Author Topic: Aion Blueshift opamps  (Read 608 times)

Invertiguy

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Aion Blueshift opamps
« on: July 29, 2023, 06:37:10 AM »
So I recently started on a second Aion Blueshift build and was in the process of drawing up a shopping list when I noticed that it calls for OPA2134s for the input buffer and pre and post filters, although the build docs do note that a TL072 will work fine (as will any other standard dual opamp most likely). Now the OPA2134 is certainly a fine opamp, but is it worth it here? The original Boss DC-2 definitely didn't use them and people seem to like them just fine, and I'd rather not spend $5-6 per chip when a sub-$1 part will work just as well. Is the lower noise floor and "clarity" that audiophiles rave about really worth an additional $8-10 in a guitar application? Interested in hearing everyone's thoughts.
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jwin615

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Re: Aion Blueshift opamps
« Reply #1 on: July 29, 2023, 09:49:46 AM »
In non drive pedal situations, I think it's beneficial in circuits running above 9v single rail.
I don't have any real scientific info to throw at you. Just my thoughts that if you are starting with a limited 9v headroom already, the noise of the rest of the circuit is already overpowering any benefit from "better" opamps.
But I also look at as one never gets into a hobby to save money. Yes, we can save money vs vintage unobtanium pedals, but you get but 100 different Chinese delays/choruses for under $50 as well.

In drive pedal situations, if there is an opamp stage acting as a clean boost/buffer at the front end, I'll happily throw a "better" opamp in there if it's suggested by the designer. Even minimal improvements in that situation are worth it, imo, as they become cumulative and magnified.
Now, I suppose you could flip that entire logic with, what if the delay comes before the drive in your chain? Well, the drive is going to boost the noise from the delay/chorus etc

In the end, it probably won't matter all that much though.
My .02

gordo

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Re: Aion Blueshift opamps
« Reply #2 on: July 29, 2023, 12:53:22 PM »
+1.  I've built one with 072's and one with Burr Brown's, and while I built them about a year apart so can't compare, I don't recall issues with either one.  It's a pretty pricey pedal to build anyway so saving a few bucks isn't likely to help and you can always play with different op amps once it's working and you like it.
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