Another newbie who has been bitten by the audio bug...

ronthereptile · Post by **ronthereptile** » Sun Dec 09, 2007 4:24 pm

Hey Guys,
I have been getting into the audio stuff for a few months (4) now. It is nice to find a site to ask a few opinions. My current set up is as follows...

Radio- Main
Kenwood TS-850 (virgin- no mods)
Kenwood DSP 100
Back up Arriving Friday-
Kenwood TS-870 (70's serial #, still a virgin as well)
Current Back up
Icom 756 Pro- Leaving in exchange for TS-870
Little helper
Kenwood TL922A

Audio-
Mic - Marshall MXL 770
Behringer mic 2200 pre amp
Behringer tube composer T1952
Behringer DEQ 2496
Behringer Virtualizer Pro 2024
Radial Engineering ProDI box

Spare parts- DBX 286A pre amp
Behringer PEQ 2200 5 Band Parametric EQ
Behringer Xenyx 802 mixer board

I have been experimenting with the setup so far,and been enjoying the results. I go through the rear of the 850 and intend to do the same on the 870. I will do the IC131 mod on the 870 the first day I get it. I would love some advice on the menu settings for the 870, as well as what you think about my rack order placement. Any other mods you think the radios may need to take full advantage of the wonderful Kenwood audio would be appreciated. I'm sure I will be asking a lot more questions in the future, so I'll thank you in advance for all the ball busting that I will be putting you guys through!

Thanks,
Ron in the Great White North... VA3ASO

Post by **Voodoo Guru** » Thu Dec 13, 2007 9:01 am

Howdy Ron!
So glad you could join us on the Forum!!

Sounds like you are on the right road for Voodoo Machines.
The 870 is a great Rig right out of the box.
The 850 makes a fine ESSB unit after its mods.

The only other mod we could suggest is the mods to Flatten the Receiver and the Transmitter.
This is shown on Page #44 of the 870 Service Manual.
Makes a big difference.

Your Unit placement is:

Mic - Marshall MXL 770
Behringer mic 2200 pre amp
Behringer tube composer T1952
Behringer DEQ 2496
Behringer Virtualizer Pro 2024
Radial Engineering ProDI box

We would suggest this:

Mic - Marshall MXL 770
DBX 286A pre amp
Behringer DEQ 2496 (using only the PEQ)
Behringer tube composer T1952
Behringer Virtualizer Pro 2024
Radial Engineering ProDI box

Reasoning behind using the DBX for the preamp is twofold.
1 - It is a cleaner Pre.
2 - It has a Downward Expander for noise gating. It is placed in the correct position behind the Mic Pre.

Another option you have is to use the DEQ inside the 2496.
This is actually a multiband compressor and will perform better then the T1952.
You could use channel one of the DEQ2496 for the PEQ and then channel 2 for the DEQ.
This will require you to get very familiar with the Menu's and how to program the unit to make it function correctly.
NU9N's site gives lots of info on this.

If you ever get a EX3200, the placement would be between the PEQ and the T1952 Compressor.
If you opt to use the 2 channel method with the DEQ2496 using the PEQ and DEQ, then place the EX3200 between the channels of the DEQ2496.

OK Hope that helps,
Take Care!

ronthereptile · Post by **ronthereptile** » Mon Dec 17, 2007 5:37 pm

Hey Thanks!...
I always knew the 286A was better, but it doesn't match as well! LOL...
I will try the changes you suggested and listen for the difference. I will say that my 850 with the dsp100 blows the 870 away as far as width. 6k sounds real nice (to those of us who can hear it!) . I knew that would be the case, but I do like the feel of the 870 a bit more.
Is there any other settings on the menu I may be interested in? DO I need another peice of rack gear? hehehe

....
I will let you know how it pans out....
Thanks again...

Post by **Voodoo Guru** » Mon Dec 17, 2007 5:45 pm

We'll be waitin!!
Merry Christmas!!

ronthereptile · Post by **ronthereptile** » Mon Dec 17, 2007 9:08 pm

OK,
I went throught the back of the radio and it sounds really good. I want to do the C131 mod in a couple days to help out the bottom end. It is pretty heavy right now, so I would imagine the mod will make it sound even better. I do have a question about the RX/TX flattening on page 44 in the service manual. Will I notice a real difference? I like to do mods that make a difference I can hear.

Post by **Voodoo Guru** » Tue Dec 18, 2007 6:18 am

Great on the ACC2 input on the 870.
That will remove the '870 Splat' from the highs.
It is also a little Flatter in TX Response, especially when the C131 mod is completed.
You will have to Re-EQ to compensate.

If you use Spectra Plus or some other kind of Audio Spectrum Analyzer on your computer, You can see the 3db drop they are talking about.
Just listen to the receiver white noise without the antenna connected and you will see that the Receiver Frequency Response is not completely 'FLAT' as people say it is.
Kenwood designed a Frequency Compensation in both the Receiver and Transmitter circuits, just as they said they did in the Service manual on page 44.
After the Service Manual Mod, it is RULER FLAT.

As far as hearing a deference, well it depends on how sensitive your ears are.
We could hear a major difference, as could W5UDX, but you may not.

We have some pictures of the components that need to be changed if you are interested.

Let us know.
Take Care,

ronthereptile · Post by **ronthereptile** » Tue Dec 18, 2007 7:55 am

We have some pictures of the components that need to be changed if you are interested.

That would be very helpful. I'm sure I can find that resistor package size at my local electronics parts store. Now, if only they sold the updated DSP Proms !!!!

ronthereptile · Post by **ronthereptile** » Tue Dec 18, 2007 2:00 pm

Hey Guys,
I did the C131 and the flat RX mod (didn't have the right resistor for the TX mod). Holy crap!

What a difference! The bottom end came up big time. I had to re-eq to get it under control. If anyone questioned doing the C131 for rear input (as I did), let me tell you it was worth it. It doesn't take long at all, and you will be very pleased with the results. Now to just do some tweaking with the rack gear placement, and see if it can sound even better. I can't imagine it sounding much better than now, but you never know....

Thanks Again,
Ron

Post by **Voodoo Guru** » Tue Dec 18, 2007 8:24 pm

Kuhl Icon!
Yea, its pretty awesome aighnt it!!
The amount of difference it makes is terrific.
Guess you wont be needen the pictures now, huh!!!

Your one step closer to Audio Nirvana!!!!!
Take Care,