Tube Lab

[@audiorick841]

Congrats on your new preamp. It looks amazing! Big congrats as well for your 200th episode and all the great work and knowledge sharing you do.

[@cdbeen123]

congrats on the 200th guys, love your work

[@sean_heisler]

Congrats on 200, fellas!!! The new preamp looks great!

[@garyedwards9617]

Yea 200 !!! :)

[@matthewhilty4209]

Wow my favorite tubes . Looks nice .

[@drdyna]

What a sassy looking pre, I'd love to build one.

[@regaldf.9493]

Congrats on the 200th!

[@johnminassian4887]

With that kind of gain I am thinking this may be a good match for my diyaudio First Watt F4 which is a power buffer that has a slight negative gain. 28 volts would drive the F4 to full output (40 watts per channel into a 4 ohm load). Excellent!

[@jochgemvandelft944]

Congrats on this new design. I do have a few Philips E182CC's lying around. These might be a good replacement for the 6N6Ps right?

[@tubelab194]

@@jochgemvandelft944 no the E182cc has a different pinout. And given how plentiful the vintage 6n6p's are and how good they sound, it wouldn't make any sense to use a different tube.

[@jochgemvandelft944]

Yeah, thanks. I do have a quad of 6N6P as well. And one 6N6P-I.

[@rickg8015]

That preamp is really cute.. Could you upload a sound demo with a 6BZ7/6BQ7 gain stage and a 6CG7 CF output? How much do you think will the whole kit package would weigh for us international buyers?

[@tubelab194]

@@rickg8015 The sound demo's are only so useful using KZbin, but when we make the store listing, later this Fall, I'll try and remember to get Charles to include a selection of high res tracks with various preamp tubes (good idea). The cathode follower will be fixed at the 6N6P, I doubt a better tube exists for the CF stage and it may well be a big part of the great sound.

[@bst8733]

Beautiful design! Is a Phono pre in the works, with this footprint?

[@tubelab194]

@@bst8733 yes on my lab bench is a prototype of our much loved 6or12SL7 Kit Phono Pre, that we're planning on dropping into the Modern Line chassis. It'll be the next size up, but same basic construction.

[@bst8733]

@@tubelab194 Can't wait to see (and hear) it! Size is, unfortunately, a limiting factor for me, so hopefully this one will make the credenza! Thanks for the update!

[@NosEL34]

I watched the other video 1st 🤷 I like how you basically gave the preamp a high gain option. In a preamp like this, where the gain stage is a single dual triode tube, working in stereo, How balanced does that one tube need to be? At what point or percentage of being unbalanced do you consider the tube unusable in this type circuit?

[@tubelab194]

@@NosEL34 close matched in our store is 5% or better (10% for rare tubes) Some circuits like our Universal 6or12SN7 Pre can use mismatched balanced tubes (85/95, 85/95), but the new Modern Line 6N1P/6N6P will require the sections close matched. Luckily you only need two tubes and we have NOS cases of both types. And they're affordable!

[@Pksparty2112]

Looks like the el34 didn’t last long

[@tubelab194]

@@Pksparty2112 please clarify > when writing comments make sure to place the context in your comment, or no one including me can understand what you're saying. Thanks Jim

[@Pksparty2112]

@@tubelab194 I went to your site to look at the el34s in your video and the el34s in the pulldown listed as discounted were marked as sold out. I didn’t see anything else listed. Did I miss something? Did I go to the wrong site?

[@ClearOutSamskaras]

Gentlemen, I'm new to your work. There must be something I'm missing that everyone else knows but I'm going to ask anyway. How is this machine a stereo preamp? I see no source selector. It looks like a phono preamp to me if anything.

[@tubelab194]

@@ClearOutSamskaras the input selector switch is on the top right side between the two pairs of RCA inputs. This is the topology we use for all our control preamps. We'll be doing a more in-depth review of the circuit and build in a few weeks time, as well as sharing some of the secrets for why a small simple preamp sounds so good (hint: it's the tubes and short signal paths + a really good power supply design).

[@ClearOutSamskaras]

@@tubelab194 Thank you for your reply. I look forward to the explanations of how the simple and small design achieves outstanding sound quality.

[@gregmerten3832]

What is the other channel

[@tubelab194]

@@gregmerten3832 Mellow Tone Kits, we placed a link below the video.

[@matthewhilty4209]

Can you get brass screws to compliment the gold color ?

[@tubelab194]

@@matthewhilty4209 no, and even if we could they would quickly tarnish and require you to remove all the exterior fasteners (20 that are visible) and polish them up, roughly every 6 months, maybe a bit longer if you waxed them!