TUBE EQ VS SOLID STATE EQ SDR OPERATIONS

[FREDDY BISHOP SWL]

I plan on renewing my ham ticket soon.  I inherited a Tube voice processor  TL AUDIO 5051. I have a ANAN 200d sdr. Would the audio sound warmer/vintage with the [tube pre amplifier ] 2 Best EQ to use ( A) Builtin 10 band eq or ( B) 4 band tube eq My goals are to just improve the audio if possible

[Opcom]

Just an opinion:

I don't think a listener at a receiver will be able to tell the difference between the warm tube sound of a single item in ther audio chain versus the solid state counterpart. The other voice processing effects normally in use, plus the noise of the transmission path, would cover up many little nuances even further.

Locally, that is the local RF sample, maybe you can tell the difference when doing an A/B recording and then listening to playback if the other processing is kept to bare minimum and the experiment is done scientifically.

In my opinion regarding ham radio which uses only voice, it's only a matter of circuit choice, or what looks good in the rack, or perhaps something similar to a religious matter.

I use tubes in the station where possible because it pleases me to have classic circuits.
I have no expectation that anyone can tell the difference at the other end as long as everything is working properly.

In broadcast music where fidelity, power, and wide audio bandwidth is highly important for musical reasons, perhaps tube vs solid state could be carefully discerned at a 'good' receiver.

Does the Anan have a way to load a software 'tube amp' as part of its audio DSP? (sacrilege for the religious types).

Tampering with tessitura! 

Do what pleases you and gives the EQ curve you want.

[W7TFO]

As usual, Pat is spot on.

73DG

[Steve - K4HX]

Moving this to the Tech section where it belongs.

[Steve - K4HX]

Suggest you read this before doing anything.

http://amfone.net/Amforum/index.php?topic=4780.0

[Opcom]

I'd forgotten about that great article. Thanks for bringing it up!

[WBear2GCR]

Tubes?

The tubes do next to nothing. Most of it is transistors and opamps.
The opamps will dominate the sound. (yes, they are not transparent)

Unless I needed this thing for recording, I'd sell it in an instant and buy some
ham radio gear, or something else that would actually help in some way.

You can use it for your Anan. But you'd best really really understand exactly how
it works and what the knobs do. Only my opinions here.

                             _-_-bear

[Opcom]

That circuit reminds me of buying a modern can of chili and knowing that it does in fact contain meat, but the product is more like a sauce and I can't readily identify the meat.
OK that is cruel, someone spent time designing it and there's nothing wrong with it for what it does. The totem pole transistor stages acting as impedance converters in the plate circuits are novel.

But I remember many years ago, when chili had a lot of meat in it, and each brand a distinctive flavor according to the meats.

Starting on page 232 of this 'handbook' are four articles from 1941 to 1956 containing parametric tube circuits that in two cases include the tube in a feedback loop so that it is deeply involved in whatever is being accomplished for good or ill.
http://bunkerofdoom.com/kb/goth/AGH-AM-027p.pdf
(save-as, it's 264MB)

Building a tube EQ or parametric EQ might better follow the lines of the latter. The old way.

(though, still no one at the other end of the circuit will know of these wonders unless so informed, and it's a lot of work to build such magnificent things)

Attached, is schematic of a simple non-parametric, multiband, feedback-based tube EQ which is not included in the 'handbook' document.