Do I have to worry about impedance when connecting preamp to amp in a non-standard way

[Echolane]

I want to add more source input capability to a Pioneer SX-1050. The 1050 does all the audio in my TV stereo system. I do have an AVR, but I much prefer the audio of the Pioneer so my AVR is limited to doing video switching. The Pioneer has four inputs and I need six. One way to add additional source inputs is to put a Musical Fidelity A3cr Preamp to use that I’ve had in storage. The suggestion was to connect Tape Out on the Musical Fidelity to Aux on the Pioneer. But I was warned that the impedance must be compatible.

Unfortunately, I know zip about impedance and less about how to check it. So Im hoping someone who reads this will know more about it than I do and tell me what I need to do. Or maybe I don’t even need to worry about it.

 

[slipperybidness]

The simple solution is the best solution.

All I'm seeing in your current setup and your planned setup is unnecessary complexity.

 

[Echolane]

2

The simple solution is the best solution.

All I'm seeing in your current setup and your planned setup is unnecessary complexity.

does that mean you have a better idea? I would love to have a better idea!

 

[PENG]

I want to add more source input capability to a Pioneer SX-1050. The 1050 does all the audio in my TV stereo system. I do have an AVR, but I much prefer the audio of the Pioneer so my AVR is limited to doing video switching. The Pioneer has four inputs and I need six. One way to add additional source inputs is to put a Musical Fidelity A3cr Preamp to use that I’ve had in storage. The suggestion was to connect Tape Out on the Musical Fidelity to Aux on the Pioneer. But I was warned that the impedance must be compatible.

Unfortunately, I know zip about impedance and less about how to check it. So Im hoping someone who reads this will know more about it than I do and tell me what I need to do. Or maybe I don’t even need to worry about it.

I don't know what kind of AVR you have now but I can tell you based on specs, any of the recent mid range AVRs from Yamaha, Denon, Marantz, and Pioneer should have no trouble beating the 40 years old SX-1050 even if it is in top condition. You probably read a lot about vintage electronics "sound better" than today's, but while that could be true in some or even many cases, more often than not its just myth, hearsay etc.

The fact is, technology does not remain static, it advances, so just because newer gear tend to be lighter and cheaper, it does not mean they don't do a better job than those 30-40 years old gear, all else (power out rating, noise specs etc..) being equal.

SX-1050 audio specs:
THD (20-20,000 Hz from AUX)
Cont. rated output..............<0.1%
60 WPC, 8 ohms.................<0.05%
IMO (50Hz:7000Hz 4:1, from Aux).......<0.06%
Input sensitivity/Impedance................ 1V/50 k ohms

If you really want to do it your way, yes the Musical Fidelity Preamp's can work with the SX-1050. I could not find any output impedance spec for your MF preamp, but the Pioneer's input impedance being 50 k ohms, that should be high enough for just about any well designed preamp such as MF's.

 

[highfigh]

I want to add more source input capability to a Pioneer SX-1050. The 1050 does all the audio in my TV stereo system. I do have an AVR, but I much prefer the audio of the Pioneer so my AVR is limited to doing video switching. The Pioneer has four inputs and I need six. One way to add additional source inputs is to put a Musical Fidelity A3cr Preamp to use that I’ve had in storage. The suggestion was to connect Tape Out on the Musical Fidelity to Aux on the Pioneer. But I was warned that the impedance must be compatible.

Unfortunately, I know zip about impedance and less about how to check it. So Im hoping someone who reads this will know more about it than I do and tell me what I need to do. Or maybe I don’t even need to worry about it.

You need an outboard source switcher.

 

[PENG]

The suggestion was to connect Tape Out on the Musical Fidelity to Aux on the Pioneer. But I was warned that the impedance must be compatible.

You should use the preamp output of the MF preamp, pull the bridging plugs of the SX-1050 out so as to use it as a power amp. Isn't that's what you want to do? If you want to use the inputs of both the MF preamp and the SX-1050, then you are going to have to add some sort of source switcher that highfigh mentioned in post#5.

Tape out may work but I wouldn't recommend it without seeing the specifications first. No harm trying though, especially if you believe in going by ears is the best way.

 

[Echolane]

I don't know what kind of AVR you have now but I can tell you based on specs, any of the recent mid range AVRs from Yamaha, Denon, Marantz, and Pioneer should have no trouble beating the 40 years old SX-1050 even if it is in top condition. You probably read a lot about vintage electronics "sound better" than today's, but while that could be true in some or even many cases, more often than not its just myth, hearsay etc.

The fact is, technology does not remain static, it advances, so just because newer gear tend to be lighter and cheaper, it does not mean they don't do a better job than those 30-40 years old gear, all else (power out rating, noise specs etc..) being equal.

SX-1050 audio specs:
THD (20-20,000 Hz from AUX)
Cont. rated output..............<0.1%
60 WPC, 8 ohms.................<0.05%
IMO (50Hz:7000Hz 4:1, from Aux).......<0.06%
Input sensitivity/Impedance................ 1V/50 k ohms

If you really want to do it your way, yes the Musical Fidelity Preamp's can work with the SX-1050. I could not find any output impedance spec for your MF preamp, but the Pioneer's input impedance being 50 k ohms, that should be high enough for just about any well designed preamp such as MF's.

My AVR is an Arcam SR-250, an unusual two-channel AVR. I’m a two channel ”audiophile” dinosaur with zero interest in a multi channel system so the Arcam suits me very well. The Arcam has an MSRP of ~$3500 so it’s no dog. In fact I chose it because it was heavily advertised for its superior audio. I did not think that was true AT ALL so I hauled my SX-1050 out of the closet where it had been for over 30 years and it was transformative. All of a sudden I could understand dialogues a lot better. Musically there was no comparison, the 1050 was far more musical. I had it refurbished at that point. It’s even better now. The 1050 is exceptionally musical. I’m an opera lover and listen to a lot of musical programming. The Arcam sounds “muddy” and dull in comparison.

THANK YOU much for the impedance info. That is very helpful.

 

[Echolane]

You should use the preamp output of the MF preamp, pull the bridging plugs of the SX-1050 out so as to use it as a power amp. Isn't that's what you want to do? If you want to use the inputs of both the MF preamp and the SX-1050, then you are going to have to add some sort of source switcher that highfigh mentioned in post#5.

Tape out may work but I wouldn't recommend it without seeing the specifications first. No harm trying though, especially if you believe in going by ears is the best way.

I actually paired the Musical Fidelity and the Pioneer in the way you suggest, pulling the bridging plugs, and I could do that again, but the audio of preamps is dominant and I want the Pioneer’s audio qualities to be dominant. The Musical Fidelity is exceptionally well regarded in the reviews, but my impression is that the Pioneer is better.

 

[PENG]

I actually paired the Musical Fidelity and the Pioneer in the way you suggest, pulling the bridging plugs, and I could do that again, but the audio of preamps is dominant and I want the Pioneer’s audio qualities to be dominant. The Musical Fidelity is exceptionally well regarded in the reviews, but my impression is that the Pioneer is better.

Going by specs the MF is better but again if you trust your ears you can try using the tape out so that you will be using the Pioneer's volume control. If it sound better to you and you are getting enough output at the same volume position (the Pioneer's) then you are all set.

 

[Echolane]

You need an outboard source switcher.

Please tell me where I can find an outboard source switcher that gets good reviews. I need capacity for six sources, but will settle for five.

Actually, that is where I started. Most of them are very inexpensive which is certainly appealing, but Amazon reviews had a high percentage of negatives and they weren’t encouraging to read. The impression I got was they were Chinese junk and if you got lucky they would work for awhile at least. So being an overly analytical sort I got scared away And started looking for alternatives. Which brought me to using the MF as described.

I should add that I think a very high quality AV switch would make a great replacement for my AV receiver and would suit my needs very well because I would not need to invest in an audio video receiver, whose main purpose seems to be video switching and multi-channel ”processed” music. I guess I’m old fashioned but I’m not into “processed” audio and am perfectly content with high quality two-channel audio.

 

[PENG]

Please tell me where I can find an outboard source switcher that gets good reviews. I need capacity for six sources, but will settle for five.

If you pioneer has 4 already, and you need a total of six, then you only need a 3 in 1 out switch to have a total of 6, or a 4 in 1 out to have a spare.

Amazon.com: RCA Switch Stereo 4 in 1 Out Audio Signal Source Switcher HiFi Input Selector Splitter Box: Home Audio & Theater

The linked one is pricy but there are cheaper ones for sure if you do a search.

In my opinion, such a passive device is very simple and as long as good quality parts are used they should be as good if not better than the build in switching devices in the Pioneer. If you are concern about potential signal degradation, then buy it from Amazon and pick a vendor that have a good return policy.

 

[highfigh]

Please tell me where I can find an outboard source switcher that gets good reviews. I need capacity for six sources, but will settle for five.

Actually, that is where I started. Most of them are very inexpensive which is certainly appealing, but Amazon reviews had a high percentage of negatives and they weren’t encouraging to read. The impression I got was they were Chinese junk and if you got lucky they would work for awhile at least. So being an overly analytical sort I got scared away And started looking for alternatives. Which brought me to using the MF as described.

I should add that I think a very high quality AV switch would make a great replacement for my AV receiver and would suit my needs very well because I would not need to invest in an audio video receiver, whose main purpose seems to be video switching and multi-channel ”processed” music. I guess I’m old fashioned but I’m not into “processed” audio and am perfectly content with high quality two-channel audio.

You're worried about reviews, I offered a solution for adding inputs to a 45 year old receiver. Think about it- you need inputs and millions of used receivers, preamps and integrated amps are out there that will be at least as good as your Pioneer- buy one and only use it for the inputs so you can send the output to one of the inputs of the SX-1050. If you buy a preamp, look for one that doesn't take much space, like an Adcom, NAD, etc. If you want a very small one, look at the Parasound ZPre.

 

[slipperybidness]

2

does that mean you have a better idea? I would love to have a better idea!

The better idea is to ditch the vintage gear, or make it a dedicated system, and use a dedicated AVR (which you already have, but don't seem to like)

I am skeptical that the vintage Pio really sounds that much better on an objective basis vs. the Arcam.

 

[Echolane]

The better idea is to ditch the vintage gear, or make it a dedicated system, and use a dedicated AVR (which you already have, but don't seem to like)

I am skeptical that the vintage Pio really sounds that much better on an objective basis vs. the Arcam.

I wish you could hear the difference in audio quality for yourself. I often find it difficult to tell the difference in a/b testing of cables, for example, but in this case it was simple and instantly obvious. The Arcam sounds dull and muddy in comparison to the Pioneer. Dialog is much easier to understand. I What’s more, I’m not alone in finding that a good stereo receiver sounds better than an AVR. Many reviewers will mention this.
I had an opportunity just this month to ask the opinion of a PhD engineer who works independently in audio and I asked him if I made the right decision to refurbish my SX-1050 and he responded in the affirmative. He also lamented the fact that he hadn’t kept his Marantz of a similar era! Others have told me that that the capacitors and other parts used at that time were more musical than is typical of those of today and if the parts in my Pioneer are still in spec to keep them rather than replace them. Still others comment that products of that era were made to last so that refurbished and with proper care my Pioneer can last another 50 years. Which means it will outlive me considerably but I will enjoy it as long as I’m on the planet.

Besides that what does an AVR offer me that I’m interested in? Very little. I very much appreciate its many HDMI ports, though I lament the loss of component and/or S-Video ports For my laser disc player and my VHS/DVD player. I love the ability to control source selection and volume with a remote. I can think of nothing else that I use. my Arcam is a two-channel AVR which I chose deliberately because I have no need of the extra amplifiers which surely add considerably to the cost. I don’t need room correction. The money devoted to engineering and manufacturing those features which are on almost all AVRs are wasted on me. Then there’s all the audio processing which I deliberately bypass so I can use analog circuitry as much as possible. I would be happy with a *quality* product that was basically an AV switch with remote control that was cheap enough that it could be easily upgraded or replaced as new TV technology comes along that would obsolete it.

 

[Echolane]

You're worried about reviews, I offered a solution for adding inputs to a 45 year old receiver. Think about it- you need inputs and millions of used receivers, preamps and integrated amps are out there that will be at least as good as your Pioneer- buy one and only use it for the inputs so you can send the output to one of the inputs of the SX-1050. If you buy a preamp, look for one that doesn't take much space, like an Adcom, NAD, etc. If you want a very small one, look at the Parasound ZPre.

I like your advice, especially since it seems I am already prepared to do just as you suggest.. Except I don’t think I need to buy anything as I already have quite a nice “switcher” in my Musical Fidelity A3cr Preamp. It’s only apparent downside is it’s size. It is built like a tank and weighs almost 30 pounds and I will indeed have to struggle a little to accommodate it. And based on comments in this thread my concerns about impedance compatibility seem unfounded. I just need to give it a good listening test to be sure.

 

[lovinthehd]

All this concern over electronics seems a bit odd, what speakers are you using?

 

[Echolane]

All this concern over electronics seems a bit odd, what speakers are you using?

Not sure my speakers are pertinent, but they are Spendor FL-6 floor standing speakers. And recently had the surrounds refoamed.

 

[lovinthehd]

Not sure my speakers are pertinent, but they are Spendor FL-6 floor standing speakers.

Because most sound quality is derived from your speaker/room interface, not the electronics. Can't imagine the electeronics being that big a difference unless something is broken, and I certainly don't miss my old 2ch receivers from that period. That you "listen" to cables isn't a good sign, let alone reliance on subjective reviews. Good luck, tho.

 

[Echolane]

Because most sound quality is derived from your speaker/room interface, not the electronics. Can't imagine the electeronics being that big a difference unless something is broken, and I certainly don't miss my old 2ch receivers from that period. That you "listen" to cables isn't a good sign, let alone reliance on subjective reviews. Good luck, tho.

Actually I’ve given up dealing with the subjective opinions on interconnect cables, speaker wire, fuses, AC power outlets and so on.

 

[lovinthehd]

Actually I’ve given up dealing with the subjective opinions on interconnect cables, speaker wire, fuses, AC power outlets and so on.

Why did you give it credence in the first place?