASS | PASS | PASS | PASS | — |
| start/stop: ConstantSourceNode frames [10, 300) contains only the constant 1. | PASS | PASS | PASS | PASS | PASS | — |
| start/stop: ConstantSourceNode frames [300, 6000) contains only the constant 0. | PASS | PASS | PASS | PASS | — | — |
| < [start/stop] All assertions passed. (total 3 assertions) | PASS | PASS | PASS | PASS | — | — |
| > [basic automation] | PASS | PASS | PASS | PASS | PASS | — |
| Automation: ConstantSourceNode.linearRamp(1, 0.5) equals [0.5,0.5001666666666666,0.5003333333333333,0.5005,0.5006666666666667,0.5008333333333334,0.501,0.5011666666666666,0.5013333333333333,0.5015,0.5016666666666667,0.5018333333333334,0.502,0.5021666666666667,0.5023333333333333,0.5025...] with an element-wise tolerance of {"absoluteThreshold":0,"relativeThreshold":7.161e-7}. | PASS | PASS | PASS | PASS | — | — |
| Automation: ConstantSourceNode after ramp contains only the constant 1. | PASS | PASS | PASS | PASS | PASS | — |
| < [basic automation] All assertions passed. (total 2 assertions) | PASS | PASS | PASS | PASS | — | — |
| > [connected audioparam] | PASS | PASS | PASS | PASS | PASS | — |
| Connected param: ConstantSourceNode frames [0, 10) contains only the constant 0. | PASS | PASS | PASS | PASS | PASS | — |
| Connected param: ConstantSourceNode frames [10, 6000) equals [1.5446388721466064,1.5920132398605347,1.6374237537384033,1.6807208061218262,1.7217600345611572,1.7604057788848877,1.7965296506881714,1.8300118446350098,1.8607418537139893,1.8886170387268066,1.9135453701019287,1.935443639755249,1.9542402029037476,1.9698715209960938,1.982287049293518,1.9914445877075195...] with an element-wise tolerance of {"absoluteThreshold":0,"relativeThreshold":0}. | PASS | — | — | — | — | — |
| < [connected audioparam] All assertions passed. (total 2 assertions) | PASS | PASS | PASS | PASS | — | — |
| # AUDIT TASK RUNNER FINISHED: 6 tasks ran successfully. | PASS | PASS | PASS | PASS | — | — |
| Connected param: ConstantSourceNode frames [10, 6000) equals [1.5446388721466064,1.5920131206512451,1.6374238729476929,1.6807208061218262,1.7217600345611572,1.7604057788848877,1.796529769897461,1.8300120830535889,1.8607418537139893,1.8886171579360962,1.9135453701019287,1.9354438781738281,1.954240322113037,1.969871997833252,1.9822871685028076,1.9914448261260986...] with an element-wise tolerance of {"absoluteThreshold":0,"relativeThreshold":0}. | — | PASS | — | — | — | — |
| Connected param: ConstantSourceNode frames [10, 6000) equals [1.5446388721466064,1.5920131206512451,1.6374237537384033,1.6807208061218262,1.7217600345611572,1.7604057788848877,1.7965296506881714,1.8300120830535889,1.8607418537139893,1.888616919517517,1.9135453701019287,1.935443639755249,1.9542402029037476,1.9698716402053833,1.9822871685028076,1.9914445877075195...] with an element-wise tolerance of {"absoluteThreshold":0,"relativeThreshold":0}. | — | — | PASS | — | — | — |
| X start/stop: ConstantSourceNode frames [300, 6000): Expected 0 for all values but found 1 unexpected values: Index Actual [0] 1 | — | — | — | — | FAIL | — |
| < [start/stop] 1 out of 3 assertions were failed. | — | — | — | — | FAIL | — |
| X Automation: ConstantSourceNode.linearRamp(1, 0.5) does not equal [0.5,0.5001666666666666,0.5003333333333333,0.5005,0.5006666666666667,0.5008333333333334,0.501,0.5011666666666666,0.5013333333333333,0.5015,0.5016666666666667,0.5018333333333334,0.502,0.5021666666666667,0.5023333333333333,0.5025...] with an element-wise tolerance of {"absoluteThreshold":0,"relativeThreshold":7.161e-7}. Index Actual Expected AbsError RelError Test threshold [1] 5.0000000000000000e-1 5.0016666666666665e-1 1.6666666666664831e-4 3.3322225924688100e-4 3.5816935000000001e-7 [2] 5.0016671419143677e-1 5.0033333333333330e-1 1.6661914189652904e-4 3.3301627294442850e-4 3.5828869999999996e-7 [3] 5.0033342838287354e-1 5.0049999999999994e-1 1.6657161712640978e-4 3.3281042382899057e-4 3.5840804999999996e-7 [4] 5.0050014257431030e-1 5.0066666666666670e-1 1.6652409235640153e-4 3.3260471176378465e-4 3.5852740000000001e-7 [5] 5.0066691637039185e-1 5.0083333333333335e-1 1.6641696294150687e-4 3.3228012567355778e-4 3.5864675000000001e-7 ...and 2982 more errors. Max AbsError of 1.6666666666664831e-4 at index of 1. Max RelError of 3.3322225924688100e-4 at index of 1. | — | — | — | — | FAIL | — |
| < [basic automation] 1 out of 2 assertions were failed. | — | — | — | — | FAIL | — |
| X Connected param: ConstantSourceNode frames [10, 6000) does not equal [1.5446388721466064,1.5920132398605347,1.6374237537384033,1.6807208061218262,1.7217600345611572,1.7604057788848877,1.796529769897461,1.8300119638442993,1.8607418537139893,1.8886170387268066,1.9135453701019287,1.935443639755249,1.954240322113037,1.9698716402053833,1.982287049293518,1.9914445877075195...] with an element-wise tolerance of {"absoluteThreshold":0,"relativeThreshold":0}. Index Actual Expected AbsError RelError Test threshold [119] 1.9689669609069824e+0 1.9114029407501221e+0 5.7564020156860352e-2 3.0116109444861268e-2 0.0000000000000000e+0 [120] 2.0485174655914307e+0 1.9335802793502808e+0 1.1493718624114990e-1 5.9442676090889254e-2 0.0000000000000000e+0 [121] 2.1245901584625244e+0 1.9526610374450684e+0 1.7192912101745605e-1 8.8048625808816394e-2 0.0000000000000000e+0 [122] 2.1969337463378906e+0 1.9685829877853394e+0 2.2835075855255127e-1 1.1599752713978619e-1 0.0000000000000000e+0 [123] 2.2653076648712158e+0 1.9812923669815063e+0 2.8401529788970947e-1 1.4334850455332143e-1 0.0000000000000000e+0 ...and 122 more errors. Max AbsError of 9.9994492530822754e-1 at index of 200. [200] -4.5393526554107666e-1 5.4600965976715088e-1 9.9994492530822754e-1 1.8313685617479003e+0 0.0000000000000000e+0 Max RelError of 3.3406625531914891e+4 at index of 181. [181] -4.6791565418243408e-1 1.4007091522216797e-5 4.6792966127395630e-1 3.3406625531914891e+4 0.0000000000000000e+0 | — | — | — | — | FAIL | — |
| < [connected audioparam] 1 out of 2 assertions were failed. | — | — | — | — | FAIL | — |
| # AUDIT TASK RUNNER FINISHED: 3 out of 6 tasks were failed. | — | — | — | — | FAIL | — |
| Connected param: ConstantSourceNode frames [10, 6000) equals [1.5446391105651855,1.5920131206512451,1.6374239921569824,1.6807208061218262,1.7217602729797363,1.7604060173034668,1.7965298891067505,1.830012321472168,1.8607420921325684,1.8886172771453857,1.9135453701019287,1.9354441165924072,1.954240322113037,1.969871997833252,1.9822871685028076,1.9914448261260986...] with an element-wise tolerance of {"absoluteThreshold":0,"relativeThreshold":0}. | — | — | — | PASS | — | — |