Mods for Grant Fidelity TubeDAC-11 coming soon

Wayne1 · « **on:** 18 Feb 2012, 04:28 pm »

In an earlier post, I mentioned that tabrink had lent me his Grant Fidelity DAC-11 for evaluation. I compared it to an analog modded Touch, run off a modded linear power supply, and found it came up short. I far preferred the sound of the modded Touch to that of the TubeDAC-11.

After using the TubeDAC-11 for a bit, I finally decided to see if there was anything I could do to improve the sound a bit. With tabrink's permission I tore into the TubeDAC-11 and started analyzing the circuit and parts used. The tube output came first. It is using a simple cathode follower as a buffer. Certain parts were removed. Other parts were changed to higher quality. The power supply was next to be looked at. Again, I found some parts that could be changed for higher quality ones. The output of the I/E section was next to get worked on.

I have been letting it run in for a couple of days now, and I must say the changes have really opened up the sound of this inexpensive DAC. I will be sending it back to tabrink on Monday. I would prefer to have him give his impressions of the changes to the DAC. After he comments on it, I will offer the mod on the website. The cost will be around $250.00 for the mod and I do believe all will find it money well spent.

As with all mods, the work I do will void the warranty from Grant Fidelity.

gooberdude · « **Reply #1 on:** 19 Feb 2012, 04:37 am »

Sign me up. After the mods $600 total spent for a pretty good front end with built in tube dac.

Can you add remote control?

The dac-11 imaging is decent right out of the box. Do your mods flesh out the midrange or enhance bass any?

Levi · « **Reply #2 on:** 19 Feb 2012, 04:43 am »

I only expect nothing but awesome from your work! Please keep us up-to-date.

Wayne1 · « **Reply #3 on:** 21 Feb 2012, 06:22 pm »

The TubeDAC-11 is on it's way back to tabrink. Hopefully he will comment soon after he receives it.

I am VERY impressed with the sound of this DAC after the mod. It is definitely a bang for the buck unit with the mod.

The bass does improve quite a bit. Imaging is where I pick up some major changes. I'll let Tom comment more when he gets the DAC in his system.

I have noted some other areas in the DAC that could use some help. The cost of the parts does rise rapidly. For instance, the bridge rectifiers used in the three power supply circuits collectively cost under $0.75. They also sound like they cost. To improve them with HexFreds in that case style would run close to $100.00. It will make an improvement, but is it worth the cost?

gooberdude · « **Reply #4 on:** 21 Feb 2012, 11:44 pm »

Wayne,

Probably a newbie question, but when you're poking around a component for the 1st time & inspecting the circuits, is the volume inside the case a big concern? There's not much room inside the dac-11.

I'll be a guinea pig on a modd'd dac-11 soon. Looking forward to tabrink's experiences.

matt

Wayne1 · « **Reply #5 on:** 22 Feb 2012, 12:01 am »

The volume inside the case, the lead spacing of components, how much height the board is raised off the bottom of the case, how close the components are to the AC inlet, etc. All these things come into play when deciding what components to use in a mod. Of course the circuit design is the most important. Once that has been figured out then comes the choice of what exact part to use that will work in the circuit and then fit in the space.

I can be somewhat creative in how I get things to fit. I have some experience from modding the Touch and SB3 before that in working with very small spaces and replacing surface mounted parts.

While I would love to be able to used Jensen coupling caps in certain mods, the limited space often precludes that. I do my best to use the highest quality, and to my ear the best sounding, parts that will fit.

shadowlight · « **Reply #6 on:** 22 Feb 2012, 12:46 am »

Wayne,

Would you recommend getting a modded TubeDac or get the full Touch modification with bybee rails Jerome. I currently have the latest moded Jerome minus the bybee and stock touch.

Wayne1 · « **Reply #7 on:** 22 Feb 2012, 03:13 am »

Quote from: shadowlight on 22 Feb 2012, 12:46 am

Wayne,

Would you recommend getting a modded TubeDac or get the full Touch modification with bybee rails Jerome.

How about both

The Bybee Rail will help out the sound of any power supply used with either a stock Touch or any of the mod levels. What I heard from the modded TubeDAC-11 before it left here was better sound than the analog modded Touch. I was feeding it with a digital modded Touch powered from a Music Railed PS. I did not listen to it with a stock Touch or stock power supply.

IMHO, I do believe all the mods do add up. You do have to decide what works best for you.

So far the hierarchy is get a linear power supply, then mod the Touch. Go for the Music Rail in the power supply. Use a modded DAC with a modded Touch and Music Railed modded power supply.

tabrink · « **Reply #8 on:** 3 Mar 2012, 04:21 am »

Way late getting this out! And afraid to log in and look at PM list.
Well I received my Tube DAC back from Wayne albeit my buns have been on the road but I unboxed, stuck in my favorite tube, hooked it up tonight and instantly remembered why I really like this DAC. The DAC-11 Fed via my Wayne modded Touch and ByBee railed psu sounds clear and not hesitant It is a musical piece and now I mean I hear more notes while listening to David Grisman and Jerry Garcia. I hear the plucking on the mandolin strings and Jerry's grunting.
I always thought this was a great value DAC and now I think it is punching in another weight class. In the weeks to come I hope to run it some more, compare to my AVA Vision Hybrid DAC.
I do have to say Wayne has a way of tweaking stuff to get all of the horsepower out of it.
He has breathed some clarity and timing into this DAC that has tightened up the bass and smoothed the top end.
I never found this DAC too bright but now I do feel it is more accurate and timely while not being all tingly top and bloated bottom.
Overall I feel Wayne has made this a keeper and it will be focal point of my near field system.

Wayne1 · « **Reply #9 on:** 3 Mar 2012, 03:33 pm »

Thanks for the comments, Tom.

I will be offering the mod through the website for $250.00.

I'll try to get it posted this weekend.

I stated earlier in the thread that more can be done to the DAC, If you own one and are willing to spend a bit more on mods, please contact me so we can discuss this.

RodH · « **Reply #10 on:** 6 Mar 2012, 01:48 am »

Hi!
New member here. A solid member recommended I should come join your esteemed ranks.
I am Canadian, well acquainted with Mr. Ian Grant, and an ownwer of a new DAC-11. I have had many Grant pieces over thae last few years with good results.

Disclaimer: I am NOT affiliated with Grant Fidelity in any way.

Mods? Oooh! I am very interested.
I have owned 4 DAC-09's - all passed off to new happy owners now, but improving my DAC-11 has certianly got my attention!

Please elaborate if you can.

Rod in Canada.

SteveFord · « **Reply #11 on:** 6 Mar 2012, 10:42 pm »

Are one of these being passed off to me?

Wayne1 · « **Reply #12 on:** 6 Mar 2012, 11:05 pm »

Hello RodH,

Welcome to AC.

What is it you wish to know?

The mods currently are concerned with the tube buffer stage. Some parts are removed and some are replaced. There are changes made to some of the power supply caps and associated parts.

There are other things that can be changed in the power supply section that would brings about more changes, but the cost would go up quite a bit.

Please feel free to contact me by e-mail if you wish.

Wayne1 · « **Reply #13 on:** 12 Mar 2012, 06:05 pm »

Mod for Grant Fidelity Tube DAC-11 is now on the website for ordering.

Parts are in stock for the mods. I think all will be impressed with what this DAC can sound like after the mods.

Alexdad54 · « **Reply #14 on:** 12 Mar 2012, 06:14 pm »

I'm thinking of getting a TubeDAC-11 and have you mod it but I was wondering if it would be possible to replace the spdif out with a BCN connector on this DAC as part of the mods (with the price adjusted accordingly of course)?
thanks,
Dave

Wayne1 · « **Reply #15 on:** 12 Mar 2012, 06:26 pm »

A BNC can be used. There would have to be a bit more work done to use one than most units. All the inputs and output are directly connected to the circuit board.

It is possible, just a bit harder than other units. Send it on in

brother love · « **Reply #16 on:** 12 Mar 2012, 06:38 pm »

Quote from: Wayne1 on 12 Mar 2012, 06:05 pm

Mod for Grant Fidelity Tube DAC-11 is now on the website for ordering.

Parts are in stock for the mods. I think all will be impressed with what this DAC can sound like after the mods.

Hey, that is a photo of my "unmodified" TubeDAC-11 ! Do I get a Mod discount for use of this ?

abongiov · « **Reply #17 on:** 14 Mar 2012, 07:56 pm »

So if I got this right $350 for the TubeDAC11 + $250 for the Mod = $600 with the stock PSU.
Where do it stand in the already crowded DAC market ? IS it in the same league as an EE minimax + that sells at $1100 ?
And is it the same logic as the touch ? Get a PSU first and then Mod ?
Then what's the final price and where does it stand then ?

Sorry is this seems stupid but completely new to the all Mod thing. If I don't own a TubeDAC-11 already is there better value out there for the price of the TubeDAC + Mod + PSU ?

Wayne1 · « **Reply #18 on:** 14 Mar 2012, 09:47 pm »

The Grant Fidelity TubeDAC-11 does not need any external power supply. The mods I offer do help it sound better than stock. I have not compared it to an EE MiniMax DAC Plus.

I guess it depends on the rest of your system and how you plan to use it. The TubeDAC-11 can be used as a pre-amp and headphone amp. The EE DAC Plus cannot. The DAC chip, power supply and tube circuit are a bit "better" in the EE DAC Plus.

abongiov · « **Reply #19 on:** 15 Mar 2012, 09:01 pm »

Wayne,

Thank you for your answer. Good to know that it does not need additional PSU. I am looking at the DAC market right now and alot of those have 15-30 days trials. Let's say I want to buy a TubeDAC and have it Mod before comparing it to another one, then I just killed my trial (and warranty) period. Comparing the TubeDAC before Mod will be useless unless it is already better than a 600/700 Dac.
I know it has alot of functions but still it would be buying without auditioning. So I see the value for TubeDac owner but unsure of the value for someone looking to buy now.

Tabrink did you compare it to the AVA ? If so, I am sure alot of us would be happy to know your impressions.

Thanks