Parallel Crystals

Audioguru again

Joined Oct 21, 2019
In parallel, each crystal would try to oscillate at its own slightly different frequency.
A crystal oscillator circuit provides very good stability.
Oh, unless you build it on a solderless breadboard which picks up all kinds of interference.

sparky 1

Joined Nov 3, 2018
As a filter the less resonant frequencies are attenuated. Well matched parallel crystals mostly have an advantage in narrow band application, the relation is not really stability per say. The signal strength regarding large natural quartz crystals have less purity. The newer type grown crystals address signal integrity preferably at the amplification stage. The Q of the resonant circuit can improves signal integrity, The crystal's ambient temperature influence being a dominant factor in frequency stability. A circuit using a precision clock can develop small errors.
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Joined May 3, 2013
If you put more than 1 xtal of the same frequency in parallel, they will initially oscillate in their own slightly different frequecies, but over time, some sort of a Mutual Synchronisation will occur and all the xtals will oscillate on a common frequency. This frequency will be between the frequency of the lowest frequency xtal and the highest freq xtal.


Joined Feb 25, 2011
I was wondering what would happen to two close coupled crystals,
I don't know how you would get them to oscillate though, would each have its own amplifier ?


Joined Apr 11, 2010
Here we go, wasting our time again.
I agree. The original question indicated a desire to increase stability. The answer was no. Asked and answered. An oven stabilized crystal was proposed as a solution to the TS problem, and a commercial or DIY solution was presented. Done.


Joined Oct 2, 2009
If you put two crystals of the same frequency in parallel they will sync to each other.
You might see a very slight shift in frequency.