ThePog Posted January 10, 2023 Share Posted January 10, 2023 I got it into my stupid fucking head to build a guitar amp valve mini stack along the lines of this old tiny Marshal stack i once used which was awesome. It was a wee head with two channels and the first channel had been preamped into the second for mega valve gain. Obviously I aint paying for no fucking Marshall so i figured a couple of valve radios might do it or maybe an alix kit. If it is a radio does anyone have anything or know what would be best to look for? I am imagining that radios without transformers are probably a no go. What you reckon? 1 Quote Link to comment Share on other sites More sharing options...
smokin'joe Posted January 10, 2023 Share Posted January 10, 2023 so you want a cheap valve amp ?? may know of a couple of Holdens and Jansens, and you should have asked a week ago, as currently in kaikoura ! Quote Link to comment Share on other sites More sharing options...
Truenotch Posted January 10, 2023 Share Posted January 10, 2023 Haha, I actually own an old valve radio and was planning to do this a long time ago. Still pretty keen to do it one day, do you have a method in mind, or going to figure it out as you go? Quote Link to comment Share on other sites More sharing options...
h4nd Posted January 10, 2023 Share Posted January 10, 2023 12 hours ago, ThePog said: guitar amp valve mini stack along the lines of this old tiny Marshal stack i once used which was awesome. It was a wee head with two channels and the first channel had been preamped into the second for mega valve gain. I ah, have a set of photocopies of Marshall etc circuits (hand drawn - no less). May include marshall valve amp circuits. Want me to scan some up? Shit, come to think of it, I prolly have some valve transformers and caps lying around in the junk bins. One channel may have used an old TV knob, which went to 11 3 Quote Link to comment Share on other sites More sharing options...
ThePog Posted January 10, 2023 Author Share Posted January 10, 2023 13 hours ago, smokin'joe said: so you want a cheap valve amp ?? may know of a couple of Holdens and Jansens, and you should have asked a week ago, as currently in kaikoura ! Well kindof but I want it pretty small. I think the one I used was like this; https://www.kbbmusic.co.nz/marshall-dsl20h-dual-super-lead-20w-valve-amplifier-head-w-reverb-pedl-90012-2-btn-f-switch But it was real oldschool, no effects and two seperate 20w channels, no light up power switches or anything. plus it was done in a cream fabric and had a couple of matching single 10" speaker cabinets. It was amazing. Recreating that is the aim. 13 hours ago, Truenotch said: Haha, I actually own an old valve radio and was planning to do this a long time ago. Still pretty keen to do it one day, do you have a method in mind, or going to figure it out as you go? Bludgeon my way through it without really knowing what the fuck i am doing I imagine. 1 hour ago, h4nd said: I ah, have a set of photocopies of Marshall etc circuits (hand drawn - no less). May include marshall valve amp circuits. Want me to scan some up? Shit, come to think of it, I prolly have some valve transformers and caps lying around in the junk bins. One channel may have used an old TV knob, which went to 11 The schematics could be worth it, there are valve amp kits on AliX that i could adapt maybe? Even router my own pcb's if i get excited. 2 Quote Link to comment Share on other sites More sharing options...
h4nd Posted January 10, 2023 Share Posted January 10, 2023 Cool, have a go. I see this one has an LED under the tube, for extra heater glow? (LoL) https://www.aliexpress.com/item/1005005125142338.html I don't see audio transformers in the kits I've glanced at, and I suspect a lot of the sound you liked is in the big valve power stage with the 300V to 8ohm iron output transformer, but, have at! Quote Link to comment Share on other sites More sharing options...
h4nd Posted January 10, 2023 Share Posted January 10, 2023 Also, Public Service Announcement: High voltage dc power supplies for valve amps are notably dangerous. Use safe working practices like clear easy off switches, properly grounded chassis, isolation transformer and having someone in the workshop when fecking with the nasty bits. 5 Quote Link to comment Share on other sites More sharing options...
ThePog Posted January 10, 2023 Author Share Posted January 10, 2023 15 minutes ago, h4nd said: Cool, have a go. I see this one has an LED under the tube, for extra heater glow? (LoL) https://www.aliexpress.com/item/1005005125142338.html I don't see audio transformers in the kits I've glanced at, and I suspect a lot of the sound you liked is in the big valve power stage with the 300V to 8ohm iron output transformer, but, have at! Do you reckon those amps work without the valve even plugged in? Wouldn't surprise me. As you suspect/know i have no idea what to do irl. I suspect if i could look at schematics it would give me a better idea if its worth going down thd full diy track, which would probably be the most satisfying Also; Safety notice received und understood.... 1 Quote Link to comment Share on other sites More sharing options...
ThePog Posted January 10, 2023 Author Share Posted January 10, 2023 US $57.69 8%OFF | Nobsound Home Audio Tube Amplifiers DIY Kit 6Z4 + 6N2 + 6P1 Stainless Steel Shell Power Output 2 * 4W AC110V / 220V https://a.aliexpress.com/_mtSQ4tG Quote Link to comment Share on other sites More sharing options...
h4nd Posted January 11, 2023 Share Posted January 11, 2023 Oh LoL: Should really be tagging @kempy and @Ned in here, they have accumulated wisdoms (and parts stashes) 1 Quote Link to comment Share on other sites More sharing options...
h4nd Posted January 11, 2023 Share Posted January 11, 2023 https://www.aliexpress.com/item/4001066299107.html Quote Link to comment Share on other sites More sharing options...
ThePog Posted January 11, 2023 Author Share Posted January 11, 2023 That looks good actually. However this one has sound that is charming and aura; https://www.aliexpress.com/item/4001057048556.html Quote Link to comment Share on other sites More sharing options...
h4nd Posted January 11, 2023 Share Posted January 11, 2023 That is indeed charming looking, but is only the rectifier (not an amplifier) Quote Link to comment Share on other sites More sharing options...
Nominal Posted January 11, 2023 Share Posted January 11, 2023 4 minutes ago, h4nd said: That is indeed charming looking, but is only the rectifier (not an amplifier) What even is this "The 6H2 rectifier tube belongs to the vacuum space charge movement mode. It moves in the crystal grain relative to the semiconductor current, and has a time lag effect on the front and back drops of the audio signal waveform. In addition, under the vacuum condition of the bile duct, the charge cannot have solid impurities Particle collision. The original ecological rectification is beneficial to audio transmission." Quote Link to comment Share on other sites More sharing options...
ThePog Posted January 11, 2023 Author Share Posted January 11, 2023 Dude is on a whole other level to us plebs. Quote Link to comment Share on other sites More sharing options...
Thousand Dollar Supercar Posted January 11, 2023 Share Posted January 11, 2023 Quote "Especially for small size, those who are interested can compare it by themselves to get pleasure." In the video which Hand posted, the narrator literally thanks Barry at Amp Maker around 16:55. I imagine that any valve amp which has a 12VDC input instead of a big AC transformer must be using a step-up voltage converter to produce the high voltage which the valves require. This seems to be what my nixie and magic eye tube kits do. It goes without saying that big transformers are more hipster. My brother once had the valve radio from our bach house modified to take an auxiliary input. The idea was that you could play music from an iPod etc through the radio's amp instead of being limited to whatever stations the radio could still receive on AM. If that modification was done in such a way that a line-level signal was required, I guess you could still play a guitar through it by using something like an overdrive pedal to act as the guitar preamp? I could ask my brother where he had the modification done to the radio, but it was years ago - the Barry who did it might not be in business any more. 1 1 Quote Link to comment Share on other sites More sharing options...
h4nd Posted January 11, 2023 Share Posted January 11, 2023 ^yes, re power supply, but you still need to get from 600V at 0.1A down to 22V ac at 3A for the speaker, so prob still need the audio output transistor (unless you're rocking electrostatic speakers, but they're very rare). ^Volume control mod, yes, genius! Quote Link to comment Share on other sites More sharing options...
ThePog Posted January 16, 2023 Author Share Posted January 16, 2023 I have been obsessively delving into valve amp stuff and after trawling TM and finding this I decided to save myself a shitload of time and money; 5 Quote Link to comment Share on other sites More sharing options...
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