LeifB60 and every other whom is interested
DC resistance Driver 1 : 6.1 Ohm
Driver 2 : 6.1 ~ 6.7 Ohm
(if you observe the photos you will see a very poor soldering + small drops of solder on the spider - 1st & 3rd photo - and maybe a scratch)
Very badly surprised if you look carefully the photos .
The polarity (luckily) is the same for both drivers.
If this is the typical Mark Audio quality it is almost waist of my money
Elias
DC resistance Driver 1 : 6.1 Ohm
Driver 2 : 6.1 ~ 6.7 Ohm
(if you observe the photos you will see a very poor soldering + small drops of solder on the spider - 1st & 3rd photo - and maybe a scratch)
Very badly surprised if you look carefully the photos .
The polarity (luckily) is the same for both drivers.
If this is the typical Mark Audio quality it is almost waist of my money
Elias
I'm sorry you received substandard elements.
I can assure you that mine are top notch quality.
The only complaint I have is that + and - are not marked.
Sad for you. Maybe you can complain about the quality at the dealer and get them replaced.
MarkAudio's polarity indicator is hard to find.
I use dbx CT2 to check polarity.
I think MarkAudio's assembly quality is better than other companies, and my CHP-90 seems to have no problems.
If you are concerned about it, why don't you have it replaced?
Incidentally, Fostex had a magnet that was out of alignment, and Scan-speak had a magnet that fell off.
I use dbx CT2 to check polarity.
I think MarkAudio's assembly quality is better than other companies, and my CHP-90 seems to have no problems.
If you are concerned about it, why don't you have it replaced?
Incidentally, Fostex had a magnet that was out of alignment, and Scan-speak had a magnet that fell off.
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I already e-mail to soundimports and I had an answer. Οbviously I don't blame them for the sloppiness of the production chain. Ι doubt if they opened the boxes they received from china. After my close and intend inspection (professional perversion 😒😒) of the drivers I left those as they were iin their box waiting "support" to examine the photos I attached (same as in my previews post). I like to believe that it is the results of "cutting the cost" for this driver and not the standard orientation of the company (Mark Audio)
Elias
Good that you contacted them. It is the fault of the Chinese that they are not so thorough.
Mark Audio certainly does not want to ruin their reputation.
Although have seen a few mistakes lately.
You can't complain about the supplier, but of course it can happen at all levels.
Hope to get new drivers so you will be satisfied. 😉
Nandappe
my professional eye caught the imperfection (common in multi stranded conductors) that leads to partially poor joint (the left pole "+" ) .
dbx CT2 . Nice you have it . As for polarity indexing you are right ! It was tricky to see the marks on that little inclined plastic blobs.
Elias
It would be better if soundimports forwarded my e-mail to MarkAudio's production manager. It is very tricky and maybe risky to try remove with a very thin curling tongs those very tiny soldering blobs from the spider. New drivers ? Maybe is the best but will they accepted it ? At whose expense ? After how many months ?
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I am almost certain that you will be offered a new pair.
They usually respond quickly.
I haven't had any major problems with them before. They have many more pairs.
The effectiveness of having a Ser.No is that the QA department can have feedback and knows who has dealt with that part to protect the reputation of the "name" (Mark Audio).
All the pencil plans as in imperial plywood dimensions making it 19.1mm thick. I can only find 18mm. Do i need to adjust for this? Make the horizontals 2mm shorter to correct the line length.
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Pensil CHP90's plan is drawn at 18mm thickness.
For different board thicknesses, it is better matching the inner dimensions.
Bluetooth (BT) is great!!!
I use BT in the car, but this is my first time using it at home.
MP3 (256kbps) from cell phone (KYF38) and playback with BT amp and CHP90-mica(DDVP-12.5-ML).
[ Air-Recording ] Waiting in Vain / Halie Loren
Cell Phone(MP3, 256kpbs)-Bluetooth AMP-CHP90 mica
I use BT in the car, but this is my first time using it at home.
MP3 (256kbps) from cell phone (KYF38) and playback with BT amp and CHP90-mica(DDVP-12.5-ML).
[ Air-Recording ] Waiting in Vain / Halie Loren
Cell Phone(MP3, 256kpbs)-Bluetooth AMP-CHP90 mica
I think the power supply is more important than the power chip for a class-D amplifier.
Changing from a switching power supply or analog power supply to a GaN(gallium nitride) power supply can improve sound quality.
This time I used a 100W (20V, 5A) PD(power delivery) power supply.
Changing from a switching power supply or analog power supply to a GaN(gallium nitride) power supply can improve sound quality.
This time I used a 100W (20V, 5A) PD(power delivery) power supply.
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I just found a "paper" of Texas Instrument about GaN semiconductors and yes, maybe they have some benefits over MosFET semiconductors in lower power demanding applications (chargers USB Type-C). On the other hand, using SMPS for over 35 years (professionally) I know that the design of the circuit dominates. To clarify more, when there is a load that has (large) step current demand NON periodically, but the current demand is "more frequent" than the alternative current of the mains (50Hz in Europe) then a humble linear power supply with big smoothing capacitors + schottky-diodes rectifier is superb BUT it is balky + the capacitors aren't cheap. For now , in resident, I'm using almost always C-L//R-C-L//R-C filters after a SMPS when I need low ripple, BUT I don't have the charger you have, in hands "for a test ride"😉 (
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another "test ride" for the driver + amplifier + power supply combo is this
and especially at about 17:00 the "tuba"
