My DIY 6L6GC stereo tube amp project, part 5

[Kalkaekie]

Looking good !

[mitzvy]

A very nice amp you built there my friend. I'm currently restoring a Harman Kardon Citation V but I'm only 15-20% finished. Nice weather has me working on outside projects lately. Keep up the good work!

[HalimAmy]

Any of you here willing to do 1 tube amp comes with speaker between 1-5watt whcich comes with a footswith

for a crystal clear clean channel and for distortion channel ?

I,m from Singapore . willing to pay in whatever mode u prefer...

[MrDeamon1]

Nice work!

[metalguitar1011]

Aww man I thought you were gonna hook up a guitar and jam!

[Maxxarcade]

@metalguitar1011 A friend of mine is learning guitar, so that may happen in the near future!

[metalguitar1011]

@Maxxarcade sweet! what kinda tubes are in that puppy?

[Maxxarcade]

@metalguitar1011 JJ 6L6GC outputs, Westinghouse 6SN7GT drivers, and Sylvania 6SN7GT's in the preamp.

[metalguitar1011]

@Maxxarcade 6l6 are good tubes

[ashleycox432]

That sounds amazing....

[xdeadstarpsyclonx]

God i'd love one of these :') or maybe to make a tube pre

[teendude16]

S\he's a beaut.

[nondescriptcitizens]

Wait, you spend some serious time engineering custom amplifier so you could play mp3s through it? 

[Maxxarcade]

@nondescriptcitizens If you saw my other videos, you'd see that I'm primarily a vinyl collector :-)

[lazzer408]

Do you have the schematic posted anywhere?

[Maxxarcade]

@lazzer408 Nope, I built it a bit at a time. The power amp section is essentially the Harman Kardon HK250 with an upgraded power supply, and the Pre-amp is a modified version of a circuit from the RCA RC-30 tube manual.

[lazzer408]

@Maxxarcade I see. I'm working on building my tube amp. I have everything I need. Power/output xformers and 6L6GT outputs and a pile of 12AX7s but I can't find the schematic for the amp it all came from so I have to start from scratch.

[Maxxarcade]

@lazzer408 Do you know the model/brand of amp your parts came from?

[lazzer408]

Your a furry! haha

[Maxxarcade]

@lazzer408 Well, most of us are just nerds that work in the technical field. It's a good way to unwind once in a while :-)

[dnl5649]

i dont like the harsh trebel either, i like the warm clean tube sound

[oldshovelhead]

Very nice

[mudbone80]

How do MP3's sound through this rig? Do you think FLAC would sound better?

[Maxxarcade]

@mudbone80 I would say FLAC or Apple Lossless is the best. MP3's tend to have harsh treble and not much dynamic range. Though I'm used to the full sound of Vinyl :-)

It also depends on the music. If what you are listening to is already loud and compressed (like most newer rock music) then you might not notice a lot of difference between formats. For stuff like 80's music, Jazz, Blues, Classical, etc, I'd definitely use a lossless format.

[Deph11s]

this thing is freaking brilliant man!

[ekcopyephilips]

Love the colour of the chassis

[CassetteMaster]

That's fantastic!

[IronSpandex]

Wow, great build! Love the minimalist look too.

[Maxxarcade]

Thanks, I'm looking forward to finishing the project in the near future. Still have a couple covers to make, and install the bottom cover on the chassis.

[kimbalxyz]

What speakers so you plan to use with it ?

[Maxxarcade]

The ones I used in the video. They work great, just a bit too much for my camera microphone.

[cgillyard]

Your amp sounds great for DIY! Interesting color for a amp.

[theGodSeat]

sounds great man!

[dnl5649]

damn that sounds so good for homebrew i have a really old bogen challenger tube amp

[maynardcat]

I enjoyed all 5 of your videos showing the building of your tube amp from scratch, they were very interesting. Do you buy a schematic for a certain type of tube amp, like the 6L6 you just made, if so do they have schematics or plans for an EL34 , Kt88, or 6550 type tube amp, with different power ratings.

[Maxxarcade]

There are schematics all over if you know where to look. AudioKarma is a good place to get some, or just Google Tube Amp Schematics.

[geeflyboy]

In part 4 you had a humm. What was the cause? Thanks

[Maxxarcade]

Several things actually. Bad grounds/ground loops, unbalanced heater windings, and magnetic radiation from the unshielded power transformers. Everything has since been fixed except for the shielding, which I am waiting on still. They need to be custom made.

[PROUDPUPPY]

Where can I get the schematics for this amp.

[Maxxarcade]

There aren't any, for the most part. The main power amp was based on the Harman Kardon HK250, and the pre-amp circuit was from the RCA RC-30 tube manual. But I made some changes to both circuits when I built this amp, and I don't have the modifications on paper.

[Machinia]

Just wondering where do you get covers for your transformers? I've got an amp project I'm working on and the two main laminated transformers are causing havoc to the signal and output wires.

[Maxxarcade]

Usually you have to make them. Sometimes you can buy them with the transformers, but that's pretty rare.

[KT88seamp]

In my amps I always use a voltage regulator to supply a constant 6.3 volts DC to the filaments. Only problem is you need a transformer that has a 9 or 10 volt filament winding. There are companies that can wind these units for you.

[Maxxarcade]

I have some 8.4v transformers that might work for that, if they can supply enough current. Do you build your own regulator circuit, or use an IC?

[KT88seamp]

I used a LD1084V with an 8 volt transformer. For my 11 volt unit I use an LM350k. Both require substansial heatsinking. You will have to use one IC per channel, or a regular circuit that can supply 6 amps.

[KT88seamp]

You amp may still hum even with the cover on. The filaments on all the tubes look to be AC powered and hum leaks from the filament to the cathode. This is especially a problem with the preamp tubes.

[Maxxarcade]

That was part of the problem too. I was able to greatly reduce hum by adding 100 ohm resistors to ground from the filament lines. If it persists after I get the covers, I'll probably have to use a DC filament supply.

[KT88seamp]

Does that amp hum at all?

[Maxxarcade]

It still hums a bit, because the shields are not on the transformers yet.

[nandoGdog]

Now I see why you painted the chassis orange, it matches you turn table pre-amp. Sounds great I'd like to build something simpler just to get my feet wet, maybe one of those Altoids tin headphone amps.

[retrochad]

That sounds amazing! I can just imagine how the bass is hearing it live. I saw the picture of the blue glow in the tubes and I had wondered how the progress was coming on it. I think tube type amps really make digital signals sound better (really they make everything sound great but especially they can take some of the harsh character out of digital stuff)

[mkafirebird]

wow thats looking amazing and it sounds awsome.ive been wonrdering what type of camera you were useing?ive been looking for a replacment.

[sheps999]

You using Lossless audio files?

[Maxxarcade]

That was regular iTunes format. Normally I use vinyl.

[wilkes85]

That fucker sure sounds excellent!

[poopooGarret]

I would leave the front decal free, it looks amazing as is with the simple orange on black

Hey what was that awesome image on your desktop? Something commissioned? I don't recognize the signature on it ^^

[Maxxarcade]

Ya, I'll probably leave it plain. I think I would probably mess up the finish if I tried putting decals on. A logo of some sort would be fun though, if I could get a good artist to paint it.

I got the desktop picture on FA. I think it was Nanook123 that drew it for someone else.

[weasel2htm]

I can't wait to watch this video at home on my main computer hooked to my good speakers rather then on this laptop. Are you planning to connect one of your AM/FM tuners to this (Like the Nikko shown in one of your older videos), or do you not listen to the radio in there.

[Maxxarcade]

I'm not sure. I might get a Logitech Squeezebox to play internet radio, or use my old Pioneer tuner. That's one reason I put 4 inputs on this amp.

[digidude86]

NICE!!!!!!!!!!!

[bluenazz]

That's a beatiful little tube amp but playing digital music through it kind of defeats the purpose (:->

[Maxxarcade]

I'd have used my turntable or reel to reel, but WMG mutes everything I play!

[spatsbear2]

Sounds absolutely amazing here on my end... Just imagining how amazing it will sound in person :)

[AllAmericanFiveRadio]

Beautiful job!! What a nice project and it sounds great too. I think it is just terrific to see a project built from scratch. It takes knowledge, determination, and skill to complete a project this complex. You will get many hours of enjoyment from this amplifier. You'll also find that your ears will not fatigue because of the quality of the sound.

[Maxxarcade]

Thanks!  I'm planning on building some more once I have the time and money.

I think the next ones will have the preamp in a separate chassis though. Even with the 17x10x3 chassis, there was barely enough room for everything this amp uses.

[Vinylrecordsneverdie]

Wow, that homebrew amp really pumps for 28watts! The R2R and the TT goes perfect with a tube amp. Can't wait to see it finished.

[Maxxarcade]

Heh, the volume was barely up :-)

[Vinylrecordsneverdie]

I wonder how it would sound with Bose speaker, LOL!

[weasel2htm]

No Highs No Lows Must be Bose :P