[sdiy] The TL074 has changed!

[mark verbos]

You aren’t using tube gain stages? Are yours even analog?




> On Aug 2, 2025, at 13:36, Vladimir Pantelic via Synth-diy <synth-diy at synth-diy.org> wrote:
> 
> don't you all build your own discrete opamps???
> 
> On Sat, Aug 2, 2025, 13:20 Doug Jackson via Synth-diy <synth-diy at synth-diy.org <mailto:synth-diy at synth-diy.org>> wrote:
>> TL074....  TL074...   
>> 
>> We all know that Gods own opamp is the 741...
>> 
>> Get off my lawn :-)
>> 
>> On Sat, 2 Aug 2025, 7:04 pm Mike Bryant, <mbryant at futurehorizons.com <mailto:mbryant at futurehorizons.com>> wrote:
>>> I'll add to this - the new one is crap !!   I used to use the TL07x series in low cost mic-amps and other mixer circuits but the H series are noisy as hell.   I just specify other manufacturers now.  
>>> 
>>> They really should have given this opamp a different part number - it's simply not a compatible device, even if it fixes known issues.
>>> From: Synth-diy <synth-diy-bounces at synth-diy.org <mailto:synth-diy-bounces at synth-diy.org>> on behalf of Jay Schwichtenberg via Synth-diy <synth-diy at synth-diy.org <mailto:synth-diy at synth-diy.org>>
>>> Sent: 02 August 2025 06:30
>>> To: synth-diy at synth-diy.org <mailto:synth-diy at synth-diy.org> <synth-diy at synth-diy.org <mailto:synth-diy at synth-diy.org>>
>>> Subject: Re: [sdiy] The TL074 has changed!
>>>  
>>> Mike,
>>> 
>>> Would you please share your experiences about the new chip not working 
>>> for you?
>>> 
>>> Thank you.
>>> Jay S.
>>> 
>>> On 8/1/2025 5:23 PM, Mike Beauchamp wrote:
>>> > Last week I received an order of partially assembled prototype PCBs. 
>>> > It's a rather large circuit, with the bulk of the IC's being the 
>>> > venerable Texas Instruments TL074C that I've been using for 15 years.
>>> >
>>> > Compared to the previous boards, I immediately noticed that the power 
>>> > consumption was way lower on this batch - from ~16W down to 11.8W, 
>>> > definitely significant. That is about 1/4W less power per TL074.
>>> >
>>> > After some snooping with the help of people on forums, it seems as 
>>> > though Texas Instruments changed fab processes ( 
>>> > https://media.digikey.com/pdf/PCNs/Texas%20Instruments/PCN20221219006.1.pdf 
>>> > ). The new version has been around for a while as the TL074H, marketed 
>>> > as an "improved version", but according to the latest datasheet from 
>>> > July 2025 ( https://www.ti.com/lit/ds/symlink/tl074h.pdf ) Table 9-1 
>>> > Page 34, the new die is now being used in all of the other TL074s 
>>> > (except TL07xM):
>>> >
>>> > TL07xH - is the new version
>>> >
>>> > TL07xM - will still be the old version
>>> >
>>> > TL07xA, TL07xB, TL07xC and anything else - can be either the new or 
>>> > old version with no way of telling.
>>> >
>>> >
>>> > One part of my circuit started working incorrectly with the new 
>>> > version, but it was relying on an edge-case near phase reversal. I've 
>>> > since revised the circuit to work correctly with the new and old 
>>> > versions, but this makes me wonder how the change to this op-amp might 
>>> > effect sensitive circuits, or those creative uses we see in synths, 
>>> > audio and pedals often. It also seems like the new version has a lot 
>>> > more low frequency noise as well.
>>> >
>>> >
>>> > Thoughts?
>>> >
>>> > Mike
>>> >
>>> >
>>> >
>>> > ________________________________________________________
>>> > This is the Synth-diy mailing list
>>> > Submit email to: Synth-diy at synth-diy.org <mailto:Synth-diy at synth-diy.org>
>>> > View archive at: https://synth-diy.org/pipermail/synth-diy/
>>> > Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
>>> > Selling or trading? Use marketplace at synth-diy.org <mailto:marketplace at synth-diy.org>
>>> ________________________________________________________
>>> This is the Synth-diy mailing list
>>> Submit email to: Synth-diy at synth-diy.org <mailto:Synth-diy at synth-diy.org>
>>> View archive at: https://synth-diy.org/pipermail/synth-diy/
>>> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
>>> Selling or trading? Use marketplace at synth-diy.org <mailto:marketplace at synth-diy.org>
>>> ________________________________________________________
>>> This is the Synth-diy mailing list
>>> Submit email to: Synth-diy at synth-diy.org <mailto:Synth-diy at synth-diy.org>
>>> View archive at: https://synth-diy.org/pipermail/synth-diy/
>>> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
>>> Selling or trading? Use marketplace at synth-diy.org <mailto:marketplace at synth-diy.org>
>> ________________________________________________________
>> This is the Synth-diy mailing list
>> Submit email to: Synth-diy at synth-diy.org <mailto:Synth-diy at synth-diy.org>
>> View archive at: https://synth-diy.org/pipermail/synth-diy/
>> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
>> Selling or trading? Use marketplace at synth-diy.org <mailto:marketplace at synth-diy.org>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20250804/ccfddbe0/attachment.htm>