iRIAA Filter is now a "1/2-kit"

hagtech · « **on:** 11 Sep 2003, 06:09 pm »

Hello all. I have created a 1/2-kit out of the iRIAA Filter. New manual is online. DIY to save $ or to customize into an enclosure.

The 1/2-kit concept has proven to be extremely popular with DIYers. I plan to continually add to the lineup. Next out will be an all tube preamp, similar in construction to the Cornet.

I appreciate all the ideas and suggestions. Thanks for building!

jh

The Oracle · « **Reply #1 on:** 16 Oct 2003, 08:38 am »

May I suggest one stage only, with minimal gain - maybe 3 to 10dB - or the ability to change the gain depending on the power amp gain.
A remote transmitter/ receiver to control a motorised potentiometer would be great! (Dact's are rather expensive)
Is there a ballpark price for a 1/2 kit - and predicted DIY completion price?

The Oracle

hagtech · « **Reply #2 on:** 17 Oct 2003, 04:43 am »

I just don't follow your suggestions. You want a motorized volume control for a FryKleaner?

jh

Brad · « **Reply #3 on:** 17 Oct 2003, 02:54 pm »

He's asking about the preamp you mention at the end of your first post.

The Oracle · « **Reply #4 on:** 17 Oct 2003, 07:53 pm »

Brad passes the accidental 'lateral thinking test' - sorry
To follow on - It would be very easy and convenient to build in the same chassis as Cornet using same transformer and rectifier (for those that intend to build both at once)
Remote volume for something like Alps or Panasonic pots

The Oracle

hagtech · « **Reply #5 on:** 18 Oct 2003, 03:09 am »

My bad. Yes, the preamp will be flexible in terms of part upgrades & such. Basic board & chassis will be a great value, but also easy enough to tweak in your favor.

One great example of an upgrade is the new remote control volume kit from Bent Audio. He made a controller that powers a DACT attenuator and uses a real IR remote. Nicely done. I will make room for it in the suggested chassis. John's doing a new version to run from 6.3Vdc instead of 12V. For us.

The circuit is a SRPP (inverting) stage of moderate gain. Maybe 10dB or a bit more. Balance control and mono switch. Four inputs, two outputs. No tape loop or anything. Simplicity.

Yes, it will use same power supply circuit as Cornet. Working on improved chassis design. My thought is to create the "Constructor" series of kit components. The "Clarinet" linestage is what we're talking about. Then maybe a headphone amp or DAC. All tubed. Lots of common components. Family resemblance.

Completed cost in the ballpark of $300.

jh

Brad · « **Reply #6 on:** 18 Oct 2003, 03:56 am »

Hey Jim,

Nice to see you and John Chapman working together on things. All the better for us the consumers. What tubes will you be using in the Clarinet?

Any chance of sneaking an RIAA circuit in?

Tube preamp with remote and tube phone stage - getting pretty close to perfection.....

Cheers from Houston

EDS_ · « **Reply #7 on:** 18 Oct 2003, 04:13 am »

JH-------

You have my full attention.
I'll be looking for your 1/2kit pre-amp.

I've had a hankering for an all analog system for my office.
Any long-range plans for a power amp 1/2kit?

Great idea.

hagtech · « **Reply #8 on:** 19 Oct 2003, 05:21 am »

Yeah, power amp thoughts bouncing around my head for some time. Been considering it for years. Here's where I'm headed: push/pull 300B or 2A3 or similar triode with no feedback. Maybe autoformer output instead of tranny, fully differential throughout, transformer coupled driver stage. Gee, sounds a lot like what Lynn Olson has been doing. Also a touch of Moth. Still mulling over possible innovations and uniquness. I don't want to be a copycat. Whatever I come up with, it will have some novelty. Not sure if it will be 1/2-kit or not. Might need to simplify it a bit for 1/2-kitness.

Don't wait around. It will be a long time before I ever get there. Buy what you need now!

Oh, and John (BENT) is a great guy to work with. There will be more of that, too. Working with Kevin Carter (K&K), Horace Atkinson (IAG), Thom & Peter (REDPOINT, GALIBIER), etc.

jh