Aion Prism (Boss FA-1 clone) build issue

[Elvis Cocho]

Hello. Any help would be appreciated.

I built an Aion prism with intent on using the HA1457W op amp. I got a batch of 10 from eBay and I noticed when I finished the build, the circuit was weird. I got barely unity with the volume at 0% and I got zero volume at 100% on the volume knob. Bass, treble and the low cut switch did nothing.

I checked all resistor and pot values; everything is where it should be. I ended up socketing in an RC4558 and the pedal works as it should.  But why not with the HA1457W? Did I really get all 10 op amps to be bad? That's just too weird. By the way, I've built around 10 or so pedals from the Aion pcb's including two Blueshifts, so this is not my first rodeo.

A word about the HA1457W: it's different from other op amps I'm used to working with. It's an 8-pin Single In-line package and there's a gap where a pin would be between the far left pin and the next pin to its right.

If there's any low-hanging fruit I can check, DC voltages in places, waveforms i should see at op amp pins, any advice anyone can give would be super helpful. I can post pics if need be as well. Thank you in advance.

[aion]

I can at least confirm the HA1457W does have a gap in it (the pad on the PCB is unconnected) but beyond that I don't have one put together at the moment so I can't give you any voltages unfortunately.

I would just use a MC1458 (LM1458) and be done with it. It's identical to two 1457's in a single package, I've done lots of listening tests (as have others) and it's indistinguishable!

[PRR]

DIYstompboxes.com - Oct 9, 2005 - HA1457W opamps in there, and these are more rare than natural boobs in Hollywood.

If they were rare in 2005, maybe rarer now

> just use a MC1458 (LM1458)

This. The 1457 is a high-spec '741/'1458-family opamp.
http://nice.kaze.com/av/HA1457.pdf
It was promoted as a RIAA phono preamp. Maybe they made too many for the declining phono market and BOSS bought the surplus. BOSS doesn't use the opamps for "flavor", just gain and bass/treb knobs. I see no audio reason the two '1457 can't be replaced with a 1458, 1558, or even the new-kid TL07x. (Ah- just as shown on Aion's PDF.) Ignore the 100pFd caps the '1457 needs.

[Elvis Cocho]

It kind of feels womp womp to build a circuit and have to use a modern off-the-shelf op amp instead of the old obscure vintage ones just to get it to work. But I can say that on its own merits the circuit is really cool and unique.

I think it's really great that the aion pcb's have the flexibility to allow for a dual chip to be used instead of only the two single op-amps. It has literally made all the difference for me in building a working pedal as opposed to building a brick.

Im still going to put it on faith that I just have a bad batch of op amps. I ordered some new ones hoping that I can pop and swap when I get them. If that doesn't work, I'm okay with a dual chip.

[PRR]

> have to use a modern off-the-shelf op amp

The '1458 is very old, older than '1457.

The vast majority of pedal opamps are minor variations on the '101/'301. The '741 put the compensation cap inside. The '1458 is two slightly improved '741. New Japan Radio has made a business of grooming "741 types" with different device proportions for less hiss, more output current, higher speed.

There's no reason BOSS used the '1457. Speculation: it does not matter, and a truckload of '1457 was available cheap enough to justify a PCB layout.

[aion]

Small Bear's 1457 chips are legitimate, but you're rolling dice buying NOS chips from eBay. The 1457 is unlikely to be straight-up faked since it's so obscure, but they're most likely pulls from discarded electronics and so there's very little chance they have been tested. In some cases they're even factory rejects - maybe someone finds a bin of them that had been set aside several years ago, and starts selling them without knowing that they were set aside in the first place for a good reason.

I was involved in the development of a commercial clone of the FA-1 a few years ago and we did extensive listening tests against a real FA-1. I built up one Prism with a 1458 and one with the HA1457. They was passed around some studios in LA along with the original FA-1 to well-known session musicians who have been using FA-1's for years, and no one was able to distinguish any of the three from each other.

I am very much averse to "close enough" approximations of vintage circuits - so when I say the 1458 is the same, I mean the same! Like using a TL072 instead of two TL071s.

A new version of the Prism will coming out in the next few weeks and it will drop support for the 1457 entirely, with just the dual op-amp.

[Elvis Cocho]

Hi everyone,

Ok. Update on my build. I suspected that I got dittled and was sent either bad chips or the wrong ones altogether. I ordered a set of 5 from a US dealer and paid a little more than I would have for a set from a China seller.

I got them today. I popped out the rc4558 and popped in the new HA1457W's I got. The first two worked perfectly. No issues whatsoever. My pedal works as expected and with the vintage set of chips.

I honestly find it jaw dropping that all of the ones I received from China didn't work. It was like 10 of them. I was expecting maybe for a couple to be bad, but surely I could find a good pair in there. Nope, not a single one. Man, I wish they just had better quality control over there with what they send. Especially because it takes six weeks or so to get anything from China.

Happy ending. My pedal works and it has the vintage chips. Of course, I wasn't expecting a night-and-day sonic difference between the vintage chips and the modern ones because i know that the sound of a pedal and it's frequency response comes from the sum of its parts rather than one or two components alone. Still, I happen to find added value in building replicas of effects using the same old components. It's like building a piece of history 

[PRR]

> jaw dropping that all of the ones I received from China didn't work. It was like 10 of them. I was expecting maybe for a couple to be bad, but surely I could find a good pair in there.

Ten from the same vendor, the same batch??

[Elvis Cocho]

Yeah. Every single one in the batch from the same vendor was bunk. Pretty disappointed at that.

[PRR]

I figure: if a vendor is selling outright FAKES, why the heck would he have ANY genuines in the house?

There is a pathological market here. Over 90% of e-parts bought at low price on e-Bay will NEVER be used. They get bought for "future projects". Which do not happen for years if ever. And of the few that get used "soon", the builder may be unable to tell WHICH of the low-price parts (or his own work!) is the reason for failure. So maybe 2% of sales lead to a complaint and refund.

dummy part: $0.01
re-marking: $0.01
sales price: $0.20
gross profit: $0.18
2% refunds: $0.004
nett profit: $0.176

Please do not buy "cheep" parts on eBay. Fakes are much too easy. Dead parts of any shape or pin-count are a glut in Asian alleys, and part-markers are readily available in those same alleys.

[Elvis Cocho]

If you happen to know of a reliable seller that can provide chips such as:

MN3005, MN3007, MN3101, MN3102, MN3205, MN3207, NE570, HA1457W... basically any chip for DIY guitar projects, I would really like to know. This also applies to older JFETs, MOSFETs and BJT's. Often times, I can't really just find them online in places other than eBay. Mouser and DigiKey are way too contempo and don't carry them. I'm actually trying like heck to get some MN3102, MN3207 pairs for a different project right now and I can't find them other than from eBay sellers.

If you have a viable solution to this problem, please share it. I'd be ever grateful. By the way, the chips I got that solved my problem with this build were from an eBay seller. I went out of my way to find a US seller this time though.

[PRR]

Small Bear Electronics is known for supporting small commercial pedal builders, who can't be fooling with fakes, and are happy to pay a fair price instead of an auction price. Sadly he works in a dense part of NYC with many dear friends so he is mostly shut-down until the virus burns-out.

Mouser and DigiKey are as honest and diligent as any company can be with >1 million parts in catalogs. As you say, 999,000 of those parts don't make sense in pedals which clouds any search, and they do not bother with the really odd old parts pedals still use.

Electronic Goldmine https://www.goldmine-elec-products.com/ is an odd-lot surplus house with a lot of amazing deals you mostly do not want. (Today a lot of Geiger counter bits.)

[bluelagoon]

Hey Elvis, Glad that you got your legitimate HA1457W chips and your FA-1 working and sounding as it should.
The problem with purchasing these Ha1457W IC chips these days, whether from ebay or Aliexpress is that they are mostly being sold out of China, whereby the sellers represent them with picture images of the original legitimate Hitachi IC's, but when receiving them, upon delivery, sadly they are not the same chips as represented in the advertised item images. They look similar as SIP inline 8 pin IC's with the second pin missing, they even have the same HA1457W written on them and some similar Hitachi trademark symbol, but they do not have the same stripe to the left nor is any of the printing done in the familiar silver type print.
Sadly I have been duped on many occasions purchasing these chips believing them to be as advertised, and then being on the receipt of yet again another lot of Fakes, and for me I didn't get the chance to test any of them till a year or so after purchase since were still using original Hitachi chips for the effects I were making.
Once started testing them in the FA-1 circuit, I quickly found same as you did, that none of them work in the FA-1 circuit and do characteristically exactly as you stated in your opening post.
I have yet to test these chips independently in any other circuits so cannot say their viability for any other uses, but they definitely are not HA1457W Hitachi chips.
Since I were so slow to test these, I could not recall which sellers I had purchased from in amongst the ones received, where some lots were originals and some fakes, so sadly I had no recourse to get back to the sellers with a complaint.
  I am now stuck with about 40 to 50 of these fake HA1457W chips at great expense and an ultimate loss.
I wouldn't feel good to be on selling them, knowing they are duds, so sadly are stuck with the loss.
Now days if a seller cannot or will not send any up to date images of actual item being sold I do not purchase them.
Just recently I petitioned a major online seller out of Europe, "Banzai Music GmbH" for an updated pic of their HA1457W chips, they sent an image of the exact same ones I have that I know to be fakes. I advised them on the fact they are fakes and do not work as they should. They said they will look into it. 6 weeks later their add for the same still stands. Some sellers are just unscrupulous and don't care nothing but your money in their hands.
Check the image attached here it shows the actual chips that are the fake chips they are all marked as 8M4 HA1457W
I suspect these would be same as what Elvis also had the misfortune to receive.

Cheers

[bluelagoon]

Happy ending. My pedal works and it has the vintage chips. Of course, I wasn't expecting a night-and-day sonic difference between the vintage chips and the modern ones because i know that the sound of a pedal and it's frequency response comes from the sum of its parts rather than one or two components alone. Still, I happen to find added value in building replicas of effects using the same old components. It's like building a piece of history

As for your remark on the Ha 1457 not sounding distinctly any different than modern updated op amps. Well you couldn't be any more wrong. The HA1457W is the heart and soul of the FA-1 effect sound. the sound of the FA-1 isn't made up of the sum of all components so much that there is no noticeable difference between installed op amp chips. What I have found after making close to 50 or more these FA-1 boxes is that you can interchange any of the other components, the Capacitors the Resistors and even to some extent the Fet transistor, not the actual values but to different type components and nothing affects the output of the FA-1 any differently other than when you substitute in alternative op amp chips. I have tried many different op amp substitute chips, some high end and none truly represent the original FA-1 sound with its unique nuances of tone, attack, decay, compression etc. as distinctly the Boss FA-1 original is renown for. Sure they are still musically well enough tasteful, but to a different
type feel and sound, which cant be replicated without the Hitachi original HA1457W.

Which gets me quite miffed when I see some selling repro's on the original, the likes of the Clover, which from all accounts is likely a very fine effect with the extra addition of a switchable midrange facility, and yet it doesn't have original FA-1 type op amps installed, to me that just detracts from its
ability to truly represent the original Boss Fa-1 in its true sense.

And now that the original Chips are like hens teeth, the ability to reproduce the original FA-1 sound is now so much more unreachable.

Cheers