Denon DP80 & DP75 Owner's Thread

[matteos]

Tks ... was only happy for a while.

Immediately checked my dk-300 but it does not have metal inserts for bolts but this shared info also reminded me on such option to be considered.

Yours must be a later improved version from Denon or modified by previous owner with same concern on use of self tapping screws.

Photo of serial # of mine and metal inserts for dustcover hinges instead

Cheers.

View attachment 3259404View attachment 3259405
View attachment 3259412

Mine looks the same as yours and I did wonder about the same questions you have. I used the screws that came with, but the holes were already there and the screws fit fine.

I wonder if having these little wooden inserts help dampen the motor vibrations from the rest of the plinth. I also tried adding some sorbothane washers on top between the unit and plinth and they seemed to make no difference either.

Denon seemed to put a lot of thought into these plinths and they are very good just as they are, only different feet have really made a difference to the sound with all the things I have tried, but the stock feet are pretty good already.

Also I was able to finally track down a DK2300 that wasn’t being sold as a combo with drive unit and arm, it was incredibly cheap! But also looks kind of beaten up in the pictures and might need a re-veneer. I think it’s going to be too big for my shelf (I’m very limited on space for gear) as it’s also wider as well as deeper than the DK-300, but having two arms available is going to be sweet.

 

[MX117.MC7150]

0.02% wow and flutters by android rpm app that my 2nd refurbished dp-80 including new bearing change demonstrates or 0.2% rpm error which is 4x better ? Cheers.

View attachment 3261288

I was talking rpm, which I neglected to state. Also, though I've forgotten the adjustment pot numbers(), You can adjust the speed using same.

 

[richardloh]

I was talking rpm, which I neglected to state. Also, though I've forgotten the adjustment pot numbers(), You can adjust the speed using same.

Nice ! My almost fully refurbished one is 4x higher at almost 0.8% rpm error via android rpm speed and wow app

 

[adnick]

Nice ! My almost fully refurbished one is 4x higher at almost 0.8% rpm error via android rpm speed and wow app

Is that actually tested with needle down, playing an album ? Also have you tested it with a strobe light, or stop watch, I’d certainly double check before tr to fix a problem that’s presented by a single phone app…..

Just some thoughts,

Andy

 

[richardloh]

Is that actually tested with needle down, playing an album ? Also have you tested it with a strobe light, or stop watch, I’d certainly double check before tr to fix a problem that’s presented by a single phone app…..

Just some thoughts,

Andy

Hi Andy,

Thanks but sorry for the confusion.

I am trying to fix the 1st dp-80 which shows wow % of 0.8% for 33.3 rpm when best adjusted at variable mode while 45 rpm looks ok at 0.03% .. locked modes are worse even after replacing the obviously defective semi fixed 5kohm resistors that seems to be a common issue.

Desperate swap-all-I-can repair is not the 2nd refurbished unit that shows wow % of 0.02% for both 33.3 rpm and 45 rpm at both locked and variable mode that is distinctly much more stable for 33.3 rpm of the 1st unit.

Cheers.

PS: All wow % error measurement via rpm wow app are without lp being dragged by needle .. I had not gotten that far to set up the available dk300 plinth and tonearms

 

[richardloh]

1st step on plinth refurbishment by external contractor ... 4 armboards plugged with solid teak.

Plinth also brought to contractor for the following:

1. Undercut into plinth to house kashimura 35VA 230-240v to 100v transformer

2. 3X M5 clearance mounting holes for SS 90mm bolts

3. Revinyl damaged black vanity under plinth

More photos to follow till last step of 2k automotive high gloss paint and finished plinth .. not into wood and typical black finish.

Cheers.

 

[russtafarian]

Howdy folks. I just discovered this awesome thread.

Here's my "DP160".



Russ

 

[matteos]

Nice setup! Tell us more about those awesome looking plinths, are they custom?

 

[richardloh]

Hi Andy,

Thanks but sorry for the confusion.

I am trying to fix the 1st dp-80 which shows wow % of 0.8% for 33.3 rpm when best adjusted at variable mode while 45 rpm looks ok at 0.03% .. locked modes are worse even after replacing the obviously defective semi fixed 5kohm resistors that seems to be a common issue.

Desperate swap-all-I-can repair is not the 2nd refurbished unit that shows wow % of 0.02% for both 33.3 rpm and 45 rpm at both locked and variable mode that is distinctly much more stable for 33.3 rpm of the 1st unit.

Cheers.

PS: All wow % error measurement via rpm wow app are without lp being dragged by needle .. I had not gotten that far to set up the available dk300 plinth and tonearms

Believe the resolution of my 1st dp-80 with high wow % had taken a positive turn in this extended journey

While waiting for more Denon parts to arrived, complete pcb assemblies of reportedly later production year with less potential failures due to lead oxdisation from a working dp-80 was made available and bid was successful at a good price .. with added advantage of much lower shipping due to weight.

Wish me luck in now updated plan to do board swap instead of component swap but yes, will order the ebay's recap kit with 6 transistors for ku-263

Cheers.



☆Product Overview
We are offering for sale a set of peripheral drive parts and circuit boards for the DENON phono motor DP-80.
This item was removed from a used DP-80 in good working order. Everything in the picture is included.
Judging from the serial number, it appears to be a late production item.
In early production products, the leads of the small-signal molded transistors were corroded and blackened by migration, causing frequent control problems over time.
It appears that later production products have been improved through a review of the components mounted on the board and semiconductors.
This board uses transistors that are different from those used in initial production products, so you can rest assured that there will be no blackening as mentioned above.
For those who regularly use the initial production product, how about using this for future maintenance?

☆Drive unit specifications
1) Perhaps because of the short operating time, it also comes with a bright neon lamp that has been kept in its original condition.
2) The lead wire for the normal⇔variable selector switch will be removed and attached. The selector switch is not included.
3) The lead wires for the volume for fine adjustment of rotation when switching between variable modes will be removed and attached. Volume is not included.
4) In order to remove the phono motor from the main body, some of the lead wires have been cut off at the connector connection part.
5) Since it was in working order, I don't think there will be any problems with the operation of the circuit boards. However, when replacing it, it will be necessary to check for hairline cracks in the circuit board pattern, swelling due to deterioration of the electrolytic capacitor, and the rotation using a semi-fixed resistor for rotation adjustment at 33/45 rpm.
6) Screws for removal will also be included.

 

[Mark 1234]

Believe the resolution of my 1st dp-80 with high wow % had taken a positive turn in this extended journey

While waiting for more Denon parts to arrived, complete pcb assemblies of reportedly later production year with less potential failures due to lead oxdisation from a working dp-80 was made available and bid was successful at a good price .. with added advantage of much lower shipping due to weight.

Wish me luck in now updated plan to do board swap instead of component swap but yes, will order the ebay's recap kit with 6 transistors for ku-263

Cheers.

View attachment 3266111

☆Product Overview
We are offering for sale a set of peripheral drive parts and circuit boards for the DENON phono motor DP-80.
This item was removed from a used DP-80 in good working order. Everything in the picture is included.
Judging from the serial number, it appears to be a late production item.
In early production products, the leads of the small-signal molded transistors were corroded and blackened by migration, causing frequent control problems over time.
It appears that later production products have been improved through a review of the components mounted on the board and semiconductors.
This board uses transistors that are different from those used in initial production products, so you can rest assured that there will be no blackening as mentioned above.
For those who regularly use the initial production product, how about using this for future maintenance?

☆Drive unit specifications
1) Perhaps because of the short operating time, it also comes with a bright neon lamp that has been kept in its original condition.
2) The lead wire for the normal⇔variable selector switch will be removed and attached. The selector switch is not included.
3) The lead wires for the volume for fine adjustment of rotation when switching between variable modes will be removed and attached. Volume is not included.
4) In order to remove the phono motor from the main body, some of the lead wires have been cut off at the connector connection part.
5) Since it was in working order, I don't think there will be any problems with the operation of the circuit boards. However, when replacing it, it will be necessary to check for hairline cracks in the circuit board pattern, swelling due to deterioration of the electrolytic capacitor, and the rotation using a semi-fixed resistor for rotation adjustment at 33/45 rpm.
6) Screws for removal will also be included.

If you swap one board at a time from your working one onto the one that is off you can narrow it down significantly.

 

[claneg]

It appears that later production products have been improved through a review of the components mounted on the board and semiconductors.
This board uses transistors that are different from those used in initial production products, so you can rest assured that there will be no blackening as mentioned above.

When you get the boards, please tell us the substituted transitors type. It would be useful for all DP80/75 owners.

 

[richardloh]

When you get the boards, please tell us the substituted transitors type. It would be useful for all DP80/75 owners.

I will certainly do so. Cheers.

 

[clintalloy]

I’ve found there’s quite a few armboards for DK plinths on Jauce. I have a few coming over on the slowboat from Japan. There’s a lot of fees with that site, but there’s definitely some to be found there.

You can also make one reasonably easily. This is how I made one because I couldn’t find one to buy. I made it out of 2 maple boards and a piece of walnut. I just bought three pieces of wood that were pretty much cut to size from eBay and glued them together with clamps, cut a little off the length and then I measured the tonearm hole and drilled it in the right spot with a correct sized hole saw. These were the dimensions I bought off eBay. Cost about $30 for all of it.

1 sheet of walnut - 12” L x 6” W x 1/4” H
1 sheet of maple - 12” L x 6” W x 1/2” H
1 sheet of maple - 12” L x 5” W x 1/2” H

The last sheet of maple was 1 inch narrower than the other two. These arm boards have a slope on both sides so you can position them in the plinth underneath the mounted motor unit, so once I glued together I planed the wood to make a slope, the narrower piece gave me less to chop off.

Only other thing to remember is to drill a much bigger hole in the bottom sheet of wood before you glue them all together (1.5” - 2” inches wide ) where the tonearm hole will eventually be to make it easier to attach the tonearm. I’m pretty crap at woodwork (as you can probably tell), but this has definitely worked well enough for my needs. I used Tung oil as a finish because I’m fairly lazy and it’s really easy to use.
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View attachment 3244965

Cool, thanks for this. I did find a couple on Buyee (same kind of thing as Jauce) -- I have ordered one and will see if it fits OK. It might be from a DK-110 originally.

Anyway, I will probably make a 3D model for this at some point and share it here or on one of the 3D sharing platforms. It won't be too hard, and can then be modified to work with different tonearm geometries. Even if you don't have a 3D printer, you can get things printed online for like $20 - $50.

 

[clintalloy]

Glad and relieved to share that 2nd dp-80 just received today from Japan which is reportedly "beautiful" and maintained indeed looks minty and runs well even in quartz lock with wows and flutters at 0.02% for both 45 rpm and more importantly 33.3 rpm.

Will proceed with the same ceramic coating and also neoprene foam replacement nicely shared by Matteos.

Cheers.

View attachment 3259509View attachment 3259510View attachment 3259511

what turntable speed app are you using here?

thx --g

 

[richardloh]

what turntable speed app are you using here?

thx --g

Hi Clint, Samsung android phone user and using this one:

RPM Speed & Wow - Apps on Google Play

Calculate speed and speed variations of your turntable.

play.google.com

Cheers.

 

[matteos]

Cool, thanks for this. I did find a couple on Buyee (same kind of thing as Jauce) -- I have ordered one and will see if it fits OK. It might be from a DK-110 originally.

Anyway, I will probably make a 3D model for this at some point and share it here or on one of the 3D sharing platforms. It won't be too hard, and can then be modified to work with different tonearm geometries. Even if you don't have a 3D printer, you can get things printed online for like $20 - $50.

For sure if you do a 3D model it would be awesome to drop the plans here. I imagine you can print with different kinds of materials? Would be interesting to see how well they can tame vibrations.

I was in IKEA the other day and bought this… Nabbfisk. It’s so close to the same dimensions, probably about 1/8” or so too wide to just drop in. Obviously not as deep, but I reckon could be modified quite easily for that. It’s already got the slopes on each side ready to go.

 

[russtafarian]

Nice setup! Tell us more about those awesome looking plinths, are they custom?

The DP-80 plinths were put together by a friend of mine who builds audio gear. He works with a cabinet builder for his speaker cabinets and amplifier chassis. He took a DK300 plinth to the cabinet builder and asked him to replicate it including the DP-80 cutout. Both plinths are made of stacked Baltic birch. The lefthand plinth is four inches high with walnut veneer. The other is six inches high with burled walnut veneer.

 

[richardloh]

Hi Matteo,

Bought the neoprene foam and will do so likewise for the 2nd dp-80 .. will compare if discernible from the window foam used for platter from limping 1st unit to decide .. tks !

On the footers shared, I held back as my preference is always with adjustability which they are without.

Chanced on some adjustable 43-75mm footers (NOT gold version ! ) used in furnitures that are cheap at usd15 drilled to M6 since not audio related sale and getting thick sorbathane discs from ebay that are quite expensive to me to mirror the mnpctech adjustable footers that I bought for my dp-47f.

Mnpctech's dp80 footers are also without adjustability and customisation will likely cost even more than usd259 for height suitable ones for vpi which is too much for me.

Cheers.

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Decided that while ebay's sorbathane discs will no doubt be predictably better, thickness of 12.7mm means probably stacked ones needed for 3" height required or usd80 including shipping to Singapore that will be too much for my experiment for adjustable footers to avoid usd259 Mnpctech ones:

4 VIBRATION ISOLATION RING FEET 1.5" 38mm DIA .5"H 50D SORBOGEL TURNTABLE Q NS | eBay

Vibration absorbing sorbogel rings. 1/2" (12.7mm) high but squish down with weight. 1/2" (12.7mm) hole in center. 50D density. You will receive 4 feet in a plastic bag. They do not include adhesive but are sticky or you can use spray on adhesive or superglue.

www.ebay.com

Proceeded instead with the usd5 ones of various thickness non branded and who-knows what rubber material used ones below:
【淘宝】限时每300减40 https://m.tb.cn/h.gkKbsxyWfr1YdiO?tk=2sQd3WuJ6KN CZ0000 「高弹橡胶圆形减震垫冲床机器防震防撞耐磨带孔螺丝风机设备垫片圈」
点击链接直接打开 或者 淘宝搜索直接打开

Meanwhile, received the "furniture" footers and pleased with them for the quality and solid construction to order some cheap usd5 worth of leaded fishing shots to fill up their cavities but unable to try them out as plinth is at carpentry workshop for modification.

Cheers.

 

[richardloh]

Decided that while ebay's sorbathane discs will no doubt be predictably better, thickness of 12.7mm means probably stacked ones needed for 3" height required or usd80 including shipping to Singapore that will be too much for my experiment for adjustable footers to avoid usd259 Mnpctech ones:

4 VIBRATION ISOLATION RING FEET 1.5" 38mm DIA .5"H 50D SORBOGEL TURNTABLE Q NS | eBay

Vibration absorbing sorbogel rings. 1/2" (12.7mm) high but squish down with weight. 1/2" (12.7mm) hole in center. 50D density. You will receive 4 feet in a plastic bag. They do not include adhesive but are sticky or you can use spray on adhesive or superglue.

www.ebay.com

Proceeded instead with the usd5 ones of various thickness non branded and who-knows what rubber material used ones below:
【淘宝】限时每300减40 https://m.tb.cn/h.gkKbsxyWfr1YdiO?tk=2sQd3WuJ6KN CZ0000 「高弹橡胶圆形减震垫冲床机器防震防撞耐磨带孔螺丝风机设备垫片圈」
点击链接直接打开 或者 淘宝搜索直接打开

Meanwhile, received the "furniture" footers and pleased with them for the quality and solid construction to order some cheap usd5 worth of leaded fishing shots to fill up their cavities but unable to try them out as plinth is at carpentry workshop for modification.

Cheers.

View attachment 3268685View attachment 3268686View attachment 3268689

Very happy this evening with diy and cost effective, fully adjustable "furniture" footers at usd10 for 4 pieces for pending refurbished dp-80 plinth, lined with double layered groundzero damping material I happened to have throughout except needed thread section .. each is now about 200g since loaded with cheapest usd6 lead balls I can find that are used for fishing.

Await rubberised rings of 10, 20 and 30mm thick at usd5 to determine what is for final product to mirror stock 3" height

 

[matteos]

The DP-80 plinths were put together by a friend of mine who builds audio gear. He works with a cabinet builder for his speaker cabinets and amplifier chassis. He took a DK300 plinth to the cabinet builder and asked him to replicate it including the DP-80 cutout. Both plinths are made of stacked Baltic birch. The lefthand plinth is four inches high with walnut veneer. The other is six inches high with burled walnut veneer.

They look awesome, especially the finish. The veneer on mine doesn’t look so great 40+ years later.

Very happy this evening with diy and cost effective, fully adjustable "furniture" footers at usd10 for 4 pieces for pending refurbished dp-80 plinth, lined with double layered groundzero damping material I happened to have throughout except needed thread section .. each is now about 200g since loaded with cheapest usd6 lead balls I can find that are used for fishing.

Await rubberised rings of 10, 20 and 30mm thick at usd5 to determine what is for final product to mirror stock 3" height

View attachment 3268922
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Interesting concept, let me know how they turn out, are you going to further damp the lead with silicon or sand or something like that?

My DK2300 has finally arrived, I really want to install it, but it’s too big for my shelf, very heavy too.