DIY Dodd Buffer

TrungT · « **Reply #660 on:** 24 Dec 2010, 04:47 am »

Don
To me Platinum by-pass caps give a deeper, tighter bass, more detail and open, wider detail, you can just get the basic kit and add the by-pass caps later and you will hear the change in sound (take awhile to break in the by-pass caps)
Don't forget to get the 6H30 tube for it.

nodiak · « **Reply #661 on:** 24 Dec 2010, 05:56 am »

Thanks for the reply TrungT. I was thinking to go about it that way. I'll do some searching about the 6h30. Think its shipped with 6n1p. I'm curious to try other tubes in that circuit.
Don

TrungT · « **Reply #662 on:** 24 Dec 2010, 06:08 am »

Don
After rolling few tube around, to me 6H30 is the best.

You can start with Sovtek tube under $35.
Your Dodd buffer kit come with upgrade heatsink, so you are all set.

If you need any help please drop me a note.
Happy holiday.

Atlplasma · « **Reply #663 on:** 24 Dec 2010, 02:46 pm »

Has anyone compared the different flavors of 6H30 tube? The Sovtek and EH brands seem to be the more affordable ones. Has anyone tried the DR Supertube?

TrungT · « **Reply #664 on:** 24 Dec 2010, 03:36 pm »

^^^^^
I using Sovtek and EH, the both almost sound the same, EH may be little quieter.
I have not try DR tube yet.

Atlplasma · « **Reply #665 on:** 4 Jan 2011, 05:51 pm »

I received my Dobb Buffer yesterday and spent a couple of hours soldering. I'm beginning to think a jeweler's visor might be in order.

Atlplasma · « **Reply #666 on:** 4 Jan 2011, 10:45 pm »

Quote from: TrungT on 23 Nov 2010, 09:40 pm

Can you explain how you grounded your inputs and outputs? Did you solder the ring tabs on each one to a common piece of copper rod and then ground the copper rod to the chassis?

TrungT · « **Reply #667 on:** 4 Jan 2011, 10:59 pm »

All ground a connected together.
You can use the RCA ground as a main ground bus.

stonedeaf · « **Reply #668 on:** 5 Jan 2011, 10:55 pm »

In trying to figure out if a Dodd buffer is in my future - I've run into one puzzling spec ?
My greatly appreciated Sony XDR-F1HD HD tuner lists the following :
Audio Output
Output Level .7V rms at 47 Kohms
Recommended load impedance over 10 Kohms
I think the Sony manual is probably wrong - but haven't found a test so far that lists the tested audio output impedance for this product. I doubt the 47Kohm figure is accurate and can't imagine why they would tell you to run a higher impedance into a lower impedance ?

TrungT · « **Reply #669 on:** 5 Jan 2011, 11:24 pm »

^^^^^
I has a Sony HD tuner, Dodd buffer and Virtue One.2 classic sound great.

HAL · « **Reply #670 on:** 5 Jan 2011, 11:58 pm »

I believe the spec means that you get 0.7Vrms when it has a 47K ohm load attached.

The next line recommends a load impedance higher than 10K ohms for the Sony HD tuner.

jtwrace · « **Reply #671 on:** 7 Jan 2011, 12:53 am »

Here are some pics of the single tube conversion with the 6H30.

Thanks again Gary!

TrungT · « **Reply #672 on:** 7 Jan 2011, 01:06 am »

^^^^^
Looking good, now how's it sound?

jtwrace · « **Reply #673 on:** 7 Jan 2011, 01:35 am »

Quote from: TrungT on 7 Jan 2011, 01:06 am

^^^^^
Looking good, now how's it sound?

Waaaay to early. It works and sounds like my buffer so that's a start.

TrungT · « **Reply #674 on:** 7 Jan 2011, 01:51 am »

JT
What's tube you have on?

jtwrace · « **Reply #675 on:** 7 Jan 2011, 01:52 am »

Quote from: TrungT on 7 Jan 2011, 01:51 am

JT
What's tube you have on?

6H30

TrungT · « **Reply #676 on:** 7 Jan 2011, 01:58 am »

^^^^^
Pi or Dr?

jtwrace · « **Reply #677 on:** 7 Jan 2011, 02:00 am »

Quote from: TrungT on 7 Jan 2011, 01:58 am

^^^^^
Pi or Dr?

http://thetubestore.com/ehx6h30.html

TrungT · « **Reply #678 on:** 7 Jan 2011, 02:12 am »

Good choice

jtsnead · « **Reply #679 on:** 7 Jan 2011, 05:02 am »

OK got my buffer up and running, thanks for the advice from Trung, jtwrace and any others I might have spoke with.

Quick note anyone else that buys a built one when you plug in the 12volt
power cable in the back make sure you turn it to lock it in, I did not know
this and did not get any power on. So after tracing the power from the battery to the end of the cable, then testing the fuse still nothing until I realized you
had to turn the connector to lock it DOH!

Also quick question I know some people leave the charger attached to the battery when you are using it, I bolted the power cable to the battery terminals
and then attached the charger clamps to the battery terminals is this how everyone else does it?

First listening tonight this thing sounds awesome, all the things I like about
tube pre's, great vocals, great imaging along with the dynamics and clarity of solid state pre's, using the 6h30pi tube for now.