Vintage Amp Connection

[GuitarPicker]

How would I go about connecting an EICO ST-40 to a Marantz SR7013? A friend of mine rebuilds anything that has tubes and is letting me try this out .

 

[lovinthehd]

The amp manual is available at hifiengine.com....explanations of connections therein....

 

[GuitarPicker]

The amp manual is available at hifiengine.com....explanations of connections therein....

If I'm looking at this correctly I would go pre out front from SR7013 to MX inputs on the ST-40

 

[highfigh]

Find a way to use the Record Out jacks on the Marantz to send audio from all sources to one of the inputs of the Eico, whether Aux, Tape, Tuner, whatever. The line out needs to be fixed, not variable. It would be a good way to use Zone 2 or Zone 3, but set the level to Fixed and at about -10dB until you find out if that's too hot for the Eico.

I recently sold an ST-70- didn't have time to do anything with it.

 

[GuitarPicker]

Find a way to use the Record Out jacks on the Marantz to send audio from all sources to one of the inputs of the Eico, whether Aux, Tape, Tuner, whatever. The line out needs to be fixed, not variable. It would be a good way to use Zone 2 or Zone 3, but set the level to Fixed and at about -10dB until you find out if that's too hot for the Eico.

I recently sold an ST-70- didn't have time to do anything with it.

The Marantz SR7013 doesn't have record out jacks. The ST-40 does have tape out jack for recording. I'm currently running a 5.2.4 system and would like to use the ST-40 to power the front speakers. After giving it a spin last night by just connecting the front speakers directly to the amp I was blown away in the clarity and detailed separation in the right and left channel. The bass adjustment is really cool and I was blown away how good the lows sounded.

 

[PENG]

The Marantz SR7013 doesn't have record out jacks. The ST-40 does have tape out jack for recording. I'm currently running a 5.2.4 system and would like to use the ST-40 to power the front speakers. After giving it a spin last night by just connecting the front speakers directly to the amp I was blown away in the clarity and detailed separation in the right and left channel. The bass adjustment is really cool and I was blown away how good the lows sounded.

You can try connected the Marantz pre out to the tape 1 input of the ST-40 but be very careful as you may over drive the ST-40. As extra precaution, I suggest you set the trim level of the channel you are going to use to the minimum, that would be -12 dB if I remember right.

 

[highfigh]

The Marantz SR7013 doesn't have record out jacks. The ST-40 does have tape out jack for recording. I'm currently running a 5.2.4 system and would like to use the ST-40 to power the front speakers. After giving it a spin last night by just connecting the front speakers directly to the amp I was blown away in the clarity and detailed separation in the right and left channel. The bass adjustment is really cool and I was blown away how good the lows sounded.

You don't need to use the Rec Out jacks on the EIco and the Marantz doesn't have analog Rec Out, but you can use the Zone 2 or Zone 3 output and set it to 'Fixed', as I had posted.

 

[GuitarPicker]

I'm wanting to use my main front speakers in my current setup for music listening through the Eico ST-40. Is there an easy way to do this? In Zone 2 I would need a separate pair of speakers?

 

[Eppie]

I'm wanting to use my main front speakers in my current setup for music listening through the Eico ST-40. Is there an easy way to do this? In Zone 2 I would need a separate pair of speakers?

@highfigh was correct above. If the Eico has its own volume and tone section, then you want a fixed line-level output running from the Marantz to the Eico. The Marantz SR7013 has a section on the back labeled "Pre Out" which is normally controlled by the Marantz volume level. You can use the Zone2 or Zone3 from Pre Out but then go into the Marantz settings and set either Zone2 or Zone3 to fixed to get a fixed line-level signal. Use the Tape or Aux input on the Eico.

If you are only using 2 speakers, then just run everything through the Eico. If you have multiple speakers in a surround setup for movies, then things get more complicated. You will either need another pair of speakers dedicated to the Eico, or a good quality speaker switch to switch the two main speakers from the Marantz to the Eico for music. Don't cheap out on the switch. It has to be a 'break before make' switch designed to be used with two amplifiers to avoid damaging your equipment.

Note that you should avoid having the Eico powered on without any speakers connected. Tube amps do not like to be run without a load present.

 

[GuitarPicker]

@highfigh was correct above. If the Eico has its own volume and tone section, then you want a fixed line-level output running from the Marantz to the Eico. The Marantz SR7013 has a section on the back labeled "Pre Out" which is normally controlled by the Marantz volume level. You can use the Zone2 or Zone3 from Pre Out but then go into the Marantz settings and set either Zone2 or Zone3 to fixed to get a fixed line-level signal. Use the Tape or Aux input on the Eico.

If you are only using 2 speakers, then just run everything through the Eico. If you have multiple speakers in a surround setup for movies, then things get more complicated. You will either need another pair of speakers dedicated to the Eico, or a good quality speaker switch to switch the two main speakers from the Marantz to the Eico for music. Don't cheap out on the switch. It has to be a 'break before make' switch designed to be used with two amplifiers to avoid damaging your equipment.

Note that you should avoid have the Eico powered on without any speakers connected. Tube amps do not like to be run without a load present.

I'm running a 5.2.4 system. I'm thinking my only other option is to have 2 sets of speaker wires and swap back and forth. I may try connecting like hifigh and Peng suggested but I'm concerned that the 20w per channel may not keep up with the entire system when listening to movies? If you have a switch you recommend I would be interested in looking at that option.

 

[lovinthehd]

You could still use the pre-outs and have the option of finding an appropriate volume setting on the Eico to work with the Marantz, might take some fussing to find the best combination, tho. I'd assume you're limited to the Eico's lower power/volume when using it with the Marantz amp section....

 

[Eppie]

20W vs the 110W of the Marantz is a big differential. I read that Niles makes some decent switches. Problem is that it's hard to find proper connectors. The Niles DPS-1 is designed for 2 amps and one set of speakers, but it uses screw down terminals. It's rated at 300W so it can handle the power.

Something like this on Amazon is cheaper and uses standard terminals but is only rated at 100W RMS.

 

[TLS Guy]

I'm running a 5.2.4 system. I'm thinking my only other option is to have 2 sets of speaker wires and swap back and forth. I may try connecting like hifigh and Peng suggested but I'm concerned that the 20w per channel may not keep up with the entire system when listening to movies? If you have a switch you recommend I would be interested in looking at that option.

If you are running a multichannel AV system, it makes absolutely no sense to put and integrated tube amp in the mix. I tell you what it will do. You will end up shorting wires and blow the Marantz up. Or you will leave the speaker output of the EICO not connected. That blows up the output tubes really fast. And I mean they can literally blow up with a violent explosion.

If you want to use that amp, then put together a vintage set up of the period and use it in a stand alone system, where you are not futzing and preparing to destroy good equipment. I can assure that will be the outcome of your plan.

An integrated tube amp, or any integrated amp for that matter, does not belong in any multichannel AV system.

The bottom line is stop courting disaster and ruining good equipment.

 

[highfigh]

@highfigh was correct above. If the Eico has its own volume and tone section, then you want a fixed line-level output running from the Marantz to the Eico. The Marantz SR7013 has a section on the back labeled "Pre Out" which is normally controlled by the Marantz volume level. You can use the Zone2 or Zone3 from Pre Out but then go into the Marantz settings and set either Zone2 or Zone3 to fixed to get a fixed line-level signal. Use the Tape or Aux input on the Eico.

If you are only using 2 speakers, then just run everything through the Eico. If you have multiple speakers in a surround setup for movies, then things get more complicated. You will either need another pair of speakers dedicated to the Eico, or a good quality speaker switch to switch the two main speakers from the Marantz to the Eico for music. Don't cheap out on the switch. It has to be a 'break before make' switch designed to be used with two amplifiers to avoid damaging your equipment.

Note that you should avoid have the Eico powered on without any speakers connected. Tube amps do not like to be run without a load present.

And they REALLY don't like the load to be applied or removed while powered, although there's a YouTube video of David Gilmore doing exactly that to a Tweed Fender Deluxe amp, which is a classic model. Its jack may have been a bit oxidized when he turned it on and it didn't produce any sound, so he picked it up, unplugged it and reinserted the plug.

As much as this advice has been passed around, tube amps are amazing resilient- I have a 1958 Fender Bassman and one night, as a friend was using it during a gig, I saw a bright flash on the wall behind it just before it stopped making sound. It had blown the fuse and when I put another in, that went immediately. Turned out to be a carbon trace on an output tube socket. After the sockets were replaced, it has been working fine ever since and that happened in the late-'80s.

 

[highfigh]

If you are running a multichannel AV system, it makes absolutely no sense to put and integrated tube amp in the mix. I tell you what it will do. You will end up shorting wires and blow the Marantz up. Or you will leave the speaker output of the EICO not connected. That blows up the output tubes really fast. And I mean they can literally blow up with a violent explosion.

If you want to use that amp, then put together a vintage set up of the period and use it in a stand alone system, where you are not futzing and preparing to destroy good equipment. I can assure that will be the outcome of your plan.

An integrated tube amp, or any integrated amp for that matter, does not belong in any multichannel AV system.

The bottom line is stop courting disaster and ruining good equipment.

If the Marantz is connected via a Rec Out (if it had one) or one of the Zone outputs set for fixed output, there's little chance for it to be damaged unless there's a problem in the Eico and if the coax audio cable shorts to ground, it won't hurt anything. There's no issue with the input or output impedance, although a reversed power plug on the EICO could cause trouble- a grounded power cord should be installed, but only after determining correct polarity for the EICO's power transformer.

I can't agree more about the need for a constant acceptable load on the output of the EICO, though.

 

[highfigh]

20W vs the 110W of the Marantz is a big differential. I read that Niles makes some decent switches. Problem is that it's hard to find proper connectors. The Niles DPS-1 is designed for 2 amps and one set of speakers, but it uses screw down terminals. It's rated at 300W so it can handle the power.

Something like this on Amazon is cheaper and uses standard terminals but is only rated at 100W RMS.

Not with a tube amp. If the load on a tube amp is more than one step from what the output transformer tap is supposed to see, it stresses the output tubes and can damage them. That can cause other damage, like the problem I described in my amp and if it takes out the output transformer, it's not a good thing but that often blows the fuse before it kills the whole thing.

 

[Eppie]

Not with a tube amp. If the load on a tube amp is more than one step from what the output transformer tap is supposed to see, it stresses the output tubes and can damage them. That can cause other damage, like the problem I described in my amp and if it takes out the output transformer, it's not a good thing but that often blows the fuse before it kills the whole thing.

I suppose I failed to mention that both amps must be turned off when switching amps, especially with a tube amp, but I have to agree with TLS Guy. The Marantz and Eico are such different pieces of equipment that it makes more sense to set up a dedicated vintage system. He could always try the Eico with his mains first to see if he likes the amp and then invest in speakers later.

 

[lovinthehd]

Personally I can't imagine wanting the tube amp mixed into the system at all....reminds me why I don't want to fuss with tubes.

 

[GuitarPicker]

Personally I can't imagine wanting the tube amp mixed into the system at all....reminds me why I don't want to fuss with tubes.

I never shopped for one. I had the opportunity to take this home to try and I was hooked. Actually he asked me a couple times to come get it. The real test is when I connect it to main fronts. I may end up using this as a stand alone system just for music or get a speaker switch box. Not only is it nostalgic and sounds great it's a fun project and something new. I own 2 tube guitar amps and to me they sound better than any solid state amps I've ever tried. The cool thing about tubes is you can have them repaired. Nobody wants to fool with the solid state stuff and it's almost disposable. I mean how cool is it to play music thru something that was made in 1960? Not to mention that he is selling it to me for just what he has in it. If anything it will be a good investment.

 

[lovinthehd]

Enjoy, just not my cup of tea. I can see extended use of gear, just have no desire for tubes. For guitar playing maybe, for audio reproduction just doesn't appeal and my solid state stuff is getting pretty old fwiw. Things get old, heck I was made before 1960....