Recommend a *specific Brand / Model* 120V to 100V Step Down Transformer

Discussion in 'Audio Hardware' started by TheVinylAddict, Nov 6, 2017.

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  1. TheVinylAddict

    TheVinylAddict Look what I found Thread Starter

    Location:
    AZ
    Hang on... that's a great point Jim - in fact when I was checking continuity on my outlet a couple of months ago, I recall that it as reading something like 128V? Is that possible? I am definitely going to check now....

    115V to 128V is the same gap as 100V to 115V, so it is not trivial. Thanks for bringing that up, good advice.

    EDIT - meant to add too that yes, our mains are 120V
     
  2. harby

    harby Forum Resident

    Location:
    Portland, OR, USA
    Last edited: Nov 10, 2017
  3. TheVinylAddict

    TheVinylAddict Look what I found Thread Starter

    Location:
    AZ
    Yes, I am very aware of this option. I wouldn't spend $2000 on a TT and miss this fact!! :).

    I will be looking for a YOP (the Yamaha accessory that gives the 24V - there are knock offs, and I will consider only ones that get good reviews - there may be a couple). on the side for the right price, but not required.

    Even with this, it still needs to be stepped down to 100V, does not change the need there!
     
  4. harby

    harby Forum Resident

    Location:
    Portland, OR, USA
    Not if it is cloned with a transformer wound for 120V instead of 100V.
     
  5. TheVinylAddict

    TheVinylAddict Look what I found Thread Starter

    Location:
    AZ
    OK, an update. Thanks to Jim's pointing out the voltage gap, I checked my voltage, and I called the company. I am around 125V at home.

    They also make a model that does 125V to 100V AJD25-1800 Tru-Watts™ 125 Volts to 100 Volts Step Down Transformer - Use 100-Volt Japanese Electrical Devices in USA/Canada – AJD25-1800 CTOC but it it was overkill at 1800 watts and too expensive at $369.

    The owner said they were making a newer model that was in the 250W range, but it wont' be available in the short term.

    According to his calculations though, if I used his 115V to 100V model 300 Tru-Watts™ Step Up Transformer Converter - Use 220 Volts appliances in 110 Volts countries - AU-300RF , in my situation it would still step me down to about 107v or 108V... which in his humble opinion for a DD Japanese TT is acceptable.

    I am still in the research mode now.... it's a great product, but I now would prefer something similar that was 125V.... but it may not be required.
     
  6. TheVinylAddict

    TheVinylAddict Look what I found Thread Starter

    Location:
    AZ
    Link?

    I would rather get the Yamaha YOP to transform, and then step down.... unless you can point me to something better that is wound that way.
     
  7. jea48

    jea48 Forum Resident

    Location:
    Midwest, USA
    128V is considered very high for an RMS voltage measurement. If your mains voltage is 128V you would be replacing a lot of incandescent light bulbs due them burning out often. This is if they are 120V and not 130V bulbs.

    It might just be the multimeter you are using. You need to find out though.

    Do you notice some light bulbs in your home, of the same wattage, are brighter in one area of the your home than other areas? Or you seem to be replacing light bulbs more often in the same light fixtures than others? If yes that could indicate somewhere from the utility power transformer to your main electrical panel the electrical service entrance neutral is not making a good solid tight non corroded connection.

    I would suggest you check voltages at various outlet locations in your house.

    If you are getting the high 128V only on the branch circuit your audio equipment is plugged into and another branch that is lower than say 120V that could indicate the 2 circuits are a multi wire branch branch circuit. The 2 circuit share a common neutral conductor. The common neutral wire could have a loose and or corroded connection.
     
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  8. harby

    harby Forum Resident

    Location:
    Portland, OR, USA
    The last page of the thread I posted has someone that made a replacement power supply ("I just made a few power supplies for those who have such turntable. Several copies are also outside of Russia - in Croatia, the United Arab Emirates and next to you in New Zealand.") - countries mentioned use 220V, and he may just use a transformer in the design appropriate for the destination.

    The transformer in this PS converts 100V line voltage into something like ~28VAC, a voltage that drops under load from the rectifier and in-series resistors in the design (and also spikes from brownouts and impulses from other appliances on AC power).

    A transformer is a simple ratio of windings. For example a 4:1 winding transformer would turn 100VAC into 25VAC, but 120V into 30VAC.

    If one had the YOP in-hand and could measure the transformer output voltage (either powered by 100V or 120V, just do the math), a replacement transformer could be specified to modify a YOP to 120V.

    Alternately, a modern regulated SMPS before the "sense" transistors in the circuit could put out the 24V, but +/- 0.01V with no 60hz ripple, regardless of the input voltage or load.

    BTW, a variac, as mentioned before, is just a special type of non-isolated transformer that lets you adjust how many windings are in the output, to adjust this voltage ratio.
     
    Last edited: Nov 10, 2017
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  9. TheVinylAddict

    TheVinylAddict Look what I found Thread Starter

    Location:
    AZ
    Harby, Jim - you guys are awesome....

    I have learned a ton on this thread, and I bet anyone who pulls this out of the archives down the road will too... this is one area I am not strong in, but thanks to this thread I just got better.
     
  10. jea48

    jea48 Forum Resident

    Location:
    Midwest, USA

    Even 125V is considered high. If your mains voltage is 125V you must go through a lot of 120V light bulbs. Is that the case? If not then I would say the mains voltage is not 125V, or even 124V.

    What brand is your multimeter? If it is some really cheapo unknown brand you might want to buy another one. You can buy a descent digital multimeter for around $30 to $40.

    If you buy another meter and it reads 125V as well, I would call the power company and ask them if they would, please, come out and check the voltage.
     
  11. TheVinylAddict

    TheVinylAddict Look what I found Thread Starter

    Location:
    AZ
    Jim - I have many multimeters - I am going to get my Fluke out of my mechanics box in my garage. I used a cheapo $20 on Amazon.

    I will report back. You may be right.
     
  12. TheVinylAddict

    TheVinylAddict Look what I found Thread Starter

    Location:
    AZ
    Ha ha Jim, you were dead nuts correct - I went out and got my Fluke out of my mechanics box (a nice one I paid $250 for (or more) because I work on my own cars) ---------- and guess what, it read 120.4V. Poifect.

    All good in the hood, thanks homeslice.
     
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  13. TheVinylAddict

    TheVinylAddict Look what I found Thread Starter

    Location:
    AZ
    For others that might read this thread down the road - this has been highly recommended by two people who both use it, and have a number of Japanese market turntables.

    300 Tru-Watts™ Step Up Transformer Converter - Use 220 Volts appliances in 110 Volts countries - AU-300RF

    One of them uses it with 115V rated outlet, the other with 120V related - no real issues to right home about with using this on 120V, because the net affect is it deliver something like 103V to the Japanese TT, and that is within an acceptable margin. A contact out of Japan (who sells TT) says it is not uncommon in Japan to see a plus / minus of 3V in their homes, so don't worry. 103V is much better than 120V.

    I am going to buy this one... thanks all for your responses.
     
  14. jea48

    jea48 Forum Resident

    Location:
    Midwest, USA

    Don't you mean this one from your post #24?

    300 Tru-Watts™ 115 Volts to 100 Volts Step Down Transformer - Use 100-Volt Japanese Electrical Devices in USA/Canada – AJD-300
     
  15. TheVinylAddict

    TheVinylAddict Look what I found Thread Starter

    Location:
    AZ
  16. 808_state

    808_state ヤマハで再生中

    Owner of both GT-2000 and GT-2000L. The simple short term solution is a Kashimura step down:

    https://www.amazon.com/gp/aw/d/B013...=0HR78DEN6G8MVDSRVDB5&dpPl=1&dpID=61JfHSv0upL

    At 3x the wattage you're covered. It's plenty quiet, I've used mine with an HA-1 phono step up.

    The long game is an aftermarket YOP-1 from Yahoo jp auction. Some of them are specifically made to run on 120v to give 24 volt output and the US to JPN step down becomes moot. There are pages and pages on the AK forum about how this improves the sound and I can confirm it's the truth. Congratulations on a great table. Once you get used to using it you'll wonder why so many new tables, even expensive ones have such a thin and weak plinth.

    Save $100 to put toward a YOP-1!
     
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  17. Cockroach

    Cockroach Well-Known Member

    Location:
    Visalia, CA
    Sounds like your other meter may not be a true-RMS meter. I know the Flukes read true RMS.
     
  18. TheVinylAddict

    TheVinylAddict Look what I found Thread Starter

    Location:
    AZ
    Yes, already shopping the YOP-1, problem is they are not that easy to find, and you are going to have to pay up.... I definitely want one, and already did the research. Thanks for the testimonial.

    I just watched one go through Yahoo Auctions, but did not see what it closed at price-wise. I know after shipping, consumption tax, paypal fee (buyer pays on YA, not seller) it was getting close to $500. I am not 100% confident in Yahoo Auctions, it is tough for me to support a business model that chargers the BUYER for all the fees, an auction where you CAN'T communicate and ask the seller questions, and one where your final bid / estimate is just a guideline and typically ends up with more fees after the sale.... YMMV but I am not alone there.

    Back to the YOP-1 - I see a few "clones" out there, some say are good, but just not sure. I will keep looking, but will probably have HiFiDo do the leg work and buy from them.... they are still the best option IMHO... that is unless you know someone in Japan and they can do the leg work for you.
     
  19. TheVinylAddict

    TheVinylAddict Look what I found Thread Starter

    Location:
    AZ
    Thanks for the recommendation, but I am going to turn the tables on you - first, I am not looking for a "short term solution" I am looking for a solution. Why are you calling this "short term?" What did you decide on long term is what I would be more interested in hearing!

    Then, recall that I would like one that can handle more than one table, and two tables pushing 30W (without YOP-1, with it the GT-2000 drops to 7w I believe) I would not trust in this 35W model. Plus - where is that made? The ad is Japanese, but was that made in Japan? China? Please advise, the link on Amazon does not specify (typical Amazon).

    Finally, I am surprised you are trusting your high dollar GT-2000's to that, and not paying up a little more for something NOT made out of plastic, and with more elaboration of the internals, build quality etc.

    I am going to stick with my choice for now. There are not as many 120V -> 100V step downs out there as there are 120 V / 240V models, and I am going to err on the side of higher quality. If I were buying a $200 TT, I might take your rec, but at 10x that price, I want peace of mind. Recall I mentioned that two very reliable people who own many of the high dollar Japanese TT's recommended the one I am buying, and SPECIFICALLY more than once told me to avoid these cheaper models.

    I don't mind spending up for quality given the TT I am buying. Thanks again for the recommendation, and I welcome any rebuttal or defense of your choice, I am challenging you! I am not an expert in these devices (I am finding out that not many are).
     
  20. 808_state

    808_state ヤマハで再生中

    Mine is a clone, runs on 120v and works flawlessly. The originals are overpriced and stuck at 100v. The originals go for $500 usd and the clones go for $250-$300 usd (if you are patient).
     
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  21. TheVinylAddict

    TheVinylAddict Look what I found Thread Starter

    Location:
    AZ
    Link to the one you own, if you don't mind? I see a number clones, I think I am looking at a good one... but just curious what you bought.
     
  22. 808_state

    808_state ヤマハで再生中

    Well my point was that if the Kashimura is quiet enough to work with a phono lomc step up transformer, it should work just fine to allow you use the GT while you research the YOP-1. But not using the internal power supply of the GT and instead using an outboard one is always the best solution.
     
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  23. 808_state

    808_state ヤマハで再生中

  24. TheVinylAddict

    TheVinylAddict Look what I found Thread Starter

    Location:
    AZ
    Yes, that is EXACTLY the other one I have been shopping... seen it many times, and the fact you have it is one big step in my maybe buying it sooner than later. Here are the two I am watching on Yahoo Auctions (English version):
    YOP-1 interchangeable power supply YAMAHA GT-2000X/L series for high class machine Version,Ⅱ overseas specification AC115-240V: Real Yahoo auction salling
    YAMAHA GT2000 X/L exclusive use power supply YOP-1 interchangeable Premium POWER SUPPLY Ⅲ domestic specification : Real Yahoo auction salling

    Ebay : Yamaha GT-2000 YOP-1 Compatible Power Supply | eBay

    Do you know anything about the other model I have shown? I appreciate any thoughts you have. Plus, I will still need a step down with the YOP-1, it is a 100V device, right?

    My GT-2000L is still being prepped for shipping, so I can afford to do a little more research on the Step Down.

    Thank you for your response, they have been VERY helpful!
     
  25. 808_state

    808_state ヤマハで再生中

    No problem man...the second one is a domestic or for Japan model so the first one is the one you want. It's the same guy selling them and he changes his user id from time to time. He tried to raise the price to $400-$500 usd for a while and quickly figured out they don't sell at that price. A domestic clone or original will still require a step down so that's why the first is the best option because it reduces the number of steps to power the player.
     
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