atc 75-150
hello they sell me some atc sm 75-150 st and the measurements with the multimeter are 10 ohm is it feasible or are they already widely used?
hello they sell me some atc sm 75-150 st and the measurements with the multimeter are 10 ohm is it feasible or are they already widely used?
mbrennwa,
FYI, my interpretation of miguel's words is/are that he has purchased a pair of sm 75-150st from ATC and is now wondering why they measure out at 10 ohms ( dcr ).
- IOW, ( to paraphrase someone else's thought-balloons ) I believe he wants to know if the lower than expected dcr measurement implies that they sold him used goods?
That's my take // which ( looking behind the curtain ) all-in-all helps explain why it's taken 4 years to get to this point in a so called DIY forum.
🙂
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atc 75-150
the 16 ohm recone kit is almost like the new speakers.
They sell me some but they measure 10 ohm I think it's a little low value
the 16 ohm recone kit is almost like the new speakers.
They sell me some but they measure 10 ohm I think it's a little low value
Unfortunately ATC does not seem to specify the RDC in their datasheets of the SM75-150, so we cannot compare the 10 Ohm reading with the ATC specs. However, here is an impedance curve I measured with a 16 Ohm SM75-150-STD: http://hifibau.ch/wp-content/uploads/2016/02/lowpass_atcSM75-150_hiba.png --> this is consistent with a DCR close to 10 Ohm. This might suggest that miguelnoda has 16 Ohm units.
miguelnoda: please check the markings on the back of your drivers. Maybe post some photos.
miguelnoda: please check the markings on the back of your drivers. Maybe post some photos.
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You cannot buy these drivers "new". When I bought the recone kit, it was quite a bit cheaper than the typical ebay prices for second-hand drivers.
The DCR value is different from the "nominal impedance" value. The RDC can well be 10 Ohm for a "nominal 16 Ohm" driver.
That sounds about right for a DCR. 8 Ohm drivers usually have a DCR around 6 Ohms; 4 Ohm drivers DCR around 3 Ohms...very generalized for sure. 10 Ohms DCR for a 16 Ohm driver is about what I would expect not knowing anything else about it.
Ok, I double-checked my SM75-150-SUPER. They are 16 Ohm units (not 8 Ohm as stated before). The DCR is 9.8 Ohm.
miguelnoda: I am pretty sure you have the 16 Ohm version.
miguelnoda: I am pretty sure you have the 16 Ohm version.
Atc sm75-150 8ohm
How can I check you means to know if they are in perfect condition apart from the dcr resistance
How can I check you means to know if they are in perfect condition apart from the dcr resistance
Measure the impedance curve. Measure SPL response. Measure harmonic distortion.
What is the problem you are trying to solve?
Are you repairing an old speaker or building a new one?
If there are bad/dry components, fresh modern ones will improve sound.
If they are working properly, "Audiophile"/snake oil/NASA type etc. ones won´t improve anything.
Those are passive components and can´t add which was not there to begin with.
Are you repairing an old speaker or building a new one?
If there are bad/dry components, fresh modern ones will improve sound.
If they are working properly, "Audiophile"/snake oil/NASA type etc. ones won´t improve anything.
Those are passive components and can´t add which was not there to begin with.