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Hit the house while it was on and I was playing it. Fried something in it.voip wrote:Did the lightning bolt actually strike the keyboard itself?? In which case you're lucky to be alive!!
In common with just about all audio and consumer gear, the Kronos is not "hardened" against such events. What else was connected to the Kronos when the lightning strike occurred?
One thing worth trying is to route the audio to the other outputs, 1 to 4, and see what happens.
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How do I check that?alland wrote:If ALL outputs behave similarly (including headphones, L/R, Individual 1-4) then issue is probably on Jack board (KLM 3005).
This can be related to "Mute All" functionality that mutes (kind a shorts) all outputs until Power is Good when turning Kronos on - to avoid pops and noise.
Mute All functionality depends directly on two signals from Power Unit - that could be also easily checked - "Standby +5" and "Power Good" - standard ATX power unit signals.
Warranty does not cover damage caused externally. Lightning, floods, dropped etc. would not be covered by a warranty. Insurance may cover it if you have a policy in place.alland wrote:1) You cannot check that without opening keyboard. If you have valid warranty and reasonable ways to get your board repaired under warranty, go there.
alland wrote:1) You cannot check that without opening keyboard. If you have valid warranty and reasonable ways to get your board repaired under warranty, go there.
2) If you want do it yourself and on your own responsibility then
a) Download Korg Kronos Service manual, easily found with Google
b) Open your Kronos, study Kronos schematic and determine where to measure voltages - there are two versions on Audio Jack boards, one of them having additronal "Mute buffer" unit. Audio Jack module to study is KLM-3005. There should be special two wire bundle coming from Power unit (PSU) with +5VSTB and PowerGood signals.
c) Have voltmeter with you and check, if signals from PSU are correct (Rewer generic ATX power supply reference for correct values but +5Vstb shluld be +5V all times when Power unit plugged in, Power Good must go from 0 to +5 when Power Supply swiched on and all output voltages are at their respective levels.
d) If PSU is not giving correct signals, repair/order new
e) If PSU gives correct signals then investigate Mute All chain on KLM-3005. If it has special Mute Buffer (KLM 3167) check its functioning (purpose is just to repeat and amplify Power OK signal)
f) Check Mute All switching transistor (Q606). In standby (Kronos not switched on) its collector (also called signal "Mute_A") must have positive voltage (that opens all muting trasistors that will short all audio signal output paths). Iw Power OK signal comes to +5 after switching Kronos on, the mute switch transistor Q606 closes, its collector (and Mute_A signal) comes to zero and even negative that closes all shorting mute transistors. Possible reason with your problem is that Mute_A is not getting zero/negative enough causing "partial muting" of your sound in all channels.
My Kronos and Kronos Service manual v2.0 (can be downloaded from https://www.synthxl.com/korg-kronos/) says:mkeschinger wrote:You mentioned the 3005. That is the digital out board. The audio jack is 3006. Is that a typo or does the digital out transmit to the audio out? Which I suppose would make sense.. Just want to clarify. There is no warranty left on the keyboard and the insurance is covering a new one. BUT I don't mind the idea of fixing this one on my own. The repair place couldn't do it, because they need to use new parts and there aren't any. But I can use used parts or replace transistors, if they are available.
Thanks you!
Weird. ok. The manual I was looking at had 3005 (d-Jack) on page 7- the parts list page. SOrry about that. I will check out page 8 right now!alland wrote:My Kronos and Kronos Service manual v2.0 (can be downloaded from https://www.synthxl.com/korg-kronos/) says:mkeschinger wrote:You mentioned the 3005. That is the digital out board. The audio jack is 3006. Is that a typo or does the digital out transmit to the audio out? Which I suppose would make sense.. Just want to clarify. There is no warranty left on the keyboard and the insurance is covering a new one. BUT I don't mind the idea of fixing this one on my own. The repair place couldn't do it, because they need to use new parts and there aren't any. But I can use used parts or replace transistors, if they are available.
Thanks you!
1) KLM-3005 is analog output (pages 20/21) that has Mute_All circuitry.
2) KLM-3006 is digital output and is not relevant in this topic (controls MIDI, SP/DIF, keybed and other I/O)
3) Both KLM-3005 and KLM-3006 gets their data from KLM-3002 (refer to block diagram on page
Thanks again!okmkeschinger wrote:Weird. ok. The manual I was looking at had 3005 (d-Jack) on page 7- the parts list page. SOrry about that. I will check out page 8 right now!alland wrote:My Kronos and Kronos Service manual v2.0 (can be downloaded from https://www.synthxl.com/korg-kronos/) says:mkeschinger wrote:You mentioned the 3005. That is the digital out board. The audio jack is 3006. Is that a typo or does the digital out transmit to the audio out? Which I suppose would make sense.. Just want to clarify. There is no warranty left on the keyboard and the insurance is covering a new one. BUT I don't mind the idea of fixing this one on my own. The repair place couldn't do it, because they need to use new parts and there aren't any. But I can use used parts or replace transistors, if they are available.
Thanks you!
1) KLM-3005 is analog output (pages 20/21) that has Mute_All circuitry.
2) KLM-3006 is digital output and is not relevant in this topic (controls MIDI, SP/DIF, keybed and other I/O)
3) Both KLM-3005 and KLM-3006 gets their data from KLM-3002 (refer to block diagram on page
Thanks!Yeah, saw that right away. Same with the circuit boards. Quick question on that though, will the older boards work in a k2? For example 3005 in a K2?KK wrote:Another important thing to consider is that the PCB part numbers in a K2 are NOT the same as the ones listed in the service manual (which were for earlier Kronos models). So you won't find a KLM-3305 in a K2. Instead the K2 PCMs are numbered like KLM-3360, KLM-3361, etc. This so that you don't order or buy a PCB that might not work in your unit.
I do not understand, what signals you are describing - just +5 and +12? If so, then those voltages seem to be good.mkeschinger wrote:Looks like we have 0 when plugged in but not turned on and then +5.03 like we should and it goes to 11.99 for the 12v at the 12v connection on 3005. Is there enough of a tolerance for that? I will check out the mute chain next. At least the haystack is getting smaller right?
