R93 with Tube Amp

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Victrolacollector
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R93 with Tube Amp

Post by Victrolacollector »

Has anyone used one of these lower priced tube amps with a phono like the R-93 phono attachment. I was wondering if it would give that same sound quality and tone as a good 1920’s RCA Victor RE-45 Electrola or Edison C-3?

https://rover.ebay.com/rover/0/0/0?mpre ... 2591831891

Damfino59
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Re: R93 with Tube Amp

Post by Damfino59 »

That kit is for a pre-amplifier for a magnetic cartridge. It is not a complete amplifier. You would still need a power amp to drive a speaker or speakers. I leave it for others more expieranced with horse shoe magnetic pickups on the proper impedence loading. I don’t have the background as my players of choice are purely mechanical. And my electrical players are post 1956!

Glenn

Vinrage_mania
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Re: R93 with Tube Amp

Post by Vinrage_mania »

that kit is equalized for RIAA curve ....78 records are not so it would not sound correct not bad per say you want a boost in gain but no eq ....then use an equalizer or tone controls to taste (before 1935 or so there were no set rules) for what an engineer might do while cutting a master

Phototone
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Re: R93 with Tube Amp

Post by Phototone »

The early horseshoe magnet pickups did not need a preamp, as they produced a signal strong enough to be fed directly into the driver stage of a power amp. The only "equalization" used was a capacitor low-pass filter comprised of a single capacitor to act as a scratch filter. A volume rheostat was normally installed between the pickup and the amplifier.

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ChuckA
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Re: R93 with Tube Amp

Post by ChuckA »

Phototone wrote:The early horseshoe magnet pickups did not need a preamp, as they produced a signal strong enough to be fed directly into the driver stage of a power amp. The only "equalization" used was a capacitor low-pass filter comprised of a single capacitor to act as a scratch filter. A volume rheostat was normally installed between the pickup and the amplifier.

Not really, there are two versions of horseshoe (magnetic) pickups. A high impedance version, these use a coil with DC resistance in the 500-1000 ohm range and with a good magnet and very compliant damper will generate up to about 1V p-p signal, which can drive a power amp to a decent volume. The low impedance versions have coils in the 10-100 ohm range and will only output 50mV-100mV p-p, way to low for a power amp. These were intended to be used with a step up input transformer that increases the signal to a little more than 1V p-p.

Most of those early amps didn't have any type of equalization, the majority may have had a capacitor and a variable resistor that acted as a shunt for high frequencies, AKA tone control. Victor had their "fuzz filter" which was a coil and capacitor network sometimes installed right after the pickup or in the plate circuit of the output tube to reduce the high frequencies. The Edison C-1 & C-2 had a network connected to the phono volume control to reduce the upper frequencies on needle cut records. Removing it improves the sound on DD's.



Chuck

PericeFinco
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Re: R93 with Tube Amp

Post by PericeFinco »

Hi...i am a new user here. As per my knowledge Tube amps of better quality would sound...better, but if it's not in the budget right now, why not enjoy what you just bought and experiment with more expensive alternatives later.
That said, you'd probably like a 300b amp if you have efficient speakers.

calculate percentages
Last edited by PericeFinco on Tue Sep 04, 2018 11:42 am, edited 1 time in total.

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marcapra
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Re: R93 with Tube Amp

Post by marcapra »

The Edison C-1 & C-2 had a network connected to the phono volume control to reduce the upper frequencies on needle cut records. Removing it improves the sound on DD's.
Chuck, I have one of your old Edison C-2s. I was thinking of doing just what you say here to improve the sound of my DDs. What do I have to do to remove that unit? Thanks, Marc.

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ChuckA
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Re: R93 with Tube Amp

Post by ChuckA »

marcapra wrote:
The Edison C-1 & C-2 had a network connected to the phono volume control to reduce the upper frequencies on needle cut records. Removing it improves the sound on DD's.
Chuck, I have one of your old Edison C-2s. I was thinking of doing just what you say here to improve the sound of my DDs. What do I have to do to remove that unit? Thanks, Marc.

Lift up the motor board, near the volume control is a small wood box with two wires connected to the control, just cut one of the wires.


Chuck

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