Yep, that’s the stuff I don’t want to wreck!
Denon DP80 & DP75 Owner's Thread
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Kit Carson
Active Member
Also seen a few Denon DP-75/80 used without plinths. If the DP-100 was any indication a plinth was an important part of the overall design. Denon offered professional consoles for the DP-80 and the prior model DP-6000/7000 used in broadcasting and recording studios. For some it might be overkill but I have my DP-75 mounted in a VPI suspended plinth sitting on a large Target wall shelf, total weight of table/tonearm/plinth is about 75lbs. A heard of elephants could run thru the house and the table wouldn't miss a beat.
Kit Carson
Active Member
matteos might want to consider masking tape over magnetic strip when working on/cleaning platter
Some painters tape would be a good idea, you’re right.
richardloh
Active Member
Hey Crustex, did you managed to fix the issue ? I recapped my DP-80 just purchased and did had transistors reversed soldered that resulted in high speed rotation and had thought all ok when resoldered the transistors correctly.
The issue I have now is that 45rpm runs perfectly fine in both quartz locked and variable modes but at 33rpm, it is not stable and it has the same mentioned mechanical sounding knocking/rumbling issue except that it happens at both quartz lock and variable in 33rpm which is critical for usual playback.
Appreciate if you (and anyone) can share how I can fixed this but will attempt to adjust/deoxit VR1 as Mark had advised
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richardloh
Active Member
Update:
45rpm at both quartz lock and variable remain spot on and WHISPER QUIET .. deoxit VR1 for 33rpm and adjustment shows variation but remains unstable and mechanical-like knocking sound remains .. variable is slightly better but still drifts and very unlike 45rpm in both modes. I suppose the key concern of knocking sound at slower 33 rpm at both quartz locked and variable is due to unstable speed and did check that tape head is certainly not rubbing ... I did noticed that pressing on the double layer platter diagonally across with reworked weathershield foams did knock the 2 layers of the platter.
Will let it run at 33rpm quartz locked overnite and check it again in about 7-8hrs.
Will write to request ebay seller of caps and transistors to get replacement transistors to replace in case faulty due to initial wrong orientation and call it a day if not fixed as shipping this out to expert technicians in USA/Japan with expected hundreds of usd with uncertainties is beyond my means.
Fortunately, I did not proceed with automotive respraying of dk300 plinth or ordered Acoustech console plinth for a deeper pit and hope the 3 tonearms bought for this dp-80 will be sold off without too much loss as they are in great cosmetic condition and were ones of those lower priced "good buys".
Hope to update in time with better news
PS: No sense to run at variable for usual 33rpm nor to proceed with plinth with such notable stabiliity issue .. and this knocking sound can only be very very bad for sound quality
45rpm at both quartz lock and variable remain spot on and WHISPER QUIET .. deoxit VR1 for 33rpm and adjustment shows variation but remains unstable and mechanical-like knocking sound remains .. variable is slightly better but still drifts and very unlike 45rpm in both modes. I suppose the key concern of knocking sound at slower 33 rpm at both quartz locked and variable is due to unstable speed and did check that tape head is certainly not rubbing ... I did noticed that pressing on the double layer platter diagonally across with reworked weathershield foams did knock the 2 layers of the platter.
Will let it run at 33rpm quartz locked overnite and check it again in about 7-8hrs.
Will write to request ebay seller of caps and transistors to get replacement transistors to replace in case faulty due to initial wrong orientation and call it a day if not fixed as shipping this out to expert technicians in USA/Japan with expected hundreds of usd with uncertainties is beyond my means.
Fortunately, I did not proceed with automotive respraying of dk300 plinth or ordered Acoustech console plinth for a deeper pit and hope the 3 tonearms bought for this dp-80 will be sold off without too much loss as they are in great cosmetic condition and were ones of those lower priced "good buys".
Hope to update in time with better news
PS: No sense to run at variable for usual 33rpm nor to proceed with plinth with such notable stabiliity issue .. and this knocking sound can only be very very bad for sound quality
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richardloh
Active Member
No big surprise using android rpm app
This knocking sound only obvious at 33rpm for both quartz locked and variable .. any thought?? Thanks !
This knocking sound only obvious at 33rpm for both quartz locked and variable .. any thought?? Thanks !
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richardloh
Active Member
Hey Mark, I stupidly did not test out the speed with rpm app when I first received it and it was uncontrolled high speed due to wrong orientation of the 6 new transistors on the KU 263 pcba and then this latest 33 rpm instability and more critically knocking noise issues. Cheers.
richardloh
Active Member
Yes, I am in Singapore where there are no known technicians to me that can troubleshoot and fix such a complex turntable with proper lab equipment and workbench ... just like me.
Hence at the brink of giving up this project ... ebay seller will nicely send new replacement transistors which I can only remotely hope issue is due to them being damaged when my repair technician soldered them in wrong orientation.
I searched www and it seems that only member Crustex here had reported same knocking/rumbling sound of dp-80 with rpm instability issue albeit his case was when in quartz lock while my case is in both quartz lock and variable modes.
Btw, check this morning shows same whisper quiet operation at 45rpm while taking a bit of time to stabilise while 33 rpm is still plagued by same issue of instability and knocking/rumbling sound which I cannot determine its source.
Cheers.
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richardloh
Active Member
Googled a bit more over at site:co.jp and it seems that my issue on 45rpm being fine and 33rpm being unstable with mechanical like knocking/rumbling/rubbing noise is not unique.
2 or 3 owners/repair shops reported the same but unfortunately, no specific component had been identified and a barrage of components were replaced as fix ... bad news so far then.
Cheers.
2 or 3 owners/repair shops reported the same but unfortunately, no specific component had been identified and a barrage of components were replaced as fix ... bad news so far then.
Cheers.
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richardloh
Active Member
Read more thoroughly on identical 45rpm being ok while 33rpm is unstable and will get new semi variable VR1 and VR2 resistors (Nihon Denki Copal Electronic Semi-Fixed Resistor CT-6EP 1k Ohm while svc manual stated 10k ohm type .. dunno if typo and ordered both 1k and 10k ohm) that this owner elude to being the key fix since all capacitors had been replaced while continue with the new replacement transistors from ebay sellers does not fix the unstable 33 rpm issue .. especially since with detailed instructions on adjustment without scope.
Will persist as long as within my means and hope with such possible fix(es) found before giving up to part out this dp-80 since had also not seen any being available else getting working KU-263 or KU-264 could have been a viable trial .. the somewhat rocky journey continues but guess this update is a bit of good news
Cheers.
Link here:
Will persist as long as within my means and hope with such possible fix(es) found before giving up to part out this dp-80 since had also not seen any being available else getting working KU-263 or KU-264 could have been a viable trial .. the somewhat rocky journey continues but guess this update is a bit of good news
Cheers.
Link here:
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richardloh
Active Member
Btw, not sure of validity as mine was done by technician but anyone doing recapping may wish to consider several japanese repairs from searching on site:co.jp that highlighted C12 pcba silkscreen marking on one of the pcba is erroneous from actual original orientation.
I will certainly check on mine and follow suit and anyone who had done recapping may wish to share for confirmation to help future seemingly mandatory recapping attempt especially common leakage on 250v rated capacitor that some uprated even to 500v ones. Cheers.
I will certainly check on mine and follow suit and anyone who had done recapping may wish to share for confirmation to help future seemingly mandatory recapping attempt especially common leakage on 250v rated capacitor that some uprated even to 500v ones. Cheers.
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richardloh
Active Member
More easily available thru hole 10uf 400v works fine too for the commonly leaked 4.7uf 250v one who successfully repaired his dp-80 on other issues. Cheers.
richardloh
Active Member
Hi Matteos, How is the DP-75 holding up against the DP-80 or you feels that the DP-80 is still noticably sounding better in the same set up of plinth, TA and cart ?
I am still waiting for a fresh batch of transistors to arrived while having received replacement semi fixed VRs to try solve my unstable 33 rpm issue with the dp-80. However, I chanced upon a stock dp-75 with selectable localn240v voltage at usd500 and hence wish to be advised if it will be a backup plan if dp-80 still remains unrepairable. A host of bought TAs, cartridges and available used dk-300 is a bit of fix for me to give up now on this dp80/75 project.
TIA and cheers.
Good question! I spent a lot of time comparing stuff with these turntables and the plinths/feet etc.
So I had redone the platter on the 75 with window sealer foam and I redid the platter on the 80 with sorbothane. And the 80 sounded better, I took apart the 75 platter and found the foam I had used was crap and it had flattened and was useless. I replaced this with “audio” foam from Amazon… Now the 75 sounds much better, even better than the 80. So I took the Sorbothane out of the 80 plinth and redid it with the same foam, now it sounds better and pretty much the same really as the 75. With same plinth, arm etc the sound is not much different. The 80 is a little more satisfying though because it has power like my Lenco, hard to slow down the platter holding a cleaning brush very firmly on a spinning record, and that is quite nice!
So, for me sorbothane is out. It sounds great in a lot of ways, super quiet, black background but it robs something from the presentation I think, and after a while I lose interest in the music.
As for plinths. The DK-300 is better than the earlier plain wood ones like the DK-2000. Just a blacker background. I’m now in the hunt for a DK-2300 which will be end game plinth for this (maybe reveneer).
For plinth feet I swapped a lot of stuff in that I have (I used a thread adaptor to convert the size differences in the mounting bolts). I tried out the ones in the picture, including these isoacoustic ones (meant for speakers but I have them lying around). Hands down the best feet are the ones on the right (black is plastidip because the feet are so shiny as to look bad). Anyway, I got these off eBay. They are maglev and have three ball bearings in a cup at the top. I do recommend these. My kids jump really hard up and down next to this turntable and nothing, they really isolate it, better than the isoacoustic (although to be fair, these ones are designed for more weight.. and speakers).
So this is what I’ve finally landed on. The 75 is absolutely great and if you have one there’s no real need to upgrade to the 80. In fact if you have a US DP-75, it’s prob better to keep it than have the hassle of the transformer.
Once I find a 2300 plinth, the 80 is going on that and I suppose I’ll keep the 75 as a backup, or maybe sell.
Also the Denon 401 arm is a really good arm, and fits very well on these.
.
So I had redone the platter on the 75 with window sealer foam and I redid the platter on the 80 with sorbothane. And the 80 sounded better, I took apart the 75 platter and found the foam I had used was crap and it had flattened and was useless. I replaced this with “audio” foam from Amazon… Now the 75 sounds much better, even better than the 80. So I took the Sorbothane out of the 80 plinth and redid it with the same foam, now it sounds better and pretty much the same really as the 75. With same plinth, arm etc the sound is not much different. The 80 is a little more satisfying though because it has power like my Lenco, hard to slow down the platter holding a cleaning brush very firmly on a spinning record, and that is quite nice!
So, for me sorbothane is out. It sounds great in a lot of ways, super quiet, black background but it robs something from the presentation I think, and after a while I lose interest in the music.
As for plinths. The DK-300 is better than the earlier plain wood ones like the DK-2000. Just a blacker background. I’m now in the hunt for a DK-2300 which will be end game plinth for this (maybe reveneer).
For plinth feet I swapped a lot of stuff in that I have (I used a thread adaptor to convert the size differences in the mounting bolts). I tried out the ones in the picture, including these isoacoustic ones (meant for speakers but I have them lying around). Hands down the best feet are the ones on the right (black is plastidip because the feet are so shiny as to look bad). Anyway, I got these off eBay. They are maglev and have three ball bearings in a cup at the top. I do recommend these. My kids jump really hard up and down next to this turntable and nothing, they really isolate it, better than the isoacoustic (although to be fair, these ones are designed for more weight.. and speakers).
So this is what I’ve finally landed on. The 75 is absolutely great and if you have one there’s no real need to upgrade to the 80. In fact if you have a US DP-75, it’s prob better to keep it than have the hassle of the transformer.
Once I find a 2300 plinth, the 80 is going on that and I suppose I’ll keep the 75 as a backup, or maybe sell.
Also the Denon 401 arm is a really good arm, and fits very well on these.
.
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My DP-2000 sometimes has a knocking sound the first minute or so after turning it on. The speed isn't right during that time either. Shortly after it goes away and the speed is dead on. I kinda got used to it at this point and have been thinking maybe one day I'll find another DP-2000 unit on the cheap to replace it. Wonder if it's the same thing?
Also wondering whether or not a DP-75/80 would fit in the same DP2550 plinth I have.
Yep. Solid wood (plywood for the most part but still) with crappy fake vinyl veneer on it. Here's a photo of it after I stripped it
before re-veneering with real walnut veneer. Because the plinth looks gorgeous now I'm kinda hoping I can 'upgrade' to a DP-75/80 at some point without needing a new plinth.
Finished product:
