AudioNervosa

Systemic Development => Digital Audio Devices => Topic started by: HAL on December 17, 2022, 10:27:50 AM

Title: Topping E70 Velvet DAC
Post by: HAL on December 17, 2022, 10:27:50 AM
Decided to order the Topping E70 Velvet DAC with the AKM AK4499EX DAC.  This is a 32bit R2R balanced output DAC.  The new version is a two IC implementation since their foundry fab fire took out that one IC line.  Going to use this with the headphone rig.

I heard a prototype of the original one IC AK4499 in the dspNexus 2x8 and sounded better than the stock AK4493EQ DAC.  Problem was the prototype ran at 104C, so component longevity would not be good, so a redesign in the future might happen.  Since the production unit is not released, still TBD.

Will see what happens.

https://apos.audio/products/topping-e70-velvet-desktop-dac-digital-to-analog-convertor?_pos=2&_sid=79e63c641&_ss=r
Title: Re: Topping E70 Velvet DAC
Post by: ejk on December 17, 2022, 10:34:38 AM
I was checking that out the other day. Let us know how it sounds. If you could hook it up as a Pre for a bit, I would be more interested.
Title: Re: Topping E70 Velvet DAC
Post by: Nick B on December 17, 2022, 10:59:00 AM
Decided to order the Topping E70 Velvet DAC with the AKM AK4499EX DAC.  This is a 32bit R2R balanced output DAC.  The new version is a two IC implementation since their foundry fab fire took out that one IC line.  Going to use this with the headphone rig.

I heard a prototype of the original one IC AK4499 in the dspNexus 2x8 and sounded better than the stock AK4493EQ DAC.  Problem was the prototype ran at 104C, so component longevity would not be good, so a redesign in the future might happen.  Since the production unit is not released, still TBD.

Will see what happens.

https://apos.audio/products/topping-e70-velvet-desktop-dac-digital-to-analog-convertor?_pos=2&_sid=79e63c641&_ss=r

Will be interesting to get your thoughts as you’re an analog guy. Am curious, what dacs you might have tried before this one.

Nick
Title: Re: Topping E70 Velvet DAC
Post by: jmc207 on December 17, 2022, 03:33:33 PM
I was checking that out the other day. Let us know how it sounds. If you could hook it up as a Pre for a bit, I would be more interested.


I too would am interested in your impressions, especially if hooked to a preamp.

Thanks, John
Title: Re: Topping E70 Velvet DAC
Post by: HAL on December 17, 2022, 05:23:37 PM
I will post my feedback, but it will go into my headphone rig without a preamp or as the preamp depending on how you look at it since it will control volume. 

My speaker system uses a DSP as the preamp, even for phono.
Title: Re: Topping E70 Velvet DAC
Post by: Nick B on December 18, 2022, 09:18:49 AM
Decided to order the Topping E70 Velvet DAC with the AKM AK4499EX DAC.  This is a 32bit R2R balanced output DAC.  The new version is a two IC implementation since their foundry fab fire took out that one IC line.  Going to use this with the headphone rig.

I heard a prototype of the original one IC AK4499 in the dspNexus 2x8 and sounded better than the stock AK4493EQ DAC.  Problem was the prototype ran at 104C, so component longevity would not be good, so a redesign in the future might happen.  Since the production unit is not released, still TBD.

Will see what happens.

https://apos.audio/products/topping-e70-velvet-desktop-dac-digital-to-analog-convertor?_pos=2&_sid=79e63c641&_ss=r

Will be interesting to get your thoughts as you’re an analog guy. Am curious, what dacs you might have tried before this one.

Nick

Sorry Rich. I got my “Hal’s” mixed up. Still interested in your impressions
Title: Re: Topping E70 Velvet DAC
Post by: HAL on December 23, 2022, 06:43:38 AM
Well it arrived late, so now it is sitting in the post office until I get back next week.  :(

The setup will be the E70 feeding my iFi headphone amp and Audeze LCD MX-4 phones.   Might be able to get my old battery powered Erno Borbely headphone amp working.  My attempt at a stereo volume control I worked on with Gary Dodd with LDR's, works, but it is tweaky.  Probably just put my Alps Black Beauty 100K Ohm stereo control back in.  It is a bit of a Frankenstein build. :)



Title: Re: Topping E70 Velvet DAC
Post by: HAL on December 23, 2022, 09:11:43 AM
here's two possibilities for ldr pots that won't break the bank:

http://diyparadise.com/shop/index.php?main_page=index&cPath=18 (http://diyparadise.com/shop/index.php?main_page=index&cPath=18)
i used this for a few years between my melos ma333r and outboard x-over when the melos was acting up - it was at least as transparent as the melos' ldr pot, even tho it was an additional component and interconnect in the chain. (there's a less expensive eva shown on the website, that's only a single input but a bit less expensive; afaik they won't make it anymore; otherwise i'd have bought that one. eva2 has 3 inputs.)

and this - someday when i get motivated, i'm gonna put one of these in the melos, to replace the $15 pos alps pot that assfuck mark porzilli put in when he was too lazy to properly fix the volume control after he'd sat on it for 3 years:
https://tortugaaudio.com/products/diy-preamp-components/electronic-stepped-attenuator-epot-v3-mini/ (https://tortugaaudio.com/products/diy-preamp-components/electronic-stepped-attenuator-epot-v3-mini/)

doug s.

Well it arrived late, so now it is sitting in the post office until I get back next week.  :(

The setup will be the E70 feeding my iFi headphone amp and Audeze LCD MX-4 phones.   Might be able to get my old battery powered Erno Borbely headphone amp working.  My attempt at a stereo volume control I worked on with Gary Dodd with LDR's, works, but it is tweaky.  Probably just put my Alps Black Beauty 100K Ohm stereo control back in.  It is a bit of a Frankenstein build. :)

doug s.
Mine works and has adjustable impedance for the LDR's.  The adjustment range is just a bit limited.  Not sure I hear enough difference compared to the ALPS Black Beauty 100K Stereo pot to make the difference worth while. 

A stepped volume attenuator with Texas Components/Vishay bulk metal foil would be my preference with a really good silver contact rotary switch.   
Title: Re: Topping E70 Velvet DAC
Post by: HAL on December 27, 2022, 03:36:20 PM
The Topping E70 Velvet DAC arrived today.  Now to get it setup in the headphone rig for a try.
Title: Re: Topping E70 Velvet DAC
Post by: HAL on December 28, 2022, 05:15:10 AM
The Khozmo stepped attenuator with the remote is similar to the design I used.  Just an Arduino uC board controller to really nice audio relays like Gary used in his preamps and buffers.   All on a protoboard to test the design.

For the first trial using Dale/Vishay metal film resistors to test before purchasing the Texas Components naked metal foil resistors.  Really good channel matching at 0.01% tolerance for the values.  Will see what happens.
Title: Re: Topping E70 Velvet DAC
Post by: ejk on December 28, 2022, 05:55:56 AM
Hi Hal. I umderstand what you want to use it for but some of us are curious how it sounds as a 2 channel preamp. If you could do.me the favor when you have a chance to hook it up to your stereo system I would greatly appreciate it
Title: Re: Topping E70 Velvet DAC
Post by: HAL on December 28, 2022, 12:37:37 PM
ejk,
The stereo system is down due to water problems in my listening room.  It will be a long process before it is up and running.  This is what I have until then.

The E70 Velvet DAC is setup in the headphone rig.  Now to let it run-in for 24 hours for more listening.


Title: Re: Topping E70 Velvet DAC
Post by: HAL on December 28, 2022, 02:15:21 PM
I did max out the iCan volume control and used the E70 V digital control.  Sounds much better to me than the iCan volume control at the same approximate setting. 

The E70 V has 0.5dB/step settings, so would need a voltage output check to make them exactly the same.

The remote works well and sets the filter in the DAC for 6 different types.  The F-4 setting is minimum phase slow rolloff that I prefer.

Will check more tomorrow after some time.
Title: Re: Topping E70 Velvet DAC
Post by: ejk on December 28, 2022, 03:07:35 PM
ejk,
The stereo system is down due to water problems in my listening room.  It will be a long process before it is up and running.  This is what I have until then.

The E70 Velvet DAC is setup in the headphone rig.  Now to let it run-in for 24 hours for more listening.




NP sorry to hear. Maybe Rollo can help with the water issue
Title: Re: Topping E70 Velvet DAC
Post by: HAL on January 03, 2023, 03:08:24 AM
The E70 V DAC has been running for days with the iFi iCan headphone amp.

Sounds great to me with no noise background and all instruments sound natural.  That is with my preferred minimum phase filter in the AK4499 DAC F-4 selected. 

Will be testing it with other headphone amps as from past trials the Borbely Audio HPA is a better sounding setup.  Since the E70 V has a digital 0.5dB/step attenuator, I can just direct drive the HPA and use the DAC as the volume control.  Just need a good input resistor to ground for the HPA.

This should be interesting.
Title: Re: Topping E70 Velvet DAC
Post by: HAL on January 10, 2023, 06:09:20 AM
Topping had some E90 Discrete headphone amps that were refurbs available, so got one to go with the E70 Velvet DAC. 

Running them fully balanced and they sound really good in the headphone setup!  To me, much better than with the iFi iCan heaphone amp.

The AKM AK4499 DAC has finally surpassed my other favorite DAC the Wolfson Micro WM8741 in sound quality. 

It took a few hours for the E90D to fully warm up, but it is working well.  Finally get to run the planar headphones fully balanced.  :thumb: