2SA1302 and 2SC3281

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
I carried my stuff in in my personal luggage

Dear Ashok,

Sorry about the delay in replying.

You can order anything from abroad on int'l
ccard, provided you do not exceed the Basic
Travel Quote of forex (which the RBI gives each
citizen per head per year). This quota is, I
believe, USD 5000. Most of us never use any
of it for most of the years of our lives.

I asked Digikey US to ship the transistors to
my friend's place in Singapore. I was expected
to visit him (one of my very rare overseas trips)
and I picked up the packet and brought it in
with my personal luggage. The value of the
items was low enough to let me walk in through
the green channel, so no customs hassles.

On another occasion, I wanted to import a pair
of Jordan speaker drivers. I asked a friendly
neighbourhood hardware dealer to help; they
regularly import small quantities of specialised
hardware. He imported the items for me, got
them shipped in by DHL (the shipping costs
were 33% of the total bill), and then Customs
decided to charge no duty, saying the quantity
was too small; this must be a sample shipment.
Thus, I got them legally imported once again,
and delivered to my door, without any problems.

Hope this helps. I suggest that as a general
rule, pay by int'l ccard, and ask them to ship
to a friend's address who lives abroad, so that
someone coming into the country can carry
it with him. The second preference is to ask
for direct delivery to India. In that case, the
shipping costs will be heavy, and Customs
will definitely ask you to pay duty. Once they
realise this is for personal use and of low
value, they'll ask for some legal duty amt and
release the items without bothering to demand
bribes. On many occasions, if
the item comes in by DHL or some other
big int'l courier, Customs don't even charge
duty, I don't know why. If you ship directly
to India NEVER use any other shipping method
other than int'l couriers. Never use things like
air mail. Each time I've ordered books from
Amazon by air mail, they've got "lost" (Indian
euphemism for stolen by postal employees).

Tarun
 
Thanks Tarun.

Hi Tarun,
Thanks for the clarification.
Just before you replied I ordered some stuff , paid by credit card and shipped it to my pals place . This one was in the US but next time I am shipping to Singapore because it is easier to pick up. Note that if you can stay with friends it might be cheaper ( or almost ! ) to fly to Singapore yourself and pick up what you want. From Chennai it is about Rs 17K and from Cal it is even cheaper. Right now Chennai Delhi is more expensive than Chennai Singapore ! Actually it has been this way for several years.

How do the Jordans sound? Did you compare it with anythig else ?

Cheers.
Ashok.
 
The sound of the Jordans

Hi Ashok,

Built a small ported enclosure for each Jordan, based on one of the simple designs published on their Website. So, what with a 5.5" driver and a bookshelf enclosure, one does not expect to hear too much bass.

But after I built the boxes, stuck the speakers in (this was my very first DIY speaker building project with decent drivers) and went through the long break-in period, the sound was surprising.

The bass was weak. (I was comparing this with my Wharfedale Pacific PI-40 floorstanders, so it's no surprise.) But bass guitar in a lot of Western jazz music (including Diana Krall) sounded surprisingly deep; I had been expecting to almost not hear the bass guitars. However, there is an overall lightness in the sound because bass extension is poor. I can't expect anything else from a driver of this size, unless I try the floor-standing TL design on the Jordan Website.

The midrange is amazingly good. It's clearer than my Wharfedales, which are among the best Wharfedales built in recent times. I listen to a lot of Hindustani classical, and it's surprising how there's a discernible difference in clarity and detailing with just voices. It's like that cliche of a veil lifting.

The treble surprised me. There is little treble response. The response graphs of the drivers show the response stretching to 20K, even rising towards the very end. With my boxes, I find that even tape hiss is much less (yes, MUCH less) audible with the Jordans than my Wharfedales. As we know, tape hiss starts at something like 6KHz, so I was not mentally prepared to see a sharp audible difference at that low a frequency. I would think that one would need a tweeter, maybe cutting in at 8K and above, to fill in the upper registers.

Imaging is _lovely_ compared to my Wharfedales. (Reviewers of the Wharfedales have commented on them being a bit weak in the imaging department.) I don't know whether this big plus is due to the small enclosure or the Jordan or both.

Overall, the Jordans sound _lovely_. They give you about the lowest listening fatigue that I've ever heard, and they make you pay attention to the music; they're arresting (and not in a bad, overly detailed kind of way at all). Diana Krall sounds lovely. Sinatra sounds lacking in body. Hindustani classical vocal sounds lovely, both with male and female vocals; string instruments (e.g. Vilayat Khan's CDs) lose their leading edge a bit, but they remain hugely listenable, involving, and fun. Don't try rock; you'll need a 12" reinforcer for bass, I should think. I tried one of my favourites of good hard rock with super-clean recording: Dire Straits. Disappointing. Watching movies with 2-channel sound works beautifully with these speakers if the film does not have much pyrotechnics. If it's "Terminator 2", you need much deeper bass. I switch to the Wharfedales. :)

I feel my investment in the Jordans was a total success. I will discard the enclosure I built, and build a 3-way. I'll bring in a 12" driver for bass, below 200 Hz or so. I'll add a tweeter for the tape-hiss-and-above frequencies. I'll try open baffle, at least for the Jordan and the tweeter. And then we'll see how it goes. The midrange, the voices, from the Jordan, are absolutely first-rate. And a lot of people on the Speaker forum on this Website seem to have very similar ideas... use an FR driver as the centrepiece (in many ways) for a three ways with reinforcement at only the extremeties. And of course, I'll use active filters with amps from Randy Slone's designs. (That's how I got involved with these 2SA1302, etc. :) )

I'm also curious about the Tang Band drivers. If they can't handle high volumes, I guess it's possible to afford sets of four physical drivers... they are so inexpensive.

Tarun
 
Although I've been using 2SA1943/2SC5200 what I really like about someToshiba 2SA1302/2SC3281 pairs I also bought from digikey is that one on the right is green. (Or on the left it's going into a EF OPS). This may sound silly but as near vision gets a little manky with age it is embarasingly easy to get them wrong way around ojn the PCB!
 
MJL3281A & MJL1302A

PMA-

No, they are not the same chip. A little thing I learned a while ago in the electronics business: One manufacturer's 555 timer is not the same as another's 555 timer. They just subscribe to the same, very narrow set of criteria to be labelled a 555 timer. So while Motorola (excuse me, ON Semiconductor) calls theirs an MC1455, and National calls theirs an LM555, and SIgnetics calls theirs an NE555, they all have minor differeces, even though they all subscribe the "555" specification.

Same analogy holds for the Toshiba 2SC- and 2SA- transistors -v- the Motorola (there I go again! I mean ON Semiconductor) units. While the construction and semiconductor makeup may be different, both manufacturers' units conform to the same "1302" and "3281" criteria, respectively. Hence, the same base numbers of 1302 and 3281.

IMHO, the ON units are much better, as the formerly Motorola (There! I finally got it right!) company has unsurpassed quality control.

Beside, I doubt whether Toshiba will sample their units out. Believe me, try the sampling route- it's cheaper and it REALLY works!

Best of luck, and please let me know how you fare with acquiring these.
 
Toshiba -v- ON

Minor differences in how the silicon is grown, how the chip is assembled, the fact that the chips are assembled at different facilities using different construction materials and techniques, conforming to different quality-control standards.

I still think the ON units are slightly better.

Steve
 
Disabled Account
Joined 2003
Re: Toshiba -v- ON

N-Channel said:
Minor differences

Steve

those are pretty minor and in my view can be said about even the same chips made by the same company off the same waffer.

If that's all there is, I wouldn't call them different devices. electrically, they are pretty close.

I was hoping to hear that the teacher had some tricks up her sleeves. (Un?)fortunately in this case, the student (OnSemi) seem to have bested the teacher.
 
Teachers vs. Student after 17 years

Excuse me for reviving this antique conversation, but it is interesting to view the past from different point of view in time. What has changed meanwhile, over the past 17 years?

These days I somehow ended up with 8 pairs of ON Semi mjl and 8 pairs of UTC counterparts and two motherboards, each in need for 8 pairs. I was just curious to see how much ON is better than UTC before trashing the UTC devices and placing order for additional 8 pairs of the "originals".

After testing the both amplifiers for maximum power before onset of clipping and frequency response
I was astonished with results: they were indentical. Literally. Really, Chinese are good students and Motorola/Toshiba/Sanken were exceptional teachers.

The lesson learned: Chinese are too smart to risk and there is so much on stake to make bad copies. Just indentical are thes that count. From now on I will judge devices just based on reputation of supplier, not the producer.
 
Just to add that i see UTC regulators in never open not service,new Toshiba led t.v
Hello Thimios,
Obviously, you are much more experienced/informed. Could you tell us more about your view on the subject. Now I intend to place an order for more Chinese devices from different producers. My motive is not lower prices because transistors aren't the main cost at all, but I don't like to pay for extra snake oil. By the way, I prefer good Greek virgin olive oil. ;)
 
The lesson learned: Chinese are too smart to risk and there is so much on stake to make bad copies. Just indentical are thes that count. From now on I will judge devices just based on reputation of supplier, not the producer.

If you are careful this can be true. LCSC is a supplier I use, lots of far east manufacturers on their, but most of the stuff seems to be good.

A lot of it probably comes from the same factories the big names use. Remeber most of the stuff we use comes from the far east.

The difference between the good and bad stuff is quality control. The "bad copies" might be seconds/junk parts from a good run that should have been recycled/disposed of but magically ended up in the supply chain, on ebay or similar or occasionally from the good suppliers as I have found...
 
i am not sure that the Chinese have die foundries that can make the chips themselves, most likely they buy those dies/chips from ON semi and then do their own assemblies in house..

Sumitomo makes the lead frames and Dow Corning the plastic encapsulants...

Motorola, which later on became ON semis licensed these devices from Toshiba....
 
Member
Joined 2010
Paid Member
The problem for DIY folk, is knowing in advance whether the manufacturer and supplier are selling you a good/bad copy, an original part, a relabelled (as in sanded marking) one, a similar one with inferior performance in critical areas for your intended use, general purpose generic parts suited to low speed switching etc. When you buy from platform sellers, you may be buying good quality small components because these are very cheap to make but power transistors are typically poor copies or outright fakes in attempts to offer attractive deals.

On the other hand, Chinese manufacturers such as Inchange Semiconductor, are indeed large scale fabs that have been supplying OEM and replacement semis globally, for many years now. What's more, Inchange's logo isn't just printed on the package, it's moulded into larger size semis as "ISC", so they also take faking seriously and you can be more certain of getting what you paid for.

All the same, Inchange's and other Chinese products may well meet datasheet specifications but that doesn't mean that they use the same manufacturing process technology. I think we already know this is critical to audio quality in class AB amplifiers, where Toshiba and Onsemi's multi-emitter audio power transistors remain the preferred sources.

We'll see how long that tech supremacy lasts, as audio manufacturing continues to shift to class D as the new standard for domestic and commercial audio. Inevitably, the big players will move along to other products and process technologies to meet the demand.
 
Hello Thimios,
Obviously, you are much more experienced/informed. Could you tell us more about your view on the subject. Now I intend to place an order for more Chinese devices from different producers. My motive is not lower prices because transistors aren't the main cost at all, but I don't like to pay for extra snake oil. By the way, I prefer good Greek virgin olive oil. ;)

Never you must buy from China if you have the option to buy from an authorised supplier.
Even if the two parts is made in China. ;)
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.