Newbie Bard/Lock, regarding Spell Foci

[Polarthief]

Hey everyone, new to both this forum (as a poster, been reading as research!) and D&D in general! I am in the process of making my first character ever (Lore Bard/Tome Lock) and I have some questions that I'd like answered before I finalize my character.

1. I know that a Warlock uses an Arcane Focus for their spellcasting, but could said focus be a musical instrument?

2. If no to the above, could I simply buy an Arcane Focus crystal and attach it to my Lyre/Lute/etc instruments I play? (e.g., if it's a necklace/amulet, could I just put it on the instrument?)

3. Because playing an instrument requires both my hands (though this fulfills both the Somatic and Material components I assume), whenever I cast a spell, I have to drop whatever other weapons or items I am holding, correct? Or, can I simply hold the instrument to cast spells? (My hands will usually be holding a Rapier and either a Lute or Lyre)

4. If a spell requires no material component and #1 or #2 works fine, if I wanted to cast, say, Eldritch Blast, would I be able to while holding both my Rapier and arcane-crystal-holding/infused instrument?

I'm sorry if these are basic questions, but I've been scrambling to make sure I won't be completely screwed for Somatic and Material parts of a spell, especially if I'm holding both a Rapier and instrument.

[Iguanodon]

Spell foci are technically tied to specific spellcasting classes (like, you can't use a holy symbol to cast Wizard spells). However, in my experience only the most draconian DMs really make bards keep track of which hands they are holding their instruments in. Remember you get a free object interaction each round; this is sufficient in most cases.

One-handed musical instruments exist (though maybe not explicitly listed in the 5e books), so it should be possible to wield a rapier and instrument at once.

Remember that you can still use a spell component pouch for both classes if you want. This might be a good backup to carry around just in case.

Spell foci only work for spells with BOTH a somatic and material component.

In summary:

No.
Likely yes; ask your DM. They may require that you specifically handle the focus. If this is the case, tape a wand to your violin bow.
This depends on the instrument. My guess is actually playing is required.
If a spell has no material component, you need a free hand to cast its somatic components; no focus will do. Keep your saxophone on a neck strap to avoid using an object interaction to pick it up.

[Polarthief]

If a spell has no material component, you need a free hand to cast its somatic components; no focus will do. Keep your saxophone on a neck strap to avoid using an object interaction to pick it up.

Non-Material Somatic spells won't let me cast a spell through my Lyre? Oh man, this is just.. balls. Basically what you're saying is I should get War Caster ASAP, lol. The only problem I have about asking DM stuff is that I believe we're trying to do Adventure's League, so it won't be as flexible as I'd like it (if I ever do DM in the future, I'm going to make the game as hassle free as possible because I'm not a huge fan of the small hang-ups RAW interfering with fun).

Thank you for your help though! I guess I can just get a component pouch to wear as a belt or something, but that won't help much when I'm holding a lute and rapier.

Edit: Wait, now that I think about it, what benefit do I get from holding an instrument? Wouldn't it make more sense to just hold my rapier and have a free hand ready for spells/component pouch? It seems like the instrument is more of a detriment than having nothing, and this way, I wouldn't be forced to pick up War Caster (it's still a great feat, but if I have a free hand, it's not as mandatory).

[lebefrei]

Yes, for your case with two different spellcasting classes forget the instrument unless it is vital to your roleplaying. I am more strict in Adventurer League games, as are many DMs, and a component pouch fixes your issues.

[JeffreyGator]

depending on what you are casting, this won't matter much.

Starting out, I use Vicious mockery, Dissonant whispers and Healing word most often in cases when I would have a weapon equipped. these are all V spells...

[bardo]

Pretty much everybody assumes playing is involved, but actually there's no explicit rule saying you need to play the instrument to use it as a spellcasting focus. It doesn't even say you need to be proficient with that instrument to use it as a focus. Assuming your DM will say you have to be proficient and play, since you mentioned AL.

Most instruments in the PHB (chapter 5, under tools) require two hands to play, but...

A horn or a pan flute worn on a necklace around your neck works well as a focus. The instrument hangs over your chest, which is great if you're going for that Viking or Pixie look. You spend your item interaction to grab the instrument, then you can cast your spell, then it's free to drop the instrument and it returns to hanging over your chest.

A drum (think mini-bongos) tied on your belt can be played with one free hand, no need to spend your item interaction.

The description under Musical Instrument in chapter 5 strongly suggests the list isn't exhaustive ("several of the most common types of musical instruments are shown"). Ask your DM about adding other era-appropriate musical instruments. Whistles come to mind as a simple instrument that exists in most settings. Some whistles are played just with the mouth (no holes to cover), so maybe a whistle ring could be a thing. You just wear it on your finger and bring your hand to your mouth to play.

On the warlock side, you could wear a crystal on a necklace, same as a horn or a pan flute. You could hold a wooden wand in your hand for casting warlock spells and beat a drum with that wand to cast bard spells. The Arcane Focus description also strongly suggests it's not an exhaustive list ("or some similar item"). Maybe you can use a ring. Wear one arcane ring and one whistle ring on your off hand.

Necklace works RAW. The drum/wand combo is also RAW. The rest requires some DM fiat but it's well-supported to ask for other types of musical instruments and other arcane foci. Worst thing that could happen is the DM says no.

As other have noted, spell component pouch is so much more practical. If you take Valor Bard then you will need Warcaster to wield weapon, shield, and cast at the same time, and spell component pouch is your only option.

Bardo.

[RickAllison]

If you haven't taken anything from the Elemental Evil Player's Companion, you could always take the shawm! It's a precursor to the oboe that was anywhere from large enough to dwarf a person to small enough to play with one hand.