Webb 6-14E amp service/tune-up, Sarno mod and more

John McClung · Post by **John McClung** » 18 Jan 2009 10:02 pm

Ken, I have two Webb 614-E's, the older one, #752, is very "hissy" as the volume I play at goes up. The other amp, #920, is hissy, just less so.

The hiss diminishes as I roll off the Sensitivity knob. The older amp I bought new in about 1978, and it used to be very quiet. I normally play with Sensitivity at near max, and Volume at about 3, very low. It still has great tone, but the noise is getting intolerable.

Does your mod eliminate this obnoxious noise? My NV400 is much quieter, by comparison.

Ken Fox · Post by **Ken Fox** » 19 Jan 2009 5:35 am

I would suspect those old caps are getting very noisy. I just did an older Musicman and a Peavey tube amp this weeks with similar issues! New caps did the job on them for sure.

I replace every electrolytic cap in the Webbs as well as the tone caps. It makes for a very nice sounding amp.

I also carry all the transistors in the Webbs, pilots lights, most of the pots as well.

John McClung · Post by **John McClung** » 19 Jan 2009 5:42 pm

Ken, are you saying the refresh you do SHOULD eliminate the hiss in a Webb, or WILL eliminate the hiss? Do you plug in a Webb guts through an external speaker before and after to assess the actual sound improvements? Thanks!

Ken Fox · Post by **Ken Fox** » 19 Jan 2009 5:51 pm

It might well take care of it. If not it well due to be done on these older amps. Those caps are quite old!!

Any other noise would likely be transistor noise. Without it on the bench there is no way to tell 100 percent.

I use a shop test speaker and I also load test with a sine wave for signal, a large resistor bank for a load and a scope to check the output signal.
have several reverb tanks and cable assemblies to test the amps as well (as there were variations over the years)

For sure, it would not leave my shop with any strange noises!!

John McClung · Post by **John McClung** » 19 Jan 2009 10:12 pm

Sounds great, Ken, I'll be in touch. You modded my ProFex II a few years back and that was a great improvement.

David Pinkston · Post by **David Pinkston** » 24 Jan 2009 2:23 pm

Ken-

Is there a way to know if a Webb would benefit from an upgrade? Are there any tell-tale signs that would let you know you should service it. It's not using much oil so it may be okay...

Ken Fox · Post by **Ken Fox** » 24 Jan 2009 5:09 pm

One of the great benefits is replacing all of the electrolytic caps in the amp. If it is an early amp it will benefit from that for sure.

I also change the audio coupling caps from the cheaper electrolytic caps to nice film caps in both the preamp and the power amp. The caps in the tone control section are also changed to film caps. So far all I get is real positive feedback about the tone of the modded amp!

I really think it is not so much a mod as new and better parts. We are not redesigning any circuits in the amp.

I check for dirty pots and clean them if needed. I also clean the rotary switch for the 3 tone settings. Jacks are cleaned as well. The amp is load tested on a load bank rated for 400 watts to verify the amp is putting out full power.

Ken Fox · Post by **Ken Fox** » 26 Jan 2009 5:50 am

Just ordered more kits. Will have then in a few days.

Average 1 day turn around at this time.

John McClung · Post by **John McClung** » 26 Jan 2009 6:24 pm

Ken, in both my old Webbs, the hiss almost disappears when the EQ 5-band section is turned on. Why is that? I would think adding more controls would add more noise and problems.

I don't need any EQ from that section, but may use it until I get them serviced by you.

Ken Fox · Post by **Ken Fox** » 26 Jan 2009 6:37 pm

The preamp always feeds the EQ input. The EQ switch connects the power amp input to the preamp out or the EQ out (which is always connected to the EQ board input).

So if it is quieter it could be a bad switch or perhaps the EQ is filtering out some of the noise.

Hard to saw total without putting it on the bench for check-up

Ken Fox · Post by **Ken Fox** » 11 Feb 2009 9:46 am

Roger Crawford · Post by **Roger Crawford** » 11 Feb 2009 1:44 pm

Ken modded my '78 model, and actually got to hear it in use at the Northwest Georgia Steel Guiar Show in Atlanta on 2/8/09. You wouldn't believe the number of compliments I had on how the Webb/Mullen G2 combo sounded. Thanks, Ken!

Ken Fox · Post by **Ken Fox** » 2 Mar 2009 4:32 pm

We have have kits on hand and have about a one to two day turn around.

Will be closed for the Dallas show.

We are not installing kits or working at the show. Look forward to seeing everyone at the show!!!

Ken Fox · Post by **Ken Fox** » 7 Apr 2009 11:47 am

Ken Fox · Post by **Ken Fox** » 11 May 2009 4:29 pm

Have kits and ready to go to work!

Ken Fox · Post by **Ken Fox** » 20 May 2009 12:53 pm

Ken Fox · Post by **Ken Fox** » 23 Jun 2009 6:33 pm

We will get all repairs and mods out that are in not later than Monday, July 13.

We will also have two weeks closure around labor day, to be announced later.

Thanks again for all the work from the Steel Guitar Forum. We are proud to be of service!!!

Ken and Ruth Fox

Ken Fox · Post by **Ken Fox** » 17 Aug 2009 4:16 pm

The Steel Guitar Forum

Webb 6-14E amp service/tune-up, Sarno mod and more

Webb upgrade question