LTX V2 Fast sells six to twenty seconds at 4 credits

ltxv2-text-to-video-fast is 4K, native audio, 6s through 20s at 4 credits; the Pro T2V row next to it is 6 credits and only 6 / 8 / 10s.

The two LTX text-to-video cards sit next to each other and look interchangeable until you read the duration list. Fast is the long ladder. Pro is the short one. Both return a mix. Neither takes a still. Pick the row from the length you can actually use, not from the word “Pro.”

Fast is 4K, audio-on, 6s through 20s at 4 credits

LTX 2 Text to Video Fast is LTX's fast text-to-video row: “Fast text-to-video generation with LTXV2,” no still required, 4K ceiling, 4 credits, audio true. Duration is an even ladder: 6s, 8s, 10s, 12s, 14s, 16s, 18s, 20s. There is no 4s, no 5s, no 7s, no 9s on this record. Twenty seconds is the ceiling. Four credits is the catalog display price. Fast is a listed feature. Silent is not.

Native audio is on. A picture-only prompt still returns a mix the model chose. Write the room, quote the line, name the hits — or plan to replace the track. “Silence” is a cue you write. Omitting sound is not a mute switch.

Quality settings listed are 1080p, 1440p, and 2160p — that last one is the 4K tier. Motion level listed is Medium only. Styles listed are Cinematic, Documentary, and Abstract. Frame rates listed are 24fps and 30fps. Those are the knobs. They do not include “no audio.” Do not prompt a crash pan and then call the row broken.

No image is required. If the product must match a locked still, leave this row. The AI video generator will run it quickly. It will not write the sound clause for you. Fast, 4 credits, audio on. Pick 6s, 8s, or 10s unless you can name why 14s or 20s is the shot. Do not spend 4 credits on a 20-second wander because Fast made the slider feel free.

Pro next to it is 6 credits and only 6 / 8 / 10s

LTX 2 Text to Video Pro is professional text-to-video with LTXV2. Category text-to-video. No still required. audio true. Durations: 6s, 8s, 10s. Max output: 4K. Quality chips: 1080p, 1440p, 2160p. Frame rates: 24fps, 30fps. Motion levels: Medium and High. Display price: 6 credits. Styles: Cinematic, Documentary, Abstract.

Pro is not “Fast plus two credits of mute polish.” Pro is the same family with a shorter ladder and a High motion chip. There is no 12s, no 14s, no 16s, no 18s, no 20s on this slug. A 12-second idea does not belong here. Climb Fast, or cut the idea to 10s, or use a different family. Do not prompt Pro into 20s. Change the row.

Both rows invent the scene from text. Both return a soundtrack. If you have a locked plate, confirm you wanted text-to-video at all. Neither slug will honor a product still you forgot to attach, because neither requires one. Identity-hold work is image-to-video on a different card.

Use Pro when 6s, 8s, or 10s is the whole shot and you want the High motion option. Use Fast when the beat actually needs 12s through 20s, or when 4 credits is the test you meant to buy. Documentary, Abstract, and Cinematic still get audio. Style is a picture register. The audio flag does not follow it.

Seven seconds still buys a stair

Neither row sells 7s. Fast steps by twos from 6s to 20s. Pro offers 6s, 8s, and 10s only. A seven-second idea still buys 8s.

A 7-second clip on a tiered model is the cost shape: duration sold in whole units, not a linear trim. The staircase, and the second that costs a full step. Fit the idea to a chip that exists. Do not “need 7” and pay 8 by accident, then climb to 20 on Fast because the catalog price stayed 4 credits. Twenty seconds is a different shot. It is not a free leftover on a 7-second brief.

Write the cue to the length you picked. A 6-second Fast take with a written mix is the default test. An 8-second take is the 7-second brief, rounded up. A 10-second take is the top of Pro and one more even step on Fast. Climb past 10s only on Fast, and only when the action actually lasts.

Do not mix the meters. Fast is not a per-second discount you invent from the 4-credit display. Pro is not a 20-second row you invent from the 4K chip. Read the duration list before you dispatch.

Write the mix; Fast is not mute coverage

Unmute the take before you caption it. If the unmuted version contains a riser, a line, or a room you cannot ship, the prompt was incomplete. Put the sound in the next run. Do not “fix it in captions.” Captions will transcribe the line you did not write.

A useful Fast prompt names the action that fits the length you picked, the camera, and the soundtrack. Medium motion only. 4K ceiling. 4 credits. Audio on. A useful Pro prompt does the same in 6s, 8s, or 10s, at 6 credits, with Medium or High. If the job is a silent product turn off a locked still, this family is the wrong family. Pick the length first. Same vendor. Different ladders.

FAQ

If I omit sound, is LTX 2 Fast silent?

No. Native audio is on. A silent prompt still gets a soundtrack you did not choose. The same is true of Pro. Write the cue, or write silence.

Can I run 4s, 5s, or 7s on Fast?

No. Supported durations start at 6s and step by twos to 20s. A 7-second need buys 8s. Shorter clips are a different model. See 7-second clips on a tiered model.

Does Pro go to 20s if I pay 6 credits?

No. Pro durations are 6s, 8s, 10s at 6 credits, 4K, native audio. Twelve through twenty seconds is the Fast ladder at 4 credits, not a Pro prompt trick.

Do I need an image on either row?

No. Both are text-to-video. A locked still belongs on an image-to-video or reference row. Fast will not hold a product plate you never attached.