MDAC First Listen (part 00101101)

[TimR]

Hi John, Am I correct that the phono stage feeds only into the ADC and there is no option to bypass the ADC? After all your hard work to design a reference-quality phono stage, do you think it would be worth having (or is it feasible to have) an analogue phono-stage output so that the FDAC L3 MM/MC could also be used as a stand-alone high quality analogue phono-stage?

I'm thinking this would then allow an analogue pre-amp to be connected between the FDAC phono-out and the FDAC av-bypass input to provide the option of switching the turntable between ADC and end-to-end analogue.

 

[highfi]

Based on Fusion5's useful example, I calculated the total cost of purchase for the FDAC Phono Stage (assuming one purchases L3 only so as to enable the Phono-Stage option), including step-up transformers. Could anyone please confirm or correct? Thanks!

Development:
100 GBP (L3)
100 GBP (Phono Stage)

Production:
GBP 350 (L3 PCB) This is in addition to the charge for L2 PCB, not instead of. Please confirm.
GBP 100 Phono stage electronics (worst case scenario, GBP50 to GBP100)
GBP 500 MC step-up transformers (stereo pair, most expensive option)

GBP 218.5 (EU VAT 23%)
GBP 35.15 (Duty - DACs normally get classified as signal boosters, HS code 8543.70.9099 for EU, 3.7%)
Shipping: There is no additional shipping charge for the above options.
Total: GBP 1403.65 (1833.91 Euros)

 

[ti33er]

I was under the impression that L3 was only a little bit more than L2...simply an ADC - not a total of £450 more than without ADC!? I.E. Not £100 Dev + £350 ADC component!

 

[fusion5]

I think you've made several mistakes in your calculation. Presuming you only wanted to calculate the addional cost to an FDAC L2:

Development:
100 GBP (L3)
100 GBP (Phono Stage)

Production:
GBP 50 (L3 PCB upgrade, average extra charge) You don't need both PCBs.
GBP 100 Phono stage electronics (worst case scenario, GBP50 to GBP100)
GBP 150 CNC Chassis upgrade (worst case scenario, GBP100 to GBP150) The CNC screening is mandatory for L3 MM/MC units. I presume you didn't fit this with your L2.
Shipping: No additional costs, right. I positioned this item next to the production costs because VAT & duty apply to this for imports.

GBP 69.00 (EU VAT 23%) There is no general EU VAT rate. UK 20%, Germany 19%, I suppose 23% where you're located.
GBP 11.10 (Duty - DACs normally get classified as signal boosters, HS code 8543.70.9099 for EU, 3.7%)

Total: GBP 580.10 + Lundahl step-up transformers

GBP 500 MC step-up transformers (stereo pair, most expensive option) I didn't include this item with the others because Lundahl is an european company. I see absolutely no reason why to export the step-up transformers to china and then re-import them.

 

[fusion5]

I was under the impression that L3 was only a little bit more than L2...simply an ADC - not a total of £450 more than without ADC!? I.E. Not £100 Dev + £350 ADC component!

Yes, without the MM/MC option you just need to pay the £100 L3 Dev and the price differerence (+VAT, +Duty) between the L2 and L3 PCB.

 

[LittleToast]

Hi John,

I have made 3 payments so far. I have not track this project for over a year I think. Recently, I try to go into the wiki as well as the mdac2 site to take a look but I am not totally certain. I am a bit lost. I think to continue the journey, I should be paying another 100GBP for L2 development. I need a guide as to how much I need to pay in order to get the MDAC that I hope to get - I think by now there are quite a few variants. What are they? I do not need the chasis as I have a working MDAC with me now. Do help guide me along. Thank you.

 

[JohnW]

John, is there any possibility of having the Phono Stage mode of operation/settings on the remote control, too?

Yes, the Phono stage Gain and various other setting can be selected via Remote Control.

Also, just checking: will the FDAC be suitable for playing vinyl REAL-TIME, in addition to recording vinyl to computer/USB thumb drive? Thanks!

Yes, there as realtime 14 MHz sampling mode for Direct ADC / Phono Playback.

 

[highfi]

Yes, the Phono stage Gain and various other setting can be selected via Remote Control.

Yes, there as realtime 14 MHz sampling mode for Direct ADC / Phono Playback.

Exceedingly cool!

 

[JohnW]

Once again, I'm lost. JohnW, what have I paid and what am I due to pay?

Hi John,

Well I'll give you credit for the ADC development fee (for the loan of your Phono stage), I need to confirm with Renata later how much you have paid so far - currently I'm in the Lab working with Jarek on the FDAC design.

 

[JohnW]

I was under the impression that L3 was only a little bit more than L2...simply an ADC - not a total of £450 more than without ADC!? I.E. Not £100 Dev + £350 ADC component!

The Basic L3 is GBP100 for development and say an extra GBP100 "At Cost" Max for the ADC / components.

The L3 MM/MC option which adds the Phono stage adds more cost...

 

[JohnW]

Hi John,

I have made 3 payments so far. I have not track this project for over a year I think. Recently, I try to go into the wiki as well as the mdac2 site to take a look but I am not totally certain. I am a bit lost. I think to continue the journey, I should be paying another 100GBP for L2 development. I need a guide as to how much I need to pay in order to get the MDAC that I hope to get - I think by now there are quite a few variants. What are they? I do not need the chasis as I have a working MDAC with me now. Do help guide me along. Thank you.

LittleToast,

Noted, I'll confirm with you later, I'm currently in the Lab with Jarek working on the FDAC design.

 

[JohnW]

Hi John, Am I correct that the phono stage feeds only into the ADC and there is no option to bypass the ADC? After all your hard work to design a reference-quality phono stage, do you think it would be worth having (or is it feasible to have) an analogue phono-stage output so that the FDAC L3 MM/MC could also be used as a stand-alone high quality analogue phono-stage?

I'm thinking this would then allow an analogue pre-amp to be connected between the FDAC phono-out and the FDAC av-bypass input to provide the option of switching the turntable between ADC and end-to-end analogue.

The FDAC Phono stage is designed as an integral part of the ADC circuit - so its not possible to extract the analogue signal without extra circuit complexity....

 

[highfi]

Channel D specialise in turntable / RIAA transcription software (Pure Vinyl) for Apple OSX machines they also have a range of MC / MM Pre-amplifiers.
The FDAC's internal Phono stage emulates the feature set of there Seta Model L / Model H Pre-amplifier (Gain settings / RIAA and Non RIAA modes) etc.
http://www.channld.com/

I hope the FDAC competes on sonic grounds, too (I have no personal experience of the Seta).

 

[highfi]

From a Hardware perspective the units will be DSP ready for Room EQ / active Crossover - but we are at the mercy of MiniDSP once the units are in production.

With Jarek expertise once he joined our little Lakewest design team has made it possible to include an ARM CPU with an SDcard slot etc. The ARM CPU SD controller can only support upto 32GB. It is only meant as a storage device for local recording sessions / test file playback etc. not as a full blown music server (although 32GB holds upto 50CD's)....

1. Are we also going to be at the mercy of MiniDSP's pricing decisions?

2. Perhaps a more future-proof solution for larger and/or upgradeable capacity could be considered? Or does the FDAC enable a music server in other ways?

 

[timola]

1. Are we also going to be at the mercy of MiniDSP's pricing decisions?

2. Perhaps a more future-proof solution for larger and/or upgradeable capacity could be considered? Or does the FDAC enable a music server in other ways?

MinDSP software (and hardware) is very reasonably priced in my opinion....$10 US a plug-in I think.

The ARM cpu module is restricted to a maximim of 32GB...The FDAC as far as I know is not going to be a music server....its a very advanced DAC at heart.

 

[markomarko]

Any news/timelines on the fdac-lite development? fdac l2/3 is a little rich for me

 

[highfi]

Channel D specialise in turntable / RIAA transcription software (Pure Vinyl) for Apple OSX machines they also have a range of MC / MM Pre-amplifiers.

The FDAC's internal Phono stage emulates the feature set of there Seta Model L / Model H Pre-amplifier (Gain settings / RIAA and Non RIAA modes) etc.

http://www.channld.com/

The Seta features:

• Internal Low Noise AGM Rechargeable Battery Power Supply

• Cartridge Loading: External Switch

• Precision Cartridge Channel Balance TRIM Control

It's not clear whether the FDAC will emulate these features. Of course, it does not emulate Seta's pricing, either.

 

[sprint]

Quote:
Originally Posted by TimR View Post
Hi John, Am I correct that the phono stage feeds only into the ADC and there is no option to bypass the ADC? After all your hard work to design a reference-quality phono stage, do you think it would be worth having (or is it feasible to have) an analogue phono-stage output so that the FDAC L3 MM/MC could also be used as a stand-alone high quality analogue phono-stage?

I'm thinking this would then allow an analogue pre-amp to be connected between the FDAC phono-out and the FDAC av-bypass input to provide the option of switching the turntable between ADC and end-to-end analogue.

I am struggling to fully understand how the phono stage option actually works with the FDAC and would appreciate a fairly simple explanation of how it would be used, as I was assuming that it could/would be used as a stand alone phono stage/amp if required/desired?

Clearly you feed the output from your T/T cartridge cable, MM/MC, into the phono stage of the FDAC but then what happens to signal within the FDAC and how is it outputted to your amp. My amp only has line level RCA inputs, MF integrated Nu-Vista.

 

[fusion5]

The FDAC phone stage sits in front of the Analogue-to-Digital Converter (ADC). The converted signal enters the FDAC digital domain and can be listened to like any other digital source. You can apply all available processing like room correction to the signal. Besides that there is an ADC record option.

There is no direct analogue signal path for the phono stage.

 

[JohnW]

Any news/timelines on the fdac-lite development? fdac l2/3 is a little rich for me

We worked on the projects until 6am this morning - poor Jarek, I'm tuning him into a vampire designer!

The FDACLite current purpose is to help optimise and FDAC Sound quality and test the USB Software etc, as such there will be a few engineering units floating around in March /April but no priority plans to put it into production - its sidelined as we concentrate on the Detox / FDAC.

FDACLite will be released as a product in its own right, but FDAC takes priority - so it depends how it can be slotted into production. During my trip to China in March I'll discuss the production scheduled our manufacturing partner.