cspirou Posted November 7, 2016 Author Report Posted November 7, 2016 Update Song Heui: I have received an email from Song Heui to inform me that the goods are ready for shipping this Thursday. I will receive a tracking number too when they ship. For testing the pots I will just do matching at certain positions instead of checking the actual taper. I think channel matching is the most important part anyway. Any pots with horrible channel imbalance will be shipped back. This is also a reminder to pay me if you haven't done so yet. Most people have paid the base price but not the additional fees yet. If you think you have paid but I did not update the spreadsheet to credit you then let me know and I'll review my paypal info. Update TKD: I have received a quote on the stereo pots from TKD and have updated the page with real prices. I also checked on the variable potentiometers to see if there was a price difference with the variable attenuators and in most cases there was no difference or a slight increase. So better to stay with the attenuators unless someone really really needs a variable potentiometer. I will leave this open for changes until the end of this week(Nov 11) for anyone that would still like to buy TKD attenuators. Then I'll start requesting payments. Note: I am based in europe so I might change the pricing to euros as opposed to dollars.
Pars Posted November 7, 2016 Report Posted November 7, 2016 I wasn't real clear on what the difference was between a pot and an attenuator in TKD terms. Are the TKD CP-2500s that you would buy from say Percy Audio here in the states a pot or an attenuator? I am guessing attenuator judging by the way the couple that I have ohm out rotationally?I hadn't ever noticed that they offer both under the same part #/series before this was pointed out.Sent from my iPhone using Tapatalk
cspirou Posted November 7, 2016 Author Report Posted November 7, 2016 I would assume Percy Audio sells the attenuators. Here are the datasheets for the different types http://www.tkd-corp.com/products/att/pdf/cp2500as-e.pdf http://www.tkd-corp.com/products/pot/pdf/cp2500ps-e.pdf Notice the part that says 'circuit method'. The attenuator is more of a ladder circuit whereas the potentiometer is like a variable resistor. The attenuator only has an audio taper but the potentiometer can be log, linear or inverse log. Probably better to order as an attenuator to make it less likely to screw up the order. This is pretty unique to TKD. I haven't seen anyone else that does a variable attenuator like this.
GeorgeP Posted November 8, 2016 Report Posted November 8, 2016 On 11/7/2016 at 0:34 PM, Pars said: I wasn't real clear on what the difference was between a pot and an attenuator in TKD terms. Are the TKD CP-2500s that you would buy from say Percy Audio here in the states a pot or an attenuator? I am guessing attenuator judging by the way the couple that I have ohm out rotationally? I hadn't ever noticed that they offer both under the same part #/series before this was pointed out. Sent from my iPhone using Tapatalk I think it could be either based on the designation. Not sure why TKD does this. In terms of the noticeable differences though, wouldn't one of them be that the attenuator has 19 or 20 distinct dB steps (without clicks, unless the s version), while the pot doesn't have any steps?
Pars Posted November 9, 2016 Report Posted November 9, 2016 I don't recall the TKDs that I have used acting like stepped attenuators with discrete positions or attenuation levels. The ones that I have act like continuously variable pots, though they ohm out somewhat differently from a normal pot such as an Alps.Sent from my iPhone using Tapatalk
Pars Posted November 9, 2016 Report Posted November 9, 2016 From looking at the spec sheet for the attenuator product, it is configured as a semi ladder, so would act more like a pot than a stepped attenuator, which matches my observations with a DMM on these.Sent from my iPhone using Tapatalk
cspirou Posted November 15, 2016 Author Report Posted November 15, 2016 (edited) Update!!: First I want to say sorry that I haven't been on the ball with the TKD pots and updating payment info. Busy because my son was born last week!! But I will start organizing payments on that ASAP. More important though is a package arrived today. I will keep the pots for a week before shipping for testing. Shipping fees will be posted soon. If you would like to skip the testing and get your pots sooner then let me know. I will pick the pots at random and send them to you. If you have a faulty pot then you can try to deal with Hong Seui yourself or you can send them back to me. Edited November 15, 2016 by cspirou
muskyhuntr Posted November 15, 2016 Report Posted November 15, 2016 "Busy because my son was born last week!! " Congratulations! Me 1
Pars Posted November 15, 2016 Report Posted November 15, 2016 Congrats on your son! Sent from my iPhone using Tapatalk
sbelyo Posted November 15, 2016 Report Posted November 15, 2016 Congrats, take your time... And say good bye to a good nights sleep until he's out of the house lol!
cspirou Posted December 15, 2016 Author Report Posted December 15, 2016 @chiguy A little update. Most of the testing is done and it seems like I won't have to return much. I'm now organizing packing addresses and should get shipping totals to everyone soon. Message me your shipping address in a PM if you are part of this GB. TKD pots are still open in the meantime
GrindingThud Posted December 17, 2016 Report Posted December 17, 2016 Seems I missed the group buy - I still need a pair of 21 mm alpha quads (or clones) to finish my build. Any extras of either around?
cspirou Posted December 28, 2016 Author Report Posted December 28, 2016 Just want to let everyone know that the Song Heui pots fit in perfectly with the boards I received from @sbelyo. A lot of these pots measure pretty well. So unless I'm unless I'm fucking up the measurement I don't really have to return any. I still don't have everyone's shipping address but I'll be messaging you anyway. There is a small number that seem off in terms of resistance but not in terms of tracking. Here is an example of one pot Total resistance: Section 1 - 10.76k Section 2 - 10.77k Section 3 -10.70k Section 4 - 9.76k Series Resistance after turning ~45 degrees Section 1 - 10.51k Section 2 - 10.50k Section 3 -10.44k Section 4 - 9.52k The last section seems way off with 1k difference in resistance. However this is still within the 20% error tolerance specified by Song Heui so still passes their QC. But in terms of attenuation this is the result Section 1 - 32.68 dB Section 2 - 32.01 dB Section 3 - 32.28 dB Section 4 - 32.18 dB This is pretty much spot on. So does it matter if the resistance is off as long as it still attenuates fine?
Pars Posted December 28, 2016 Report Posted December 28, 2016 I would think that the attenuation is the important thing here, not the actual resistance. I could be wrong however The one shown looks to be pretty good, particularly for a cheap pot.Not sure if Justin will weigh in here as he used these for some time in his amps.Sent from my iPhone using Tapatalk
nopants Posted December 28, 2016 Report Posted December 28, 2016 I'm excited for the pots but not for unsoldering the 50k unit off kerrys board because I've been a dumbass
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