Quilter Steelaire Amp Question

[Malcolm McMaster]

Keith, I like them BUT I don't sell them, and incidently I use them with YOUR volume pedal and have done for about five years with NO problem.

[Chris Parks]

This is going to be a touchy subject so I will leave it at this. (and I won't say what I really want to as it would likely be an epic debate.)
I have fielded hundreds of calls about noise and ground loop hum. I can honestly say over 70% of my support calls are to help someone find the bad solder-less cable in their rig.
That pretty much sums it up as politely as I can.
(P.S. Other manufacturers have shared similar frustrations with me.)

[Tom Campbell]

Nobody seems to mention the "dirty" current supplied by the power companies, bad wall outlets and outdated wiring in our homes and playing venues. Not to mention various sound effect/enhancers we connect to our amps.
I played a church service where my Peavey NV400 wouldn't power up...the outlet tested out way under 110. Brought the amp home and it worked perfectly.

[Chris Parks]

This is an enormous problem as well and one of the reasons we build in a well regulated universal power supply into all Quilter amps.
(I have made them work at 72 Volts AC on a variac.)
But even here at the lab we get an occasional weird zzzzzzztttt! So noise can happen although the amp is usually well poised to take care of spurious noise sources in a given environment. That said we can't even test a product in the front room as we have a "key fob" entrance coil at the front of the building that transmits right into any nearby pickups. Makes a horrible noise.
So environment is a key issue as well. Look around for sources of spurious noise. Sometimes it would surprise you.
My personal two funny stories are: A fellow who complained about a weird tremolo sound emitting from his Quilter amp. (He realized after much troubleshooting that it went away when he turned his ceiling fan off.) and a girl who could not get her amp to stop buzzing. (Her neighbor had 10K watts of HID lights in the marijuana farm adjacent to her apartment.)
The point about effects pedals is also well taken. Let me tell you it is a jungle out there. I have seen pedals with poor grounding, bad line voltage returns, DC on the signal, Micro-phonic pedals... you name it I have seen it.
The funny thing is that we do wind up becoming experts in lots of other gear as we are the source where folks hear it so they assume somehow the issue is with the amp since it usually is the newest piece of the rig.

[Keith Hilton]

Malcolm, thanks for using my volume pedal. I am happy you have experienced 5 years of no problems. Chris, like you, I have seen a lot of things building guitar pedals for the last 20 years. Had a guy call and tell me when he put his foot on my pedal it would start humming. I drove to where the guy was playing in a night club. Sure enough, when I put my foot on the pedal it would start humming. The harder I pushed down "vertical" on the pedal, the louder the hum. I put some dry towels under the pedal, and there was no hum, even pushing down hard. Come to find out the night before a waitress had spilled a pitcher of beer on the carpet.
When the carpet became wet equipment on the band stage was trying to ground to it, since there was no ground on the wall plug.
Probably the most strange noise thing I have ever encountered happened in the shop while testing pedals. I got this hum, and worked almost a day trying to figure it out. Come to find out the cause of the hum was the leg of my steel guitar touching a base board electric heater. Even though the base board heater was painted, the leg of my steel touching it somehow conducted. The thing that made it really crazy was the fact that the base board heater had "no" electricity connected to it. To this day I have not figured that one out. For any hum, there is a reason. If you look long enough you will normally find the reason.

[Malcolm McMaster]

Chris, Keith , thank you for taking the time to answer this thread, both first class excellent products and service from both you guys.I appreciate you guys have much more experience in electronics, but can only go by my own experience with equipment, I don't doubt for a moment what you are saying, but as I said having used solderless plugs and cables for ten years without problems,believe good maintenance helped the only failure was when I tripped over guitar to pedal cable and ripped plug off) , I will continue with them.If I do have a problem first thing I will do is swap them over to standard cables ,as advised by you guys, to see if that cures it,Thanks again for your help and advice, much appreciated.

[Chris Parks]

Malcolm no worries... If it works for you then I am all for it. I am just relaying my own experiences. As is always said, your mileage may vary.
I do recommend re-doing them once a year or so to take care of corrosion which will build up. Just trim them an eighth of an inch or so on each side, and maybe spray some De-Oxit inside of the plug.

As a thought, a good prophylactic measure for anyone in a high humidity environment is to do that with all of your cables and jacks. Use a moistened cloth and wipe down jacks and maybe a small plastic bristle brush in a barrel configuration to scrub out the inside of the jacks and clean the contacts.

[Tony Glassman]

At the risk of topic drift, what soldered cord (or components) sound tonally similar to George Ls ?

[Marco Schouten]

At the risk of topic drift, what soldered cord (or components) sound tonally similar to George Ls ?

I like the Evidenceaudio Lyric HG. Bright as the GL, a bit more definition in the mid tones. Not cheap though.

[Marco Schouten]

I did a small test at home today:
At the Quilter I have channels 1 and 2 combined, both at 8. I put the master volume at 6.
I put the volume pedal at maximum volume, I use a cable of 1 meter between guitar and volume pedal and a 6 meter cable between the volume pedal and the amp.
First I used my Evidenceaudio cables, measured the noise level, than I used my GeorgeL cables, measured the noise. Repeated the tests one more time.
With the Evidenceaudio cables the noise level was between 2.5 and 3 dB lower than with the GeorgeL cables. I can imagine that the differences can be bigger in different situations.

[Steven Paris]

I believe the reason for differing results regarding the noise from Steelaire amplifiers is a recent change.
From Pat Quilter:
"We did make an improvement almost a year ago. We upgraded the opamps to OPA 1654 which are the quietest available FET-input devices. The previous generation used TL-074 opamps which have a standard noise figure. The improvement is about 8dB."


This would make the newest amps MUCH quieter than the older ones----8 db less noise is a LOT!!!
Solderless cables have caused me NOTHING but headaches. They are UNRELIABLE. Give me good quality connectors (Neutrik, Switchcraft) SOLDERED to low capacitance quality cable(Canare LV-61S) ANY DAY over George-L or any other solderless nightmares.

[Bob Lawrence]

re: From Pat Quilter: low capacitance quality cable(Canare LV-61S)

Interesting cable choice.

[Bob Lawrence]

re: OPA1652

Description

The OPA1652 (dual) and OPA1654 (quad) FET-input operational amplifiers achieve a low 4.5-nV/√Hz noise density with an ultralow distortion of 0.00005% at 1 kHz. The OPA1652 and OPA1654 op amps offer rail-to-rail output swing to within 800 mV with a 2-kΩ load, which increases headroom and maximizes dynamic range. These devices also have a high output drive capability of ±30 mA.

These devices operate over a very wide supply range of ±2.25 V to ±18 V, or +4.5 V to +36 V, on only 2 mA of supply current per channel. The OPA1652 and OPA1654 op amps are unity-gain stable and provide excellent dynamic behavior over a wide range of load conditions.

These devices also feature completely independent circuitry for lowest crosstalk and freedom from interactions between channels, even when overdriven or overloaded.

The OPA1652 and OPA1654 temperature ranges are specified from –40°C to +85°C.

Features

Low Noise:
4.5 nV/√Hz at 1 kHz
3.8 nV/√Hz at 10 kHz
Low Distortion: 0.00005% at 1 kHz
Low Quiescent Current:
2 mA Per Channel
Low Input Bias Curren

http://www.ti.com/product/OPA1654

===================================================
TL074 - Quad Low-Noise JFET-Input General-Purpose Operational Amplifier

Features 3 Description
The TL07xx JFET-input operational amplifier family is 1• Low Power Consumption
designed to offer a wider selection than any
• Wide Common-Mode and Differential Voltage previously developed operational amplifier family.
Ranges Each of these JFET-input operational amplifiers
• Low Input Bias and Offset Currents incorporates well-matched, high-voltage JFET and
bipolar transistors in a monolithic integrated circuit. • Output Short-Circuit Protection
• Low Total Harmonic Distortion: 0.003% Typical The devices feature high slew rates, low-input bias
and offset currents, and low offset-voltage • Low Noise
temperature coefficient. The low harmonic distortion Vn = 18 nV/√Hz Typ at f = 1 kHz and low noise make the TL07xseries ideally suited for
• High-Input Impedance: JFET Input Stage high-fidelity and audio pre-amplifier applications.
• Internal Frequency Compensation Offset adjustment and external compensation options
are available within the TL07x family. • Latch-Up-Free Operation
• High Slew Rate: 13 V/μs Typical Device Information(1)
• Common-Mode Input Voltage Range PART NUMBER PACKAGE BODY SIZE (NOM)
Includes VCC+


http://www.ti.com/lit/ds/symlink/tl072b.pdf

[Steven Paris]

I think you misinterpreted my post: the choice of cable is MINE, NOT Pat Quilter's. The Canare LV-61 is extremely flexible (as is the GS-6), but has significantly lower capacitance (LV-61:201 pf/10Ft; GS-6: 480 pF/10Ft) and significantly less $$$ ($4.10/10Ft vs $7.90/10ft). That means I can make an EXCELLENT quality, RELIABLE, TRANSPARENT-sounding 10 foot cable for about $7. NO NEED for a $25/$80/$100 "boutique" cable!!@!

[Gary Reed]

To: Alan Simon,

From Pat Quilter:
"We did make an improvement almost a year ago. We upgraded the opamps to OPA 1654 which are the quietest available FET-input devices. The previous generation used TL-074 opamps which have a standard noise figure. The improvement is about 8dB."

Alan,
Are you using this newer amp?

[Steven Paris]

Evidently Quilter will upgrade the older amps to the newer specs with OPA 1654 opamps for $100 plus shipping both ways.I think this is a significant improvement;the 1654 FET opamp is one of the best available.

[Paul Stauskas]

For me, the source of noise was from a rack effects unit. Chris P. helped identify the issue and recommended using stomp box units instead. I haven't had any problems with excess noise since.

[Bob Lawrence]

@Steven Paris

my post: the choice of cable is MINE, NOT Pat Quilter's. [/quote]

It's only because at the time you have everything lumped together in one paragraph, as a quote from Pat Quilter. Now that you have edited the post and separated the 2 statements I can see the difference.