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$110 Tube Hybrid Amp Group Buy - Page 2

post #16 of 280

Some answers about the voltage issue

doobooloo,

I asked a friend to take a look at these pictures to see if it would be easy to configure the power supply to 110v-120v (I'm technically challenged). Here's his first reply:

"In one of the photos showing the power transformer, you can see a label on the transformer. It appears to have two windings on one side and three windings, two of which are center-tapped, on the other side. Since the center-tapped windings would normally be on the secondary, then other two windings comprise the primary. A transformer with dual primary windings can normally be hooked up for two voltages. Doobooloo says it's designed for 220V, so the windings could be reconfigured to run at 110V. Since 120V is the North American standard, the amp's internal voltages may be about 10% too high, possibly pushing the limits of the regulators in the power supply. Unfortunately, they don't show a schematic for the power supply.

Reconfiguring the transformer for 110V operation may be a challenge in the assembled units if the transformer wires have been clipped short. If the transformer has lugs on it, it may be easy. It shouldn't be a problem if you buy the kit version.

Perhaps doobooloo can request that they be assembled for 110V and also could ask the manufacturer if the transformer has dual primary windings."

He then found a close-up picture of the power transformer from the website, and sent me this reply:

"Here's a photo where you can read the text on the transformer. It has dual 110V primary windings as I guessed. There's still the question of whether the wires are clipped off once they set the unit up for 220V"

http://student.zsu.edu.cn/~is00wy/HP...P100A_OE06.jpg

So please check to see if the seller can convert it to 110V or if the wires are long enough to reach the other side of the transformer, or if the transformer has lugs on it (I suppose that means wires are not hot-wired into the transformer, but somehow connected to the transformer by screws or lugs.)
post #17 of 280
Just wondering how good would this thing be with low-impedance headphones, could this be useful with a pair of Grados? Eg., how would it compare to an RA-1?
post #18 of 280
please put me down for one if a 110v version is available. Thanks
post #19 of 280
I am definitly interested if they can do 110V version (for USA)!!!
And Paypal is no problems - thanks
post #20 of 280
More info at http://www5.head-fi.org/forums/showt...threadid=17448

That is the "upgraded" SonicAdventure Reality version.

regards,
halcyon
post #21 of 280
Thread Starter 
Quote:
Since 120V is the North American standard, the amp's internal voltages may be about 10% too high, possibly pushing the limits of the regulators in the power supply.
While this is technically true, this is highly doubtful. The voltage fluctuations here in China are rather great in some places, although things are getting much better each year - even at 10% higher voltage, the amp should be fine. But then, I will check with the seller anyway.


Quote:
So please check to see if the seller can convert it to 110V or if the wires are long enough to reach the other side of the transformer, or if the transformer has lugs on it (I suppose that means wires are not hot-wired into the transformer, but somehow connected to the transformer by screws or lugs.)
I will definately ask the seller about this issue.


Quote:
Just wondering how good would this thing be with low-impedance headphones, could this be useful with a pair of Grados? Eg., how would it compare to an RA-1?
Well, kelly in his review says:

To my surprise, all three of the headphones I had on hand--Grado HP-1, Sennheiser HD600/Cardas and Etymotic ER-4S/FixUp--performed equally well. Since all three are at very different impedances, I'm left to suspect the amp would pair easily with most headphones.

Although the SonicAdventure Reality is slightly different, it seems to pair well with low-impedance phones. I would suspect this is so for the HP-100A as well.


Regarding previous threads that mention the HP-100A being sold at cost and not being produced any more etc. etc... I called the company and the owner of 2000ok by cell phone and when I inquired about the HP-100A and its price etc. they did not give a hint that it was not available. I mean, the secretary gave me directions of ordering (how I have to first reserve, etc.) and the 2000ok guy said that I can come over to pick up the amps.

Well if it turns out that even after all the telephone conversations and my trip to Shenzhen that there is no amp, PayPal fortunately has a full refund function anyway (refunds all the paypal fees as well) so don't worry. There's nothing to lose.
post #22 of 280
Thread Starter 
Also, updated the payment schedule for international (non-US) buyers. PayPal seems to charge an extra bit for foreign transactions, I wasn't aware of this. Sorry about the confusion!
post #23 of 280
Doobooloo....


thanks
post #24 of 280
Thread Starter 
Good news!

I called up the 200ok guy today with my severely broken Chinese. But I got some positive information.

Regarding the voltage, it is possible to get them made @ 110V.
And, they will have enough by next week for around 10 units. He is going to give me a call sometime later to discuss the specifics (# of units, etc.) so I would like to get the final count soon.

Note that 5.5kg is 12.12lb, and I am only one man... This means that at least on the first trip to Shenzhen I will not be able to carry more than say, five or six of these units by myself. So currently I would like to limit the first round to FIVE UNITS. (So six including mine)

THE ONLY WAY TO RESERVE YOURS IS TO SEND ME A PAYPAL PAYMENT AS DESCRIBED ABOVE. ONE PAYMENT HAS ALREADY BEEN MADE. If more than five payments are made then I will promptly issue a complete refund (this includes all service fees so you get a 100% refund) to the later payers and make a note on this thread. If there's enough demand (say, another six people who really want this amp) then I may make another trip while I'm here until the second week of June if this first round group buy is successful... (No broken bones, ripped muscles, hurt feelings etc. )

So let me know (send me a payment) ASAP so that I can get the exact figure of which ones to order so that I can go pick them up next week. Also please specify if you want it converted to 110V or just leave them as 220V.

If you have any questions please feel free to post it on this thread or PM/email me. Thanks!
post #25 of 280
Ehh, Doobooloo. Why don't you just get them shipped from the manufacturer? They have an export license. So go over, check out the units, package it them up, slap mailing labels on 'em, call the EMS guys over and pay for everything.

Packaging is decent and the heavy chassis will survive rough shipping anyway. Heavy cardboard box with fitted foam pieces at the head and tail. (Total shipping weight should be 6.5 kg) You may want to check the power cable too. I got the funky 3 angled prong ones so popular in China. They have the standard grounded 2 straight blade cables too.

May I suggest that you have the manufacturer burn them in for at least 24 hours to check for problems. The local store here recieved 20 units last month, 1 unit kept switching itself off.

Thanks for organizing the group buy!
post #26 of 280
it might be cheaper to send them all to 1 US address and have them ship it out to others, i can volunteer =D sending payment for 1 AMP complete with russian tubes.
post #27 of 280

How about to SF instead?

Quote:
Originally Posted by ufokillerz
it might be cheaper to send them all to 1 US address and have them ship it out to others.
Hey, I was just thinking about the same idea! I live in San Francisco Bay Area, probably a better choice than shipping to New York first.
post #28 of 280
payment sent!!! please give me the US 110v version =D
doobooloo is from east coast also =P it would take just as long if he were to ship it when he gets home =P
i have a ppa to compare this to =D
i also have some chinese hydrid amp coming, well 10 of them modified for 110v run. will have to see if thats any good as well.
post #29 of 280
If you ship 5 or 10 amps in one shipment to one location, customs will most likely clamp down and ask for taxes. If you send 5 amps to 5 different addresses, you can label them gifts (although you're not really suppose to) and its more likely that taxes won't be assessed.
post #30 of 280
Thread Starter 
Quote:
Originally Posted by ufokillerz
it might be cheaper to send them all to 1 US address and have them ship it out to others, i can volunteer =D sending payment for 1 AMP complete with russian tubes.
Shipping it all together brings about quite a few complications. First, the shipping weight of the amp is 6.5, so with conventional methods that means only upto four amps can be shipped together. And that's at 26kg (57.32lb) which will require some extra packaging which will require a purchase of a strong enough large box which will further increase weight and... It's not that much cheaper either and shipping a 6.5kg box around the US isn't cheap either. And there's the customs issue mikeliao mentioned... IMO it's just not worth the trouble.

And yes when I send them I will label them as gifts. Even Audiocubes labels their shipments as gifts, I don't know if that's legal or not but...

What I will do when I get there is talk to 2000ok about somehow setting up an overseas distribution network for his product...

But anyway. It's going to be exciting to visit 2000ok...
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