Some UAD plug-ins introduce additional latency within the plug-in itself (in addition to hardware I/O buffering latency) to achieve sonic design goals. When these plug-ins are used in a DAW and/or Apollo’s Console, the additional latency is induced in the signal path. Therefore, they require more compensation to remain perfectly synchronized with other tracks, versus UAD plug-ins that do not have additional latency.
Note: Compensating for the additional latency from these UAD plug-ins is performed automatically by the host software application (DAW and/or Apollo’s Console) when the latency delay compensation function is enabled in the host.
Although the latency added by these UAD plug-ins is negligible (typically between 0 – 100 samples, depending on the plug-in and session sample rate), if this extra latency is not compensated, it can affect phase coherency in a session.
The additional latency values, in samples, of UAD plug-ins with additional latency are listed in the tables below for the benefit of users with plug-in host DAWs that do not perform automatic delay compensation.
EMT 250 and Lexicon Notes
The EMT 250, Lexicon 224, and Lexicon 480L anti-aliasing filters for their A/D and D/A conversion are not linear-phase filters; therefore the emulations do not have a latency that is the same at all frequencies. Thus, they cannot report to the delay compensation engines a delay that is correct for all frequencies. The reported values are good at low frequencies, but become off at high frequencies.
For example, when the EMT 250 plug-in is in Delay program mode and set with zero delay time and predelay values, the plug-in output will not be completely cancelled when mixing with inverted polarity against an unprocessed track; high frequencies will leak through. However, the latency through the dry side of the wet/dry mix, and the latency when the plug-in is bypassed via the EMT 250 Power switch, do not have this issue and will be fully compensated by the DAW.
Additional UAD Latency Values Table
|UAD Plug-In||Sample Rate (kHz)|
API 550A EQ
API 560 EQ
API Vision Channel Strip
API Vision Channel Strip Legacy
Avalon VT-737sp Channel Strip
Century Tube Channel Strip
Empirical Labs Distressor
Empirical Labs FATSO Jr./Sr.
Helios Type 69
Hitsville EQ Mastering
Manley Massive Passive
Manley Reference Microphone Preamplifier
Manley Variable Mu
Moog Multimode Filter
Moog Multimode Filter XL
Neve 2254 E
Neve 2254 E Dual
Neve 33609 C
SSL 4000 E Preamp & Channel Strip
SSL G Bus Compressor
Thermionic Culture Vulture
UA 1176 Rev A
UA 1176LN Rev E
Helios Type 69
Neve 1073 Legacy
Pultiec EQP-1A Legacy
SSL E Channel Strip Legacy
Teletronix LA-2A Gray
Teletronix LA-2A Silver
Hitsville Reverb Chambers
|Fender ‘55 Tweed Deluxe||119||201||284|
Ibanez Tube Screamer TS808
|Korg SDD-3000 Delay||119||183||344|
|Little Labs IBP||32||14||1|
|Ocean Way Studios||192||688||1568|
|AKG BX 20||983||974||2078||2060||4156||4120|
|Lexicon 224 (see note at the beginning of article)||84||79||90||97||107||116|
|EMT 250† (see notes)||75||11||85||24||107||50|
|Lexicon 480L (see note at the beginning of article)||121||64||177||174||289||284|