NV112 Chip Removal, Replacement & Initial AB Testing

[Dick Sexton]

I just received and installed the OPA2134PA chips in my 112. Here is how I did it as I took photos. See comments. For informational purposes only. http://cid-594320d13092d8fb.skydrive.li ... %20Install

[Terry Sneed]

Hey Dick, how do you like your tone with the chips installed, verses without the chips? I put the chips in a Nashville 112 I had, and also I had a Nashville 1000 with the chips in, and I like the tone better with the new chips in. They seem to take the shrill out of the highs, and seem to make the reverb sound better also. IMO.
BTW- Thanks for the instalation pictures, wish I'd had em when I put the chips in my 112. It would have made the process a lot easier.

terry

[Jack Stoner]

As I'm a tech, I have an IC removal tool that I use to remove chips and I also have a grounding wrist strap that I use and ground to the chassis to avoid any potential static electricity problems.

That is the "safe" way to remove and replace IC chips.

[Dick Sexton]

Terry, I immediately heard a difference in the sound of my steel through the modded amp. I have two NV112s sitting side by side, one modded one not. The one I put the OPA2134PAs into had the Burr Brown Fox chip mod that I'd previously installed in it. With the exact(close as possible) same control settings on both amps, the modded amp sounded crisp(for a better word), had good to better string separation then before. It also "Seemed to Sustain Better" up the neck and slightly changed the "Feel" of my pot type volume pedal. That said, I was not use to the sound and opted to move the controls to get a sound I was use to. Still, I like the change in my amp. I have not played the amp out as yet, possibly this weekend. I plan to take both and A/B them.

Jack, your absolutely right. I should have put up a picture of my forearm with the grounding strap attached. I did use one. My bust, or my wife's, she took the picks of the chip actually being removed. Sorry. As for my choice of "Chip Removal Tool", I first tried the tool I had, a tweaser type chip remover. The chips were tight flushed against the top of the socket, with near to no room to insert the tool. I've seen chips damaged many times being removed with this type tool in a similar situation. I was pretty sure everyone would be able to find a sharp object(Like an Exacto Knife) and there was plenty of room to get my trusty old pocket knife in position to do the extraction. I found the chip came out easily once it was raised slightly on one end. Actually, I was surprised how easily the chips did come out, the older Mil Spec chip sockets I'm accustom to, don't normally release the chips that easy.

Again, sorry for the safety oversight. Good idea to use a Grounding Strap. And always preferable to use the "Proper Tool For The Job". Both available from an Electronics Supply or your local Radio Shmack! Better yet, take it to a tech.

[Terry Sneed]

Dick, I have my wires crossed as usual. I was refering to the Burr Brown chips that I installed in my Nashville 112. I had forgotten about the post on the 'amps for sale' forum where Ken was introducing the new chips. I may have to try those on my Nashville 1000 sometime.
terry

[Dick Sexton]

Initial AB tests results of the OPA2134PA Chip modded NV112 amp and an unmodded NV112 amp.

Test platform:

Derby Steel with George L E66 pickup. Ernie Ball Volume Pedal using a regular type cord from steel to pedal, George L cord from pedal to amp, plugged into the "High Gain" input. The amp setting are, Pre Gain 2.5, Low +12, Mid 0, High 0, Presence -2, Reverb 3.5, Post Gain 3... The delay is plugged into the Pre EQ Patch using George L cords and I am using the exact amount of delay I use normally( about one echo). This is and are the settings I used on both amps. Other then turning an amp on or off and moving the delay from one to the other(without changing it), no other changes were made.

Test:

I pulled up Keith Whitleys, Until a Tear Becomes a Rose and played along with the Youtube. The song changes keys in the middle, that is where I changed amps. I did this several times, alternating first the amp with the Mod and then amp with the original chips. If I used the modded amp on the first part of the song and the un-modded on the last, I continued using the un-modded amp onto the first part of the song the next time, switching to the modded amp on the last part. By doing this I was not playing only one amp on only one part of the song. This test was conducted at a moderate level, in my music/practice room.

Findings:

The modded amp is noticeably cleaner sounding, has better string separation, as well as better clarity, all the way up the neck. I personally even think it has better sustain, but this I can't explain. I am extremely pleased with these initial tests and am excited to move on to playing a gig with the modded amp. I find this mod, the OPA2134PA Chips to be a positive change to my sound.

Of course other opinions may vary and other results may be gotten from other test platforms.

Dick Sexton

[Bill A. Moore]

After Jack, and others extolled the virtues of these chips, I had to put a set in a Bandit 112 I have for repair. I have yet to complete the new cabinet for it, so I don't know what the final sound will be. I can say that the idle noise is almost nonexistant. The usual hiss or "breathing" I normally associate with inexpensive Peavey amps is gone!
It's amazing what you can learn on this forum, and I grateful that the knowledgeable will share. When I read about the Burr Brown , or Ken Fox mods, I had visions of Ken slaving over a hot soldering iron, swaping out R/C values on the circuit board, (like the older amps). I guess I still have a lot to learn!
Thanks to all for the information!

[Bobby Burns]

As far as the mods go, the chip mod, is not the same as the intense mod that Ken does to an amp. On the intense mod, or the session mod, I assure you, Ken does his share of slaving with the soldering iron.

[Ken Fox]

On a Session 400 or LTD there are two boards, the preamp and power amp. About 34 parts are replaced. On a N-400 36 parts are replaced!

Here is the preamp board of an LTD 400 after the mod

[Bill A. Moore]

So the intense mod is intense?

[Ken Fox]

You betcha! All power supply caps, audio coupling caps and tone caps replaced. Jacks and pots tested and cleaned. Amp load tested on a 400 watt test load and audio tested with a speaker and my favorite Tele as well.

Lots more going on there than just a few plug in chips for sure

[Dick Sexton]

DESCRIPTIONS from data sheets, paraphrased.

The OPA2134 (Burr Brown) is a dual, operational amplifier, of ultra-low distortion,
low noise fully specified for audio applications.
A true FET input stage was incorporated to
provide superior sound quality and speed for exceptional
audio performance. This in combination with
high output drive capability and excellent dc performance
allows use in a wide variety of demanding
applications. In addition, the OPA2134’s wide output
swing, to within 1V of the rails, allows increased
headroom making it ideal for use in any audio circuit.

The OPA2604 (Burr Brown) is a dual, FET-input operational amplifier
designed for enhanced AC performance. Very low
distortion, low noise and wide bandwidth provide
superior performance in high quality audio and other
applications requiring excellent dynamic performance.
New circuit techniques and special laser trimming of
dynamic circuit performance yield very low harmonic
distortion. The result is an op amp with exceptional
sound quality.

[Ken Fox]

Just put a set of OPA2134 in a N112 and a Jensen Neo speaker, 4ohms 100 watt.

Mighty fine sound and a weight reduction. It went from 43 pounds to a nice light 36.5 pounds.

[Dick Sexton]

Last night I played my first steel gig using the OPA2134PA chip modded NV112. I had all intentions of ABing both the modded and unmodded 112s, swapping at the mid show break. I did not end up doing that. The modded amp was a winner from the start and I did not want to degrade my sound in the second half. I even had two very good steelers in the audience comment how good the rig sounded. One got up and played a few on my Derby, later mentioning he intended to swap out the chips in his NV1000. Needles to say, I am pleased.

Tonight, I am going to play a guitar gig using the modded amp. My buddy will be playing his Derby, using his unmodded NV112. I will let him play a few songs through the modded amp. Then take it back...

[Greg Wisecup]

If I like it, you may have trouble trying to get it back!

[Dick Sexton]

Sorry buddy maybe next time...

[David Collins]

Played my first gig with my Nashville 112 with the 2134 chips this morning. WOW! Less hum and noise from the amp with volume pedal off. Cleaner, sweeter overall sound.

Mids that you can actually use, and like.

Playing an Emmons PP into Hilton pedal into High Gain input on Nashville 112. No other effects. Reverb even sounds better to me. I go direct to the main board from the preamp out, and use the amp speaker at low volume just to monitor steel. Sound tech noticed an overall more manageable signal to mix. Mid eq had always been an issue, NO MORE.

Best bucks I've spent in years!

[Ken Fox]

Best thing I have tried in years for these Peavey amps! Everyone is pleased so far, it seems.

[George Macdonald]

I put in a set of the OPA2134PA in my Nash.112 yesterday to replace the OPA2604 chips. While I thought the amp sounded good, I didn't realize just how good until a friend brought over his 112 with the first "mod" in it. What a dramatic difference in the two amps. I play a 12 string universal and the bottom end and mid-range is so much clearer with the new chips. The other amp sounded muddy to both of us compared to mine with the OPA2134PA chips. The amp with the new chips is definately louder too, although that doesn't particularly matter. Just my 2 cents. Thanks to Ken Fox for the heads up.

[Gianni Gori]

Just put a set of OPA2134 in a N112 and a Jensen Neo speaker, 4ohms 100 watt.

I have just installed on my NV112 the OPA2134 chips that I received from Ken. They work great!
All the comments I had read here about those chips are true: they provide a real improvement in notes separation and in sustain. Everything is clearer and with less hum. I am very satisfied with that mod!!!

About the Jensen NEO speaker, is it worth giving it a try? Since Jensen speakers are made in Italy, I could get one at a relative cheap price...

[Earl Foote]

Just ordered me a set for my 112

[Dick Sexton]

Yesterday, while the family visiting over the weekend, headed off to the Casino with some of my money, I installed a set of OPA2134PA chips in my backup NV112.

It may just be me, and other opinions may vary of course, but I am blown away with this mod. I now have the sound, I've been dreaming of someday having. It is literally, the best sounding amp I've ever had. I think, if you have an NV112 and 20 bucks, you owe it to yourself and the people you are playing for, to at least try this mod.

Clarity like never before, string separation like never before, and I'll swear, I think my sustain has increased.

That was the third amp I have modded, Two NV112s and one NV1000. I have two more NV1000s coming in next week to get their chips installed.

Oh, this last one I did, I didn't even have to change the amp settings from the setting I was using with the original chips. Unbelievable!

[Larry Bressington]

Ken, is there an up-grade op amp for the Nashville 400?
Is the 112 big enough for stage gigs?
Sorry i've read too many threads already.

[Ken Fox]

Yes, the N-400 kit is on my website

[Clete Ritta]

I just replaced the five 2604's in my NV1000 with 2134's.
It took all of about 20 minutes.
I can hear a difference in tone as well.
It sounds noticeably cleaner, louder and warmer to me.
I'm a happy camper!

Clete