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@@audiorick841 below each of these "How To Solder" videos is a list of tools and materials, including our preferred solder. When we have time, I'll film a short video on solder types as per your suggestion. Cheers Jim

Hi Fred, thanks for the interest in the kit. We appreciate suggestions on how to improve it, and encourage people that want to tinker to modify things if they want to. But the one thing we suggest doing first is to build the kit as designed. We put hundreds of hours of work into designing, testing, building, and iterating each one of our kits. Many suggestions including most of yours are ones that we've already tested and found to be unnecessary thanks to our careful design work. Cheers! Charles

@@BelgianGadnuk finding suppliers for the hundreds of quality parts we need for each Kit, means shopping the World. A lot of our transformers come in via Digikey, but some like the Zero Zone come in via AliExpress. Both offer excellent products and service.

@@joemartin6439 yes and no, all of our Kit amps run in Pure Class A (no feedback) and both our monoblocks are Triode strapped Beam Powered Tetrodes, so they operate as SET (single ended triodes). The problem with running a true Triode in Class A, is power. In order to supply enough power to satisfy our customers you really don't have any (none, nil, zilch) affordable vintage power tube options. But figure out how to operate a Tetrode as a Triode and now you have some amazing sounding vintage power tubes to work with, including the GU50 and 6P7S.

@@adrielrowley The 1000uf 50v electrolytic capacitor across the smps dc input is a filter, it shunts anything above dc to ground, making a very low noise dc filament supply.

Thank you Jim for the lesson, it is appreciated. Cheers, Adriel

Totally agree because that’s what I do.

@@auggysimcity hmmm the Universal Preamp does utilize a linear power supply, as do all of our Kits. If you go to the Store information download section you can look at the actual power supply schematic. Now in many of our Kit Preamps we use small SMPS (switch mode power supply) to supply dc to the filaments and this provides a very low noise supply, for very little extra dollars.

@@NicoRas-e9m Speculation is something you do when choosing a stock to buy, and doesn't describe our work or reviews. Both of us work professionally in audio and we spend a significant amount of time critically listening to gear we've designed. We back up our subjective listening tests with complete schematics, specifications, sound clips and very detailed sweeps. Not convinced that you can build your own audiophile grade preamp? Just drop in on any Kit we sell and read the reviews.

@@PINKFL0YD-s2h Haha obviously not a Jazz fan! "In a mellow tone" is something great band leaders like Dizzy Gillespie would call out when they want to chill down the music, a lot like the sound of Pink Floyd. And talking about The Floyd, our tube gear all sounds amazing when we're playing our original first UK quad of DSOTM.

@@airgead5391 yes there are some truly amazing NOS vintage 12SL7's still available. In our listening tests the Sylvania's rule! They have a warm/rich sound and excellent detail. And yes they do have more 2nd harmonic distortion, but in a phono preamp that's exactly what you want.

@@mellowtoneamps4932 I have a few of Tung Sol dark glass NOS: they sound totally awesome.

@@rasmus.O.B correct, the build of the CF stage in your Universal Phono is identical. Now the operation of the 6N6P is going to be different, with a slightly higher current draw, but in our experience the CF stage benefits from higher current and that discovery lead us to trying a high current tube like the 6N6P. What you'll probably notice right away is a nice improvement in the bass frequencies and even better clarity. At this level of sonic performance, we always thought the most we could achieve with a circuit revision was a very small improvement - but clearly we were wrong! The 6N6P was really only made in quantity by one Soviet factory (NEVZ). I think with the rare early Foton type and the -I type we have a total of only 3-4 options. Not a very interesting video! The good news is the commonly available NEVZ 6N6P sounds amazing in every circuit we've tried it.

@@mellowtoneamps4932 Thanks! appreciate all the content you guys provide!

Perfect, I was planning on building a phono pre amp as my next project! Hope to get to test this soon!

@@davegrant9179 thanks! You are probably referring to Mr. Warthog, he's Geordie's fav playmate. Geordie is my mum's Yorkshire terrier.

@@mfr58 Thanks! As audiophiles ourselves, we work hard at creating great sounding and affordable audio gear.

Our favourite headphones to use are the 150 Ohm Sennheiser HD660S, but the budget 80 Ohm Beyerdynamic DT770 Pro also sound great.

We have not, but we have developed a passive stepped attenuator kit that fits on the classic line chassis and provides excellent performance.

@@Kulpa-Systems it will be available for Test Builder's this Fall, then once it clears them it will go to the general public. To see the Kits currently available I've put a Link below the video.

@@NosEL34 one of the design directives to Charles was to leave some extra space for larger coupling caps. Unfortunately unless we enlarge the chassis there just wasn't any available to spare. With a much more affordable design, keeping the cost down was important. But interestingly the Vishay caps that I chose sound amazing and they sweep very wide band, something like 10hz to 20khz -1db with most of the response dead flat. Personally I'd recommend building with the Vishays and listen to them before even thinking about trying something else. We also use the Vishays in the Universal Phono Pre, and in that circuit they also sweep and sound way better than you'd expect.

@@matthewhilty4209 we'll always have our "Classic" lineup, for some larger amps, you really need the strength of that 3/16" thick top plate. But the work (time, inventory and money) to release 2 different types of chassis for the same Kit probably precludes offering them for the odd customer who wants one. Creating a more affordable line introduces it's own set of problems!

I would choose the smaller black chassis as well if it was available. I do own one of their Cherry plinth enclosures..they are very nice looking in person.

@@garyvitrano8362 good question, IF your volume pot is a passive device like a blue alps or 99% of all pot ever made (till recently when manufacturers started switching to chips) then whatever the impedance of the pot is, that's the input impedance of the amp. So in your case 100k ohm, even when the pot is fully open. You can actually measure this, with the amp off, use an old rca patch cord, strip back one end to a centre conductor and ground shield, connect both to a volt/ohmmeter, switch to ohm function and Bob's Your Uncle.

www.valvesnmore@protonmail.com look on the top bar (centre).

@@HoomanR17 unfortunately it's not practical to design for 3 inputs, at least not the low noise circuit topology I like to use. When we design a new Kit we have the sonic performance as a priority, then the features that 90% of users will need, then aesthetics.

@@mellowtoneamps4932 Thanks for your explanation. I understand the criteria for your design. Correct me if I'm wrong, but isn't the input # just the difference between going from a DPDT switch to a TPDT switch, or is it the case that the brand/quality switch that you use doesn't come in that flavor?

@@HoomanR17 correct the switch type we use is limited to DPDT and where would you even put a 3rd pair of RCA jacks? We have a multitude of source signals and whenever we run out of inputs we just swap one out. Otherwise we'd need a dozen inputs, which would basically be a patch bay. And that's not something I'd want even in our main critical/test system - though the idea has merit!

@@davidkclayton glad you asked! Our noise floor is -53.8 dBr, which is pretty good for a very high gain tube circuit and well below the noise floor of a high quality stylus running in the groove. We publish complete specifications for all of our Kit Amps. Just go into the store to top right "Information" and you'll find everything we publish. Note that no one tests with an open rca input, it wouldn't reflect anything like a true operating circuit. Much our data is derived from a closed loop sweep. Any questions can be sent through the store contact page. www.valvesnmore@protonmail.com

@@mellowtoneamps4932 Hey cool thanks for the Info. This is good news for me I've been working on modifying the common EAR 834 phono preamp circuit board design, reducing the size and the noise floor. I think with the next reiteration of boards I can get it below -70DB I'm at about -65 right now. I don't mean to brag but if anyone's interested, they could visit my channel to see the progress. Also, I will open source all of this

@@davidkclayton it's not considered good etiquette to piggy back on someone else's Channel or the comments section.

@@mellowtoneamps4932 well I'm sorry didn't mean to get you all bent out of shape. That's how I found your Channel. Anyways I thought the community was a little tighter than that . I don't mean to compete with you. Please accept my apologies.

@@davidkclayton Haha no worries, it takes a lot more than a wee faux pas to get me bent out of shape!

No none if the connectors are of good quality and you take your time to ensure a good installation, which btw is no different than making a proper solder connection. What most people just starting out don't realize, is that the vast majority of electrical connections are made mechanically, especially very high voltage ones, but wee ones as well. Same goes for patch cords, they're basically friction fit contacts, same goes for IEC plugs and all of your house mains. At least with a mechanical connection you are applying torque to the connection, which ensures good contact.

Correct.

Good point, we use whatever test leads are handy (we have dozens of them), but not a good way to teach beginners!