"New Release Marantz & Sansui BA312 IC to Op-Amp Modification"

That looks like Hallo-Fi Electronics / BigVoyevoda.

Tony
If so, sketchy.
My question is WHY?
In all the years I've been doing this I haven't seen more than a few bad BA312 ICs.
To my knowledge, they are not an opamp, just a three transistor array.

Tom
 
There is a bit more in there than that if you look at the part data sheet. But I agree, I've only had one bad BA312 in over 130 rebuilds. But there are those always looking for a mod or improvement to turn their 2270 into an 2275. It's simpler to just buy a later model if you want more performance maybe? o_O
 
There is an old thread of a 9090db where Echowars replaced the BA312 for an OPA2604

Recapped with BlackGates in the signal path locations, replaced other bypass and filter caps (except the power supply caps) with Panasonic FC's, removed the BA312 opamps and replaced with one OPA2604, and built a +/- zener supply to feed the zeners (since the 9090db and many othet Sansui receivers have no low-voltage split supplies for a dual-supply opamp).
Worthwhile mods, but a lotta work...

Seems that Noah made an implementation in association with sparkos labs which allegedly is a nice upgrade to the units that use the BA312 on PE01 (2275 for example) leaving aside all the problems around hallo-fi etc etc...It seems that he will be the only guy doing it and he won't sell the module, so who knows how good will be the mod.:dunno:

Off course, there is no affiliation of my part.
 
Unfortunately given the fact that he has taken deposits and/or units from members here never to be heard from again(well documented) has me wondering about the credibility of this latest episode.
I actually felt sorry for him several years ago when he first ventured into wanting to do repairs and spent considerable time "mentoring" him.
He wanted a unit to work on but his starting funds were low.
I had a cosmetically nice 2230 that needed some tlc that he could have for $100 plus shipping.
He said he would send the funds in a few weeks.
I trusted him .
Sent the 2230.
Saw that it was delivered/signed for by him.
Texted/emailed and PM'd him.
Never heard from him again.

Saw that he sold it on eBay for $500 a few months later.

So you go ahead and ship your unit off to have this awe inspiring groundbreaking upgrade performed.
Let me know how it sounds.

Bob

ps-mention that he stills owes me $100
 
There is a bit more in there than that if you look at the part data sheet. But I agree, I've only had one bad BA312 in over 130 rebuilds. But there are those always looking for a mod or improvement to turn their 2270 into an 2275. It's simpler to just buy a later model if you want more performance maybe? o_O

The 2270 uses an all discrete tone amp, the 2275 uses the BA312. I find that the frequency response, distortion and noise performance are pretty much the same for both designs.
BA312 pinout.jpg


Tom
 
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So you go ahead and ship your unit off to have this awe inspiring groundbreaking upgrade performed.
Bob I'm sorry you had bad experiences with the guy.
That's why I said ''so who knows how good will be the mod'', after reading all the problems around him,I'm not THAT fool.
Maybe I should be more clear and say I that I'm not defending the guy or advertising his business.
@Jirachi , the guy making the mods have a bad reputation, he likes to charge in advance for the whole job, parts or units + job (not just deposits) and then don't answers calls or emails, that behaviour is unacceptable and take advantage of over enthusiast people who would love make an ''improvement'' on his gear, get it restored or buy a unit with such mods.

Than been said, I just find the 'upgrade' cool stuff to try (if he just sell the modules), but it won't be likely that anyone here give you an answer about how well it performs.
 
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Unfortunately given the fact that he has taken deposits and/or units from members here never to be heard from again(well documented) has me wondering about the credibility of this latest episode.
I actually felt sorry for him several years ago when he first ventured into wanting to do repairs and spent considerable time "mentoring" him.
He wanted a unit to work on but his starting funds were low.
I had a cosmetically nice 2230 that needed some tlc that he could have for $100 plus shipping.
He said he would send the funds in a few weeks.
I trusted him .
Sent the 2230.
Saw that it was delivered/signed for by him.
Texted/emailed and PM'd him.
Never heard from him again.

Saw that he sold it on eBay for $500 a few months later.

So you go ahead and ship your unit off to have this awe inspiring groundbreaking upgrade performed.
Let me know how it sounds.

Bob

ps-mention that he stills owes me $100



That is a sad story.

Tony
 
^^^ Tom and I also invested time in mentoring him too and I bet more AKers. Truly, it was sad but I'm over it. I'm not $100 in arrears though! That WOULD piss me off and it does as I consider Bob a friend.
 
It's more about the betrayal of trust than anything else.
This hobby can really use some up and coming younger techs to fill the shoes of the older guys who won't be around forever.
It's takes awhile to gain that knowledge and experience and level of trust to be able to take on repair/restoration work from others who send you their units to come back to them better than ever without having to wonder if they'll ever see them again.


Bob
 
An interesting idea I suppose, and if it weren't for the individual behind it, I'd probably be curious enough to buy a kit.
 
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^^^ Tom and I also invested time in mentoring him too and I bet more AKers. Truly, it was sad but I'm over it. I'm not $100 in arrears though! That WOULD piss me off and it does as I consider Bob a friend.

Add me to the mentoring club too.
 
1) Unnecessary physical size
2) Astronomical price as one apply them in pairs or more
3) Must ship unit in for installation which denotes additional labor charges beyond shipping
4) etc.
 
Wow! I had no idea about this guy. He does sell the BA312 upgrade modules under the name AnalogEsoteric. I purchased a pair on the bay and just installed them yesterday. They are definitely an improvement and after reading this thread I will be buying another pair before he goes out of business or to jail. That said, I can't believe anyone would send off their vintage equipment AND pay in advance to get it restored. That's just asking for trouble.
 
Hi guys. I have good news on this. Sparkos Labs (me) has taken over the production and sales of the BA312 upgrade kits from Analog Esoteric. Noah approached me to develop this upgrade that he originally wanted to use in his restorations. We developed it, and I then convinced him to sell the kits which he was doing up until this weekend. He doesnt want to continue to sell the kits as that is not part of his core business, so we have taken over the manufacture and sale of these modules. We have reduced the price and are also offering whole sale pricing to other vintage restoration shops who are interested in doing this upgrade for their customers.

I havent quite got all of the info up on my website (SparkosLabs.com) but am working on that now. Hopefully by the end of this weekend we will have something up.

This mod is great and offers a flatter frequency response, lower distortion, and lower noise floor over the original BA312, which was little more than a two transistor gain stage.

Get ahold of me either here or (preferably) on my website if anyone is interested or wants to know more.
 
The management here tend to frown upon vendors soliciting business on this site without paying for the advertising. Just a heads up.
 
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