I'm a fan of the NOS GE JAN tubes in general. They are very robust with low microphonics and outlast just about everything else. They also sound VERY good. I'm using some ex video tubes in my Spud.

In the Rega arms I've seen, the ground is connected to the shield of the left channel. Instructions to amend this grounding schema is readily available by searching online. However, there is benefit in rewiring these arms as well, as the tonearm wiring is not the best quality anyway. In that case, wire it so as to to incorporate a separate ground wire that you can plug into the ground terminal of your phono amp or amplifier if you have one with an integrated phono stage. There are vendors that sell the complete wiring kits for Rega arms, so check those out.

After posting my earlier comment on turntable grounding, I realised I had not mentioned anything about direct drive turntables. (I only restore belt drive types) Early on, I did notice that direct drive turntables were more prone to hum. In some cases, the hum increased as the cartridge traversed toward the centre of the record. This type of hum is induced from the motor itself and is very difficult to cure. Some types of cartridge are more prone than others. I suspect that newer direct drives are somewhat better in this respect than the older ones that I was repairing at the time. (Better platter design to shield the motor) It is one of the reasons that I prefer belt drive tables as the motor is further away from the cartridge, but in saying that, I have repaired some belt drive turntables that also exhibited increasing hum as the cartridge traversed the record toward the centre, and hence close to the motor. Early Regas were notorious and I never heard one that did not hum at least a little bit. They all seem to rumble too, but that is a different issue inherent in breadboard designs. I think Rega has addressed the issue by changing the motor, I'm not sure as I haven't seen any late models in my shop. But getting back to direct drive TT hum issues, you can try different cartridges as some are more prone to picking up hum than others. I think there could also be a case for installing an IEC socket with RF/EMI filter, or some other type of external filter. It can't hurt anyway. Adding a ferrite to the cord may also help and is cheap. Other possibilities to look at are the internal shielding of the tonearm wires and the judicious use of aluminium foil where the wires exit the tonearm (keeping it well away from mains voltages of course!) I have never tried this, but it may help in chronic cases. If people are into modding cartridges by installing them into new bodies, perhaps a body made from aluminium might shield the cartridge better? A lot of cartridges are made with plastic bodies that offer little shielding. Try one with a metal body and see if that helps. If it does, then you're on the right track. As audiophiles, we all hate hum!

Both my turntables are vintage, Thorens TD124 and TD125. Restoring highly regarded Euro or American turntables is what I do. I've restored a about 100 by now. In all cases, I now convert from the existing power twin cord to a twin cord with ground, and change the grounding schema to ground the cartridge directly through the ground pin. And dispense with a separate ground cord that attaches to to the phono stage. One local customer still had a slight bit of hum, but because I did not not in testing, I concluded that his hum issue was EMI related. Where possible I always change the power cord to an IEC so that the customer can have an option to use their own power cord, so I changed his IEC to one with an EMI filter. This sorted out his hum issue. I've also had success with building a power cord with a drain. A local electrical company supplies a very good screened cable with a drain wire so that's what I use. I don't pretend to fully understand how these things work, but they do. In cases where a client uses an MC cartridge, I always recommend the use of a good SUT between the turntable and RIAA phonostage. This always seems to sound better than connecting to the MC stage of the preamp which is just a bunch of unwanted electronics in the signal path and there is less hum. I'm convinced that the induced signal is the way to go over the MC stage, if only for hum mitigation, but there are other benefits as well in terms of sound of course.

Mine is a single box with a toroidal transformer that I built myself. Also no hum, but it doesn't have a pot. A pot is a nice feature I think. I did play around with various caps and tubes. I ended up putting 12at7s in v1 and v2 to lower the output a bit as it seemed a bit over driven with 12ax7s. But my friends separated version with a pot seems to solve that issue. He's running some nice vintage GE 12ax7s out of an heirloom guitar amp and it sounds absolutely beautiful.

A friend has just purchased a completely built version of the EAR834, a twin box version where the power supply is in a separate aluminium case. Very nice it was too, with a genuine Alps Blue potentiometer. It had the torroidal transformer. I've just finished upgrading the usual caps. Absolute NO HUM and sounds stunning! Result!

Well this is interesting. From my research, there are indeed different iterations of the transformers depending on the manufacturer. Yes, it appears there may be more than one or two! The A10 and A12 can appear with either Japanese or Chinese transformers. The trouble is that the potting means it is impossible to know what we are buying. There are at least two sellers that emphatically promote their Japanese made transformer versions and claim 50% more headroom from their 200w power transformer. They also state OPT at 15w.

It's the same kit as mine. Have you tried different tubes? For example swapping the first two with 12au7? Also, try swapping cables.

I'm wondering if the wooden box might be an issue resulting in hum. A metal case might be better?

For the price, the Psvane (pronounced "pavane") sounds excellent and is very reliable.

It's not an amplifier that would interest me, but it probably sounds very good. All the info is there for you to make a decision!

Description Tube power amplifier DIY handmade. Spare Tubes New available. Construction drawings and description available. This amplifier was made by a hobby builder and technician first class. I'm switching to monoblocks made by the same builder. All info except about the technique via marketplace. I only respond to serious interest. Payment by bank transfer or cash. Not a tap on apps and will not be sent for reasons you also know, weight and fragility. EL130 Power Amplifier DIY Description: The amplifier is equipped with 4 pieces of E130L power tubes that are parallel 2 by 2. These tubes are in class A at a supply voltage of approximately 170V. The power tubes are connected to a special stereo output transformer. This actually consists of 2 single ended transformers, but they are wound on the same core. Each channel also has a single E80F as a steerer tube. The steering tubes are controlled from a filter print. The filter ensures that the low tones of both the left and right channels are combined and sent to both control tubes. The mid and high tones of each channel are sent only to the corresponding channel. For the low tones, however, the amplifier functions as a mono bass amplifier, with the transformer in fact acting as a balance transformer. For the middle and high tones as a stereo amplifier, with the transformer in fact as 2 single ended transformers. The power supply consists of 2 toroidal transformers for the high voltage and 2 toroidal transformers for the filament voltage of the power tubes. The filaments of the control tubes are supplied with direct current and form part of the cathode resistors of the power tubes. The amplifier supplies a maximum of 20W per channel for the middle and high signal. For the bass, the amplifier delivers a maximum of 2x25W (50W mono). The bandwidth (-3dB) runs from 20Hz to 50kHz. The distortion is <0.5% anywhere between 30Hz and 20kHz. The outputs of the amplifier are switched on with a delay to block start-up sounds.

Clearly based on the E130L pentode. I think it's either a kit or a home build by somebody very knowledgeable and capable. I don't think I've ever seen a commercially made E130L amp. Likely the seller doesn't have a clue about it, maybe a deceased estate sale, who knows. If you take it on, you may have a whole lot of sorting to do. But I bet it could be a very worthwhile project for somebody.

Not necessarily. It's well known that they change components based on shortages, what they can get or have on hand. I have been down these rabbit holes with some other Sino brands. Electronics built during the height of China's Covid era and lockdowns are a little suspect to put it mildly.

Hi Danny, it's looking very good! It will need more than a couple of hours of running time to be at it's best as you well know, so that is encouraging. Is it quiet? Did you make the chassis or were you able to buy it from somewhere? Also I noticed that the schematic was revised quite recently, ie. 2021, so I wonder what was changed as the Zen has been around for a long time. Also, did you bother with the "Anniversary Mod"? It would be good to compare with and without. I didn't realise that the DIY version had external output transformers. Those things are huge! I think If I built one I might be encouraged to build it into a deeper chassis and have them tucked away, although external is fine visually if they can be pushed to the back and shielded somehow. I noticed that my Decware SE84UFO2.1 is still a long way off. I ordered a year ago and I see that they are only up to the July/August 2021 orders now. 😌 I hope the wait will have been worth it.

For the past couple of weeks I've been trying 3 different vintage tube types, cold war era. The first are RCA JAN 6CL6 (Joint Airforce Navy) and the second are RCA FAA 6CL6 (Federal Aviation Authority). Both are excellent, and just as good as the supplied GE 6CL6. I suspect the RCA JAN and FAA are the same tube and just marked differently. The 3rd type are NOS 1958 JRC 6CL6s (Johnson Radio Corporation) which were manufactured by RCA. These are slightly different sounding, I would say a tad warmer, with a silkiness about them. https://repository.duke.edu/dc/adaccess/R0295

Nice one Danny. The vent will help dissipate any heat faster than convection from the case, so is a great design improvement. I’m looking forward to your Zen kit build! I built a little 2Tb Rasberry Pi NAS. I don’t know why I waited so long to do this project, It’s brilliant. I just need to add another 2Tb for backups now.

Awesome! No doubt we'll hear about here when your build is underway. I've just bought a lot of 20 NOS 6CL6, so I think I'll also be set for many years. So in addition to the 12 GE JAN 6197s, I have 6 RCA FAA 6677s and 14 RCA JAN 6677s. The FAA variants should be interesting to compare directly with the JANs. I suspect they could be exactly the same tube, but not having the respective specs to compare, who knows. I believe the FAA stopped using these tubes in the late 90s. They were mainly used in aviation radar units, so my guess is they would be premium tubes.

Danny, it would be awesome if you could build yourself the Decware kit using pt2pt wiring. As for the production lag and getting help, I think it's Steve being paranoid about keeping it a small family affair with a few helpers. But I don't see anything wrong with getting some of the mundane stuff done by a bigger group of helpers if it speeds up production. It does come with downsides though as there are lots of hoops to jump through and extra expenses that come with employing staff. I've been a business owner myself, and it can be a headache for sure. Jerry did throw in the towel with the Spud a few years ago, and a few guys convinced him to keep it going. I'm glad he did! By the way, do you have access to tube testing where you live? I was wondering how well-matched these JAN 6CL6 tubes are. My guess is they would be pretty close, seeing as they were made for the military. It would be good to know.

I agree, they are probably the best bang for buck phono stages available. I have had others that are much more expensive, but haven't sounded as good. These kits really make for an easy build, as the boards are very good quality and well marked out. If I had to build another one, I would put the power supply section in a separate box. A friend of mine also built one, and he split his into separate sections and used a different transformer, a vertical EI-core type, and he had the hum issue. I just used the toroidal one that the seller supplied me. I'm wondering if the torroids are the way to go for these board type kits.