EV-1 Phono/Cartridge Match

[28gauge]

I have had an EV-1 phono pre-amp for years with a Basis turntable, Rega RB300 tonearm and a Benz Ace .8mv output cartridge. The Ace is old and needs replacement. It always seemed to lack some output in my system. My question is this. The CJ phono has 49db of gain. I'm considering the Dynavector 10x5 Mk ll, which has 2.8mv of output. Is that too much output for the EV-1, and what might the issues be?

[AnotherJohnson]

I don’t think it’s too much. It would be considered a medium output level, and 49 dB phono gain should be ok. Note that EV1 overload is at 200 mV.

The DV 10x5 mk 2 shouldn’t be real sensitive to loading, and the CJ phono preamps get along well with most cartridges.

FWIW, I don’t think that cartridge would need any more preamp gain. I think it could be a good match.

SEE THE 20th AND 21st POSTS IN THIS THREAD FOR A COPY OF THE EV-1 OWNERS MANUAL courtesy of SteveFord.

[Joe Appierto]

In addition to being a good match as AJ states, there are also some internal DIP switches inside the casework that could be used to provide further tailoring of the unit's response curve.

[admin]

My previous turntable was a rega planar 3 with the same RB300 arm and dynavector 10x5 cartridge (not the MK2 though). A great performance vs cost combo in my opinion which I was very happy with and gave me years of listening pleasure. You should have no problems with that combo and the EV1.

[AnotherJohnson]

In addition to being a good match as AJ states, there are also some internal DIP switches inside the casework that could be used to provide further tailoring of the unit's response curve.

I was disappointed that CJ does not have the owners manual available for download on their vintage products site.

If the EV1 is adjustable, a good starting point would be 47kOhm and lowest capacitance. Any loading above 1kOhm will meet DV’s specs, and the actual capacitance is typically not a big issue for HOMC cartridges.

Different resistance loading may present discernible differences, but my experiences is that the TEA1 and TEA2, along with the Audio Research phono sections I’ve owned, are not nearly as finicky about the loading as any of the solid state phono sections I’ve owned.

One problem with this hobby is that participants often “learn” a lot of stuff on forums and in magazines that may be true for the writer’s system, but is completely off base for the reader’s. So people gush over getting the loading exactly right, when in fact, unless you’re test signal matching with an FFT and two channel scope, there’s no way to know.

So … if there are switches, and they don’t have skull and crossbones, red, or yellow warnings on them , have at it and set them to suit your own taste.

[Joe Appierto]

The EF1 was the solid state counterpart to the EV1. This may not apply to the EV1 but these are the control settings for the DIP switches in the EF1. Maybe they apply to the EV1.

Load Selectors: To select an input load impedance other than the
factory preset 47 kohms unplug the EF1, and remove the cover. The
input impedance of the EF1 is set by the load selector switches - the two
dual inline pin (dip) switch arrays located near the input connectors at
the back of the unit. Each dip array includes four switches labeled 1
through 4. Load impedances are selected as follows:
impedance switch #
1 2 3 4
47 kohms o o o o
9.6 kohms x o o o
1.9 kohms o x o o
500 ohms o o x o
200 ohms o o o x
x indicates switch in "on" position
o indicates switch in "off" position (indicated by arrow on switch)
Be sure to set both switches. Replace cover. Do not operate the unit
with the cover off.

[admin]

I was disappointed that CJ does not have the owners manual available for download on their vintage products site.

Odd, as they have manuals available for download for most of their vintage unites, including all the way back to the PV-1. Maybe they sold their last one and never made a copy?

[AnotherJohnson]

I could be wrong, but the EF1 looks like a more versatile unit, even having three gain settings. The EF1 overloads at a lower input level too.

[Joe Appierto]

Yes, it's more flexible. I haven't read any reviews of the EF1 so don't know how the two stack-up in terms of overall sound. The use of FETs (guess that's why the "F" in the model's name) versus tubes/valves in the EV1 and the switchable gain settings seem to be the major differences. Even with the similarities it's a shame they didn't post the manual for the EV1.

[roberto]

EV1 VACUUM TUBE PHONO-EQUALIZATION PRE-AMPLIFIER

— Introduced in September, 2000
The EV1 was a separate phono equalization preamplifier designed to provide the additional gain and RIAA equalization that modern phono cartridges require.
Based on the circuit used in conrad-johnson’s acclaimed Premier Fifteen, the EV1 used a single-ended triode input amplifier comprised of both sections of a miniature twin–triode tube connected in parallel for reduced noise. A second single-ended triode amplifier provided added gain. A passive network of precision components between these two stages set the required frequency equalization. A direct coupled cathode follower output stage yielded a low output impedance.
The EV1’s circuit employs no negative feedback loop. The EV1 was a simple, low-noise, high-gain device well suited for use with a wide range of phono cartridges of both moving magnet and moving coil types.

V1 & V2: 12AX7 | V3: 5751 | V4: 12AU7

Specifications:
Gain: 49 dB
Phono Overload: 200 mV
Distortion: less than .05% THD or IMD
Phono Equalization: within +/- .25 dB of RIAA
Hum and Noise: 78 dB below 10mV input
Phase: phase correct

Mechanical:
Dimensions: 14.375D x 19W x 3.315H inches
Weight: 14.5 lbs.

[AnotherJohnson]

Maybe there’s no owners manual download because the blurb you’ve shared from the vintage products page is all that there is to know.

[Joe Appierto]

That blurb doesn't say how to set the two (presumably left and right channels) internal DIP switches which the EF1's manual describes.

[AnotherJohnson]

That blurb doesn't say how to set the two (presumably left and right channels) internal DIP switches which the EF1's manual describes.

Does it really have them?

I doubt that it does.

I think the tube phono preamp is less finicky about loading the cartridge than the solid state phono preamp. That’s been my experience. Sit in front of any Audio Research phono preamp and bask in the luxury of on the fly from your seat load changes via the remote control. Reviewers used to remark on how subtle the changes were as you moved from one end to the other. Take a Linn Uphorik and change some cartridges from 53 to 47, and note the significant difference.

CJ doesn’t even have any capacitance options until you get to the TEA1 level.

So … I don’t know if the EV1 has the dip switches, but as a tube phono preamp, if they’re there, don’t be surprised if an HOMC cartridge doesn’t really effectively exploit them.

[Joe Appierto]

According to the Soundstage March, 2002 review http://www.soundstagenetwork.com/vinyl/vinyl200203.htm :

"The input load impedance is factory preset to 47k ohms, which is where I left it, but there are internal load selector switches that can be set for four other impedance values."

That having been said, switching them around may not make a hill of beans difference but they are there just as they are for the EF1.

It's why I put the information from the EF1 in a previous post of mine in the event the OP wanted to try for himself.

[AnotherJohnson]

According to the Soundstage March, 2002 review http://www.soundstagenetwork.com/vinyl/vinyl200203.htm :

"The input load impedance is factory preset to 47k ohms, which is where I left it, but there are internal load selector switches that can be set for four other impedance values."

That having been said, switching them around may not make a hill of beans difference but they are there just as they are for the EF1.

It's why I put the information from the EF1 in a previous post of mine in the event the OP wanted to try for himself.

And we’re back to “I was disappointed that CJ didn’t include the manual for download.”

I thought maybe Roberto was on to something.

[Joe Appierto]

AJ, you answered his question in the very next post after his. Everything after that has been the bunch of us trying to be helpful.

[roberto]

Hola Chicos,

I did try to find the instructions manual and no luck. Our friend Joe has a good point regarding the switches.

The Dynavector 10X5 is a MC high output cartridge. I will try it with all the switches if off position. Definitively 49 dB gain is enough for any MM cartridge, and this Dynavector cartridge is about the same of a MM. I will try it and have a listen. Perhaps you might have to increase the position of the volume knob at your preamplifier, but this does not affect the quality of the sound.

Great advices here dear friends!

Happy listening!

[SteveFord]

I've got one of these arriving here next week.
Do you need a copy of the owner's manual for your database?

[AnotherJohnson]

I’m sure an EV-1 manual for the data base would be positive.
If not with the schematics, then perhaps here in this thread.
How big could it be? You could leave out the boiler plate and just scan the pages that pertain to unique aspects of its use.

[SteveFord]

This is exactly what the manual says:

Load Selectors: To select an input load impedance other than the
factory preset 47 kohms unplug the EV-1 and remove the cover. The
input impedance of the EV-1 is set by the load selector switches - the two
dual inline pin (dip) switch arrays located near the input connectors at
the back of the unit. Each dip array includes four switches labeled 1
through 4. Load impedances are selected as follows:
impedance switch #
1 2 3 4
47 kohms o o o o
9.6 kohms x o o o
1.9 kohms o x o o
500 ohms o o x o
200 ohms o o o x
x indicates switch in "on" position
o indicates switch in "off" position (indicated by arrow on switch)
Be sure to set both switches. Replace cover. Do not operate the unit
with the cover off.

Gain: 50 dB
Maximum Output: 20V
RIAA Equalization: within 25 dB
Hum and noise: 82 dB below 10 mV input
Phase: phase correct
Output impedeance: less than 800 ohms

Tube Compliment: 2 x 12AX7, 1 x 5751, 1 x 12AU7

Mechanical:
DImension: 13D x 19W x 3.315H inches
Net Weight: 12 lbs

Fuses
The EV1's power transformer is protected by a fuse on the ac power line. A failure of this fuse is a symptom of a more serious problem, and a competent service technician should be consulted. In no event should the fuse be replaced with a value or type different than that originally supplied. The fuses are located in a pull out compartment in the ac power line receptacle on the back of the chassis. The correct fuse values are:

If configured for 100 or 120V 1/2 amp, slow blow
If confisgured for 220 or 240V 1/4 amp slow blow