The Opamp thread

[HeyManslowdown97]

There's a thread on DIYaudio about the OPA1656, with a guy from TI telling very useful things.

One thing is that TI is not sending samples when request comes from private mail services like gmail and similar. Only companies.

He suggested to buy the parts direct from TI.

Marketing 101 by having one of the engineers on the diy threads because it creates interest (especially from spec crazy diy-ers who “need” the lastest and best specs and use “word of mouth” via the audiophile threads to push cost up by popular demand) They do outsource them to official distributors ie Mouser, Digi-Key but you have to buy them in bulk (we’re talking 100s to 1000s) and you have to ”quote” this usually is dealt with by material managers.

Like I said previously the little guy isn't who they want unless he/she buys in bulk!

The shipping alone cost more than the opa amp!

You'll have to wait when its readily available or pay the shipping cost from TI which is double what the op amp cost is.This why they are profitable and stay in business

However, Trump tariffs from China cost companies million for cents on the dollar extra is past along the customer likely these chips will NEVER be made there because the Chinese steal the IP already unless its from Foxconn which is a Taiwanese company not Chinese.

Hong Kong is strategic in the region and despite pressure from BEIJING remains independent (somewhat). It’s trying to maintain its British rule but it’s getting harder and harder for them since it was given back to China back in 1999.

The big tech companies want it both ways. Google has its servers located in Hong Kong and claim they do serve mainland China that isn’t censored by the Chinese government (which is true) but they also have commercial interest in data mining as well.

Lots of people don’t see the forest from the trees. There lots of gray areas my friend.

 

[carlmart]

Some info you said seems to be wrong. The price is $2.56 and you have to buy a minimum of 5.

I doubt they will charge an expensive shipping, or even if they will charge one within the USA. They are interested that companies try their product, only they want to be sure who does.

I can simulate ordering through my cousin's small company in California and see what happens. It's a small company that fulfills TI requirements, as it deals with electronics prototypes.

As I we were thinking of prototyping a RIAA preamp, I'm interested.

The only thing I learned yesterday is that the OPA1656 has a CMOS input, not JFET, as I would prefer it to have. It's fine for a headphone amp. but I'm not sure for a RIAA

 

[HeyManslowdown97]

Some info you said seems to be wrong. The price is $2.56 and you have to buy a minimum of 5.

I doubt they will charge an expensive shipping, or even if they will charge one within the USA. They are interested that companies try their product, only they want to be sure who does.

I can simulate ordering through my cousin's small company in California and see what happens. It's a small company that fulfills TI requirements, as it deals with electronics prototypes.

As I we were thinking of prototyping a RIAA preamp, I'm interested.

The only thing I learned yesterday is that the OPA1656 has a CMOS input, not JFET, as I would prefer it to have. It's fine for a headphone amp. but I'm not sure for a RIAA

I have ordered from them before. You don’t have to buy 5 of them nor be a company (although they ask for what purposes you using their products; it’s just a default setting. You can adjust the quantity (it’s just a bit tricky).

They may give you a discount since your cousin is a company NOT an individual (like aforementioned). Although, they wouldn’t ship something that’s national defense sensitive so in this case yes they want to know what you are using it for and registering it but for an op amp it’s not that sensitive. They do however have it to comply with federal and state laws. Sadly though there are loopholes like establishing shell companies but the feds are cracking down on that especially after recent events in the states with foreign adversaries (and rightfully so).

They charge nearly 3 dollars per package because it’s package well. (Which is most likely well below what they ship for and what the shipping materials cost).

So when you do the math it cost them say 60 cents to produce one chip (that’s a modest figure) and you pay $2.56 that’s nearly 300% of what profit and is resulting in fixed price set by the board and if profits and units goes up as well as sales that is reflected in the stock prices but of course other factors go into stock price like product launches and supply chain issues, etc.

I’m ok with it. I’m just telling how to do the evaluation in terms of what the company is worth and how makes money. The choices is of course up to demand as it determines the supply.

For instance, Rio is the murder capital of the world someone is making money on the infiltrating guns into the black money because of demand. That’s why your president thinks its smart to give citizens the right to bear arms which is also a profitable market black or otherwise. (Take it from an American who deals with Mass Shooting every 6 months or so and Gun violence is one among the highest in the industrialize nations: mo’ gun, mo’ problems and less safe because you are dealing with availability)

I prefer JFETs myself but the markets seems to pander to the portable market which is headphones and like I said I don’t like CMOS because of high gain and regardless how low the noise is you can still sense it in the frequencies but many headphone enthusiasts love that kind of power, volume and to power their low impedience headphones. The demand dictates the market not the other way around. Unless it’s a company like Apple which can be didactical since isheep will buy their products regardless...

 

[carlmart]

According to the TI person collaborating in DIYAudio, not matter what it may bave been in the past, now TI ONLY sell to companies, quite likely based in the US. No exceptions for individuals.

I remember, from the time manufacturers did send samples, that you had to declare several things. Then they stopped sending samples.

In the case of Brazil it was because they sent it through couriers. Samples were then required to pay import taxes, but if they went through customs only. With courier companies they always take things through customs, so you are always required to pay taxes,

For a short time the manufacturers paid for the import taxes, and then they stopped. So no samples anymore.

I'm not sure which is the sample policy within the USA with TI. Other companies, like THAT, do send free samples through their customer engineers. I don't imagine TI having that. They did in the past, but not now.

The product price is what it is. You pay it or not. I think the AD745, recommended for RIAA preamps, is too expensive ($15) and I will not buy it.

Our present president is a mad man. The guns laws he intents to pass will not get through, and he has already backed up about down.

He doesn't know how to deal with Congress, and wishes the military dictatorship (which he claims it didn't exist) was still going and he was president, with no Congress. He forgets that being a captain, as he was before he was expelled, it would be likely to be elected president.

Well, this is no place to speaks politics and we might get a warning. Let's stick to electronics.

 

[HeyManslowdown97]

According to the TI person collaborating in DIYAudio, not matter what it may bave been in the past, now TI ONLY sell to companies, quite likely based in the US. No exceptions for individuals.

I remember, from the time manufacturers did send samples, that you had to declare several things. Then they stopped sending samples.

In the case of Brazil it was because they sent it through couriers. Samples were then required to pay import taxes, but if they went through customs only. With courier companies they always take things through customs, so you are always required to pay taxes,

For a short time the manufacturers paid for the import taxes, and then they stopped. So no samples anymore.

I'm not sure which is the sample policy within the USA with TI. Other companies, like THAT, do send free samples through their customer engineers. I don't imagine TI having that. They did in the past, but not now.

The product price is what it is. You pay it or not. I think the AD745, recommended for RIAA preamps, is too expensive ($15) and I will not buy it.

Our present president is a mad man. The guns laws he intents to pass will not get through, and he has already backed up about down.

He doesn't know how to deal with Congress, and wishes the military dictatorship (which he claims it didn't exist) was still going and he was president, with no Congress. He forgets that being a captain, as he was before he was expelled, it would be likely to be elected president.

Well, this is no place to speaks politics and we might get a warning. Let's stick to electronics.

I feel you because I am cheap (haha) but out of Principles most times. Yea I always wonder why some amps cost so much and some not much.

15 is not bad if you only need say one but it can get pretty cost (especially if you don’t know if you’ll like it or a building on a budget).

(I just invested in a ultra low phase oscillator because it will clock better and sound better (which maybe wishful thinking on my part) they can be equally expensive as op amps)

They will sell it to individuals but you have to register. Just no more samples since it didn’t garner more business for TI (which is fair). They’d rather sell to companies since if it’s “hit” in a commercial device it’s the first thing they will advertise as a “feature.”

I believe the Opa1656 are great and it’s not the much at 2.56 + shipping is STILL not a bad deal but I know it’s hard outside the US other than Europe, Australia and New Zealand

CMOS are innovative and as there is more detail with hardly any distortion but you have to Listen to them at a reasonable level because they are Extemely strong with powerful headphones and should have disclaimer but that’s not a problem you.

I don’t thinking using it in a RIAA will be bad it’s just that may not get the nuances it was designed for as a headphone amp.

The Opa1652 is pretty nice I’ve been listening to it for a day and half so I believe the Opa1656 may be worth it with minimal economic risk! With Powerful CMOS headphone op amps they are great, you just have to be careful not to crank it up for health reason and fatigue.

Dude, it’s crazy town here (I’ll just leave it at that) Haha

 

[raoultrifan]

[...]
@raoultrifan Dude I gonna pick up the Opa1612 next purchase but the OPA1652AIDR was 2 bucks cheaper and well let’s not be pc...I’m cheap haha

I'm using OPA1652 in Matrix HPA-3B with great success, it's in Voltage-Amplification-Stage. The background noise is lower than MUSES01/02/8820/8920, LME49860 a.s.o. No overheating, no oscillations, voltage rails are +/-15V.

Sometimes I'm switching them both with BURSON SS V6 Classic duals, depending on my mood, although....without proper A/B testing I can't actually tell about the differences.

I do recommend OPA1652 in voltage gain stages!

 

[HeyManslowdown97]

I'm using OPA1652 in Matrix HPA-3B with great success, it's in Voltage-Amplification-Stage. The background noise is lower than MUSES01/02/8820/8920, LME49860 a.s.o. No overheating, no oscillations, voltage rails are +/-15V.

Sometimes I'm switching them both with BURSON SS V6 Classic duals, depending on my mood, although....without proper A/B testing I can't actually tell about the differences.

I do recommend OPA1652 in voltage gain stages!

I like it too! The funny thing about the Opa1652 is that it took a half day to really sound good, I'm not that much of a believer in the ”burn in” sounding better but I have found it takes time for newer components to be ”accepted” by a DAC to become an IC. (pun intended) IMO anyway.

I've been told that switches aren't good for audio so the Opa1652 really makes up with voltage gain if there are flaws in the DAC. It's pretty impressive how some opa amps and other chips are made to ”make up” for poorly designed or ”shortcuts” by engineer to save space.

Ordered the opa1656 and the new BUF634A. They are both in ”Protocol” stage so I don't know how much along they are in final stage of release they will be when I get them but I'm fairy confident they are pretty close.

Updated: Just looked up the Matrix HPA-3B and it looks pretty rad. It's something I'd entertain getting in the future. Really love XLR balanced but never used them in headphones! Didn't even know they had a cable for them. Lol.

Updated Friday April 26, 2019:

Received both BUF634A & Opa1656 respectably Thurs and Fri. (Today) afternoon.

Both are great and aren’t the most aesthetically appealing for sound (which isn’t their main objectives and what makes them exceptional).

The BUF634 is EXTREMELY Powerful and should only be used in buffering situations for headphone drivers or boosting current I would say in my opinions. It’s gotta be great in the right situation, for me, just haven’t found it yet!

The Opa1656 I received today is exceptional not something you wanna use as a “solo” act op amp but differently a must (imo) in a lpf or to drive headphones or even speakers (haven’t tried speakers yet to confirm though). Not the most characteristic op amp with “great” sound but it’s soundstage is dynamic and far reaching that WILL drive a more pleasant sounding “diva” star op amp like the usual suspects AD797 or the Opa627 or your favorite op amp to ecstasy in your ears reaching pure nirvana!

It just brings out THE best in all your favorite sound op amps that you love while give them something extra while making up for their shortcomings.

It’s still early but I can safely say the opa1656 is a special one as far as THE ultimate utility “operational” amp that makes ANY great sounding op amp sound nearly blissfully perfect!

It’s a bit trembly but not annoying just not as bassy sounding (which most of my music pallet favors). I find most of TIs op amp especially Burr-Browns (which this is) are sound wise are balanced and neutral but great in my opinion.

Again not the “star” op amp that everyone goes crazy for but what makes the star op amp shine!

 

[LaughMoreDaily]

My current favorite opamp: OPA1642. I took out the Audio Jade AD797BR from my Zishan Z1 because it's too dark. Would the AR sound brighter?

I thought I would love it... but nope. $30 gone.

 

[HeyManslowdown97]

My current favorite opamp: OPA1642. I took out the Audio Jade AD797BR from my Zishan Z1 because it's too dark. Would the AR sound brighter?

I thought I would love it... but nope. $30 gone.

Yea- the Zishans Z1 & Z3 run a bit “dark” and bassy to begin with in my opinion.

The problem I believe is the clock frequency is set too low. 11.052 (always forget the exact number). You can toy with the resistors values to open up the sound but it may cause it to instability.

(I read that you can get the correct resistance value by dividing the current and the voltage but you'll first need to measure it with an accurate multimeter to get the variables)

I haven't really played with the firmware but if it's not encrypted and with little bit of research you can recode the frequency to a higher frequency (its actually something ill experiment with at some point). It's gonna be a challenge but if you take calculated risk you'll no doubt learn valuable knowledge going through process (this is how I've learned the most hardened and rewarding lessons)

Keep in mind your ”success rate” is not in your favor as a beginner but worth the journey!

The Opa1652 and Opa1656 sound fantastic in those zishans I had both as buffers and they really brought out the best in driving my favorite op amps. Currently rocking the BUF634AU in it.

I’d rec them to anyone rocking the z1!

Just got the Zishan ak4495 today and just in stock its THE best sound one, I’ve tried in the series!

I cant wait to get my hands in and mod!

The AD797BR by Analog Device is awesome it may have been wiser to have gone with the original not the Audio Jack??. you just have to find a killer DAC for it especially if you need more darkness (or cowbell).

 

[LaughMoreDaily]

The Opa1652 and Opa1656 sound fantastic in those zishans I had both as buffers and they really brought out the best in driving my favorite op amps. Currently rocking the BUF634AU in it. I’d rec them to anyone rocking the z1!

What do you mean by, used them as buffers? Is that the technical term for using them as sound chips in the device?

 

[LaughMoreDaily]

Just got the Zishan ak4495 today and just in stock its THE best sound one, I’ve tried in the series!

Youve heard every version of the Zishan DSD?

 

[HeyManslowdown97]

Youve heard every version of the Zishan DSD?

Yes I now have both versions of Zishan “DSD” the Ak4497 and the ak4495. The latter is the older version of the two. Price wise they are relatively priced evenly the ak4495 is slightly more and in my opinion has a better circuit layout despite having the “inferior” chip.

The Ak4497 was the most up-to-date chip until this month when the Ak4499 dropped. (I’ll wait until they come out with a Zishan one).

The YUGE advantage of the Ak4499 vs the others’ is a. It’s runs on current not voltage which is interesting and not traditional b. It’s 4 channels not 2 channels which is pretty cool!

I’ll wait until more advanced modders sort out it’s kinks and it’s been on the market for awhile!

These chi-dacs have major electrical problems mainly because they have inferior counterfeit components relative to the Western genuine parts and markets but cost way less and aren’t “copyrighted”.

Really fun to learn on circuitry wise as an Intro to Basic dac making.

*To be honest I don’t know what it’s called I only referred to it as the “buffer” since the stock Z3 comes with a fake “Buf634”.

Essentially the Z1, Z3 are both Dacs and headphone amps all-in-one.

The buffer dual amps powers your opa1642 in the final stage.

(*Honestly I’m not the most über knowledgeable about the terminology (although it does help to use correct terms on threads so people know what you are talking about) but Ima relative beginner so I just give myself a lot of leeway (even when some snooty “expert” with more “experience” tries to give me crap about not knowing anything.)

The dual amp that drives your headphones is what you want to pair your opa1642 with the two op amps I aforementioned. However it’s gonna require soldering if you are comfortable with that there are other mods that can greatly improve your Zishan sound but require some experience with a hot air soldering rework station.

I just ordered the opa1612 to put in the lpf of my Zishan ak4497eq. Super stoked to put those bad boys in as I’ve heard nothing but great things about those op amps.

I’ll also add that all the op amps that I mentioned are wayyyy cheaper than the AD797 30 bucks so you can op amp roll and experiment with more variety to see if one fits your sound.

Most can be sourced at Arrow.com that’s located in the states so if you order before 5 PC coast time you’ll get it at your doorstep the very next morning in Canada fed ex ed. Not sure if that’s true for exports to Canada these days sadly with this useful idiot running the his show!

 

[Spektykles]

Just finished some basic portable stuff with 3x P(rototype)-OPA1656 and 2x OPA1688 in parallel, wow 1656 heat up like hell compare to 1652 in this same system. still in burn in phase (yes a believer here )

 

[LaughMoreDaily]

I’ll also add that all the op amps that I mentioned are wayyyy cheaper than the AD797 30 bucks so you can op amp roll and experiment with more variety to see if one fits your sound.

I'm not a fan of the Audio Jade AD797BR it's not as clear as my 1622 but the mids are more forward and it's more musical than the 1622 but the blurry music is a downer.

 

[HeyManslowdown97]

I'm not a fan of the Audio Jade AD797BR it's not as clear as my 1622 but the middle are more forward and it's more musical than the 1622 but the blurry music is a downer.

I hear you. Follow your sound and trust your ears there's no ”perfect” op amp just the perfect one(s) for you!

The 1622 is a nice all encompassing op amp. It gets a lot of nuance in your music. I like it as a headphone amp (as it was intended to be used). I have to be in the mood to crank it up but it gets distorted! For me, it’s not “distortion” like it sounds “bad” it’s just hits certain frequencies that makes my ears hurt from the sound pressure with fatigue that turns into “white noise” for me. (My ears are very sensitive to pressure and “blow” similar to crappy speakers, lol). The opa1622 is very powerful and some are generally attracted to it because of its outstanding benchmark spec sheet scores. The 1688 is very similar sounding I've heard but it's got the added advantage of being in soic package!

The opa1656 has what the 1622 has and then some (it’s VERY clear)! In my experience It's a little unstable because it’s still in protocol and I doubt nobody knows yet how to harness it proper yet but when it’s on, it’s amazing!

These days we are spoiled with so many choices and your sound should be personal so there’s no right answer.

You would love the Opa828 or the Opa827.

Both are really nice and exactly what you describe you’d like. You'll need two of them along with a adapter but they are pretty rad!